NORTH AMERICAN COLEOPTERA. 49 in Dr. LeConte's collection is to be relied on, and differs from it supeificiuUy in the nature of the elytral sculpture, as well as in the relatively more elongated prothorax. I have not had an op[)ortunity to examine it more minutely. If the two should prove identical, it will be a source of surprise that Haldeman's species should have been suppressed and united with extricata. The above differences are so marked that it is difficult to conceive of their having been overlooked.
PLATYDEMA.
P. pernigrillll n. sp. — Form regularly elliptical, elongated, moderately convex, more than twice as long as wide ; glabrous, opaque. Color above deep black, beneath rufous. Head wider than long, somewhat trapezoidal ; anterior margin transverse, angles rounded ; interocular surface nearly flat, punctures throughout very small, round, deeply impressed, very closely crowded, evenly distributed ; antennae slightly shorter than the basal width of pronotum, first four joints reddish-testaceous, joints five to ten black, last joint reddish-testaceous, the outer joints distinctly flattened, joints eight to ten distinctly broader than long ; last joint of the maxillary j^alpi twice as long as wide, as long as the second and third together ; mentura slightly longer than wide, narrowed toward the base, anterior angles broadly rounded, feebly emarginate anteriorly, exposed surface very strongly convex in the midd-^e, the summit of the nearly hemispherical convexity bearing a transverse,bilobed, spongy patch ; mandibles very strongly bidentate at tip, teeth very acute. Prothorax at base twice as wide as long; base one-half longer than the apex, transverse and straight at the sides, strongly arcuate in its middle third ; apex broadly and feebly emarginate ; sides evenly and feebly arcuate ; anterior and posterior angles slightly rounded ; disk broadly and evenly convex, narrowly reflexed at the sides, which are narrowly margined, lateral edges acute ; surface most minutely granulate, also evenly and very finely punctulate, punctures very feeble. Scutellum slightly wider than long, acute posteriorly, sides arcuate. Elytra at base as wide as the contiguous pronotum ; sides parallel and moderately arcuate for two-thirds tlieir length from the humeri ; disk three times as long as the pronotum, rather acutely and very evenly rounded behind ; sides narrowly and rather strongly reflexed throughout ; surface punctate, punctures round, rather deep, sub-variolate, arranged in rather distant striae, distance of punctures in the rows equal to about one-third the distance between the latter ; also very finely, evenly, closely, and feebly punctulate ; finally excessively finely granulate. Posterior portion of fourth, and anterior portion of the fifth ventral segments having a deep, transverse, and common impressed groove. Legs moderate ; first joint of the posterior tarsi equal to two-fifths the entire length of the latter. Length 6.7 mm. ; width 3.2 mm.
Arizona (Morrison).
This*species differs from P. Janus in its much more elongate form; in the color, that oi' jcmtis being usually of a reddish-black above; in Published August, 1884. 4
50 TIIOS. L. CASEY.
the shape of the nientum, that o^ Janus heing broader than long; in the punctuation of the head, that of pernigrum being much more dense ; also in the length of the eye. The antennae and sculpture are almost exactly the same in both. The three specimens of the present species before me do not perceptibly vary.
P. parvuluill n.sp. — Form rather elongated, elliptical, twice as long as wide ; upper surface polished, dark piceous, niider surface slightly paler. Head small ; iuterocular surface strougly declivous, rather feebly tuberculate near each eye ; epistoma nearly plane, scarcely declivous, with a very broad, feeble, transverse furrow separating it from the declivous portion, very broadly and feebly swollen in the middle ; anterior margin very broadly rounded, nearly transverse in the middle ; labrum very broadly rounded, short, punctures between the eyes small, round, feebly impressed, evenly distributed, and separated by nearly twice their own widths ; those of epistoma much more distant ; surfaces minutely granulate, shining ; antennae robust, short, scarcely as long as the width of pronotum, piceous-brown throughout, second joint two-thirds as long as the third, third and fourth equal in length, penultimate joints very strongly transverse. Prothorax at base slightly more than twice as wide as long ; base one-half wider than the apex; side feebly and very evenly arcuate; anterior and posterior angles rounded ; anterior margin broadly and evenly emargiuate, posterior feebly bisiuuate, strongly arcuate in the middle ; disk with two feeble impressions at the base, moderately convex, minutely, rather evenly and distantly punctate, also minutely reticulated, polished. Scutellum slightly longer than wide. Elytra at base slightly wider than the contiguous pronotum; sides parallel and rather strongly arcuate for two-thirds the length from the humeri ; disk evenly convex, slightly more than three times as long as the pronotum, rather acutely rounded behind, feebly striate ; striae impressed and very strongly punctate, distance between punctures in striae, slightly more than one-third the distance between the latter ; intervals very feebly convex, very minutely, evenly, rather distantly and distinctly punctulate, also minutely reticulated, polished. Under surface of the abdomen sparsely and rather feebly punctate, more finely and distantly so on the last segment. Fourth joint of posterior tarsi equal in lengtli to the second and third together, much shorter than the first. Length 3.1 mm.
"Wilk'ts Point, Long Island ; one specimen, % .
This tine little species resembles somewhat a very minute excavation, in which the frontal horns are rudimentary. It is seen, however, to be very distinct by the short antennae, having very strongly transverse outer joints, and by the punctuation of the pronotum. In e.rcavatum the penultimate joints are very feebly transverse, and the second joint is relatively very much shorter ; the punctuation of the pronotum is much coarser, and the basal impressions are not as strong; the color, also, is deep black. The prosternal episterna are much more feebly and sparsely punctured in parcnlam.
NORTH AMERICAX COLEOPTKRA. 51 It also resembles miccins Horn, but in that species, which is more southern in its habitat, the head is not bituberculate, and the penultimate antennal joints seem to be still more transverse.
P. opacilllIIU n. sp. — Form elliptical, nearly twice as long as wide, very moderately convex ; surface above opaque, deep black, beneath dark blackish-fuscous ; antennae and legs dark fuscous. Head moderate, slightly wider than long; surface nearly plane, coarsely and closely punctate, more finely and distinctly so anteriorly ; anterior margin broadly rounded ; labrum very short and broad ; antennae uniform in color, as long as the width of prothorax, robust, slightly flattened toward the tip, second joint less than one-half as long as the third, joints three, four, and five decreasing uniformly and very gradually in length ; mentum slightly broader than long, broader at apex than at base, sides nearly straight, anterior angles slightly rounded, anterior margin broadly and feebly emarginate, exposed surface feebly convex and having numerous long, blackish, erect setae ; maxillary palpi well developed, last joint very robust, slightly shorter than the two preceding joints together, nearly as wide as long, broadly and obliquely truncate at tip, where it is deeply hollowed. Prothorax much more than twice as wide as long ; base nearly one-half longer than the apex ; sides moderately and very evenly arcuate ; anterior and posterior angles slightly rounded, the former obtuse, the latter acute ; apex bisinuate and transverse, base bisiuuate and strongly arcuate in the middle ; disk rather feebly, closely, and evenly punctate ; minutely granulate. Scutellum slightly wider than long, apex acute, sides feebly arcuate. Elytra at base as wide as the jironotum ; sides parallel and moderately arcuate for three-fourths the length from the humeri ; disk evenly convex, more than three times as long as the pronotum, one-half longer than wide, broadly and evenly rounded behind, strongly punctate; punctures round, deeply impressed, arranged in striae-like rows ; distance between punctures in the rows, scarcely one-third of that between the latter; intervals flat, very obscurely, excessively faintly, and rather distantly punctulate, also minutely granulate ; near the scutellum and the suture there is a very short row of punctures on each elytron. Under surface of abdomen very coarsely and evenly punctate ; punctures of last segment much finer. First joint of the posterior tarsi slightly longer than the next two togethei". Length 3.9 mm.
Pennsylvania, near Philadelphia ; one specimen.
P. rvjicorne, the only species with which the present one can be compared, is much longer and paler beneath, where it is much more finely punctate; the punctures of the elytral series are much finer, and their distance asunder in the rows is generally tour or five times less than the distance between the latter.
DISOIVYCHA.
I>. pulclira n. sp. — Form rather elongated, elliptical, moderately convex; glabrous ; shining. Head broader than long, surface moderately convex,
02 THOS. L. CASEY.
irapuiictate ; labrum three times as broad as long, rather feebly emarginate anteriorly ; eyes large, rather prominent, much shorter than wide, emarginate anteriorly ; antennae two-thirds as long as the elytra, robust, nearly black, basal joint slightly paler, very finely pubescent, basal joint as long as the next two together, joints four to ten nearly equal in length, obliquely truncate at their distal extremities, terminal process of last joint acuminate and large ; last joints of labial and maxillary palpi subulate and partly enveloped by the penultimate ; mentum slightly broader than long, somewhat trapezoidal, surface broadly, feebly, and very evenly convex, edges rounded. Prothorax two and one-third times wider than long ; base transverse and nearly straight in the middle half, thence bent slightly anteriorly and straight to the basal angles, which are rounded slightly and very obtuse ; apex broadly and evenly arcuate throughout ; anterior angles broadly rounded ; sides strongly arcuate posteriorly, nearly straight or slightly sinuate near the apical angles ; disk impunctate, except under a very high power, when it is seen to be most finely, distantly, and just visibly punctulate, and most excessively finely reticulated ; sides flat and porrected ; near each basal and apical angle there is a long seta. Scutellum slightly broader than long, triangular. Elytra at base as wide as the contiguouspronotum;sidesparallelandratherstronglyarcuateforfour-fifths the entire length ; disk four times as long as the pronotum, obtusely rounded behind, minutely granulated, very feebly, distantly, and evenly punctulate ; each elytron having a narrow black vitta along the suture, a medial one nearly twice as wide, which does not attain the elytral tip, and a narrow marginal vitta, just inside the narrow porrected border ; the latter and the reuiaindi^r of the disk red, the margins of the red vittae being paler. Under surface bright rufo-testaceous. Legs moderate, rufous, except the tips of the tibiae and the tarsi, which are piceous-black ; terminal spur of the posterior tibiae acute, stout and slightly bent. Length 6.5 mm.
Near Chester, Pennsylvania ; two specimens.
The general color of the head and prothorax is red ; the pronotum has two black points in the middle anteriorly; exterior to these spots the surface becomes paler, nearly wliite, beyond much deeper red, and at the lateral nuirgins again i)aler. The integument of the pronotum is so thin and transparent that tlie bloodvessels and general circulatory system can be perfectly seen tlirough it; it is to these vessels that the color of the paler patches is due. Tlie s|)ecimens were found under debris on the shores of the Delaware Kiver. ]>. ai'izoiiae n. sp. — Form elongated, moderately convex, increasing in width jiostcriorly. Upper surface glabrous, polished; yellow, vittae and spots black ; under surface very sparingly pubescent, piceous-brown. Head rather small, as long as wide ; surface pale piceous-brown, more or less mottled, feebly convex, having numerous scattered setigerous punctures near the eyes, the latter very convex, short, and prominent, emarginate anteriorly ; between the bases of the antennae there is a deep transverse furrow, acutely augulate posteriorly, which is the posterior limit of a convex,
NORTH AMERICAN COLEOPTERA. 53 longitudinal, inter-antennal elevation ; labrum four times as wide as long, broadly emarginate anteriorly ; antennae about one-half as long as the elytra, piceous-black, base infuscate, second joint nearly globular, joints four to ten decreasing rapidly in length, the former twice as long as wide, the latter quadrate ; finely pubescent toward the tip ; mentum longer than wide, sides nearly parallel, transversely truncate anteriorly, surface convex. Prothorax nearly two and one-half times as wide as long ; base broadly arcuate, feebly sinuate in the middle and near the basal angles, apex nearly transverse ; apical angles prominent, rounded, and callous, posterior very slightly rounded ; sides moderately divergent posteriorly, arcuate, very feebly sinuate near the apical callosities ; disk more or less broadly, feebly, and irregularly impressed, minutely and distinctly rugulose, very minutely and distinctly reticulated, rather sparsely and finely punctured ; margins narrowly reflexed. Scutellum wider than long, triangular. Elytra across the humeral protuberances distinctly wider than the pronotum ; sides divergent and nearly straight for two-thirds the length ; disk broadly and obtusely rounded behind, nearly five times as long as the pronotum, highly polished, extremely feebly reticulated, finely and evenly punctulate, each elytron having a very narrow black vitta along the interior edge attaining the tips, a broader median vitta not attaining the tip, and a narrow marginal vitta attaining the tip, remainder of the disk tlavate. Under surface of the abdomenmottled very confusedly with rufous, dark piceous-brown, and ochreousyellow ; legs piceous-brown throughout, femora confusedly clouded. Length (3.5 mm.
Arizona (Morrison).
The differences between tlie present species and pnlchra are almost generic, and lie principally in the structure of the palpi, mentum, and prosternal intercoxal process. The latter in arizontB is dilated posteriorly and transversely truncate behind ; in pnlchra it is narrower and gradually nan-owed posteriorly to the tip, which is acute ; in pennsylvanica it is narrow, with the sides nearly parallel, and the surface is very densely hirsute ; these differences may serve as a convenient basis of classification. The only ornamentation of the pronotum in arizonce consists of two small bhick spots rather distant and just in advance of the middle.
CH^TOCIVEMA.
C> paiipercilla n. sp. — Form rather slender; glabrous. Color above bronzed, beneath pale piceous-brown ; shining. Head nearly twice as wide as long ; interocular surface evenly and rather feebly convex, finely, deeply, and very distinctly granulate, also minutely, rather sparsely and distinctly jiunctulate ; labrum nearly three times as wide as long, transverse anteriorly; eyes broadly emarginate anteriorly, the upper margin of the eyes, which are nearly straight, are produced anteriorly as two deep straight convergent grooves, which connect with a very short transverse groove between the bases of the antennae ; this transverse line is broadly 4*
54 TIIOS. L. CASEY.
aiigiilate posteriorly, and at the apex there is a very deeply impressed, posteriorly bifurcated puncture ; antennae slightly longer than the width of pronotum, basal joint moderately robust and elongated, second less robust and shorter, joints three to six slender, sixth much the. shortest, joints seven to eleven enlarged as a very elongated compact cylindrical club, darker in color. Prothorax nearly twice as wide as long ; sides nearly parallel and feebly arcuate ; base rather strongly arcuate and very feebly sinuate near the basal angles, which are acute ; apex broadly and evenly arcuate ; disk narrowly mai-gined posteriorly, finely, evenly, and very conspicuouslyreticulated,alsostrongly,evenly,andratherdistantlypunctate; in the middle there are four distinct impressions at the corners of a square ; just inside the posterior margin there is a transverse row of very large deeply impressed punctures. Elytra three times as long as the pronotum, rather acutely rounded behind ; disk minutely reticulated, though not as distinctly as the pronotum, very strongly punctate, punctures large, very deeply impressedandarrangedinstriae-likerows,fifthandsixthrowsdiscontinuous. Prosternum broadly and roundly emarginate anteriorly ; distance of front coxae from the emargination equal to one-half the distance between them. Length 1.8 mm.
Willets Point, Long Island ; one specimen.
This is a somewliat remarkable species ; the front coxae are more widely separated than usual. '1 he specimen described above is slightly immature, thus causing a warping of the elytra after drying ; the exact form of these parts cannot tlierefore be exactly stated. PSIXLIODES.
P. extricata n. sp. — Form elongated, narrowed behind, somewhat depressed ; body glabrous, shining, brassy-bronze above, much more piceous beneath. Head convex, moderate in size ; interocular surface almost continuousin convexity with the eyes, nearly twice as wide as the latter, feebly and evenly punctulate and minutely granulated ; eyes not at all prominent ; labruni one-third wider than long, roundly and feebly emarginate in the middle anteriorly, anterior angles rounded, surface with two feeble approximatesetigerousimpressionsinthemiddle;antennaemoderate,testaceousat base, piceous toward the tip where they are thickly pubescent, joints two, three, and four uniformly and rapidly increasing in length, fifth much shorter, sixth slightly longer than the fifth. Prothorax twice as wide as long, base one-third longer than the apex ; sides nearly straight ; base and apex broadly, evenly, rather strongly, and nearly equally arcuate ; posterior a ngles atute turn above; disk finely and evenly unctulate, and finely reticulated, punctures separated by about five times their own widths ; base narrowly and evenly margined. Scutellum sub-triangular, sides arcuate, broader than long. Elytra at base as wide as the prothorax ; sides rather strongly arcuate and convergent posteriorly ; disk four times as long as the pronotum, acutely rounded behind, strongly punctate : punctures deeply impressed and arranged in striae-like rows, distance between the rows greater than the distance between the punctures in the rows ; surface also minutely
NORTH AIMERICAN COLEOPTERA, 55 and very feebly rugulose or undulated ; epipleurae of nearly equal width throughout, not widened abruptly at base. First joint of anterior tarsi not swollen, elongated and narrower than the third, which is strongly bilobed, joints one and three spongy-pubescent beneath. Under surface of the abdomenverysparselypubescent. Length2.6nun.
New Jersey; one specimen.
The only species -with which the above described form can be compared is interstitialis Lee, and the differences are so great as to leave no doubt of its distinctness ; it will suffice here to mention one, viz. : the structure of tlie anterior tarsi, the first joint of which is greatly swollen in interstitialis and of normally slender form in extricata. P. aenescens n. sp. — Form robust, very convex ; body glabrous, highly polished, brassy-bronze above, abdomen black beneath, f«mora piceous-black, tibiae and tarsi paler. Head moderately convex ; eyes somewhat jjrominent ; interocular surface evenly convex, sparsely and minutely punctate, minutely reticulated ; labrum broadly and feebly emarginate anteriorly, having two distant impressed punctures on the upper surface, which are small, very distinct and setigerous ; antennae one-half as long as the body, reddishtestaceous at the base, becoming dark piceous-brown toward the tip, rather slender, terminal process of last joint very slender and distinct, second joint distinctly longer than the third, and about as long as the fourth. Prothorax distinctly less than twice as wide as long ; apex scarcely one-fourth shorter than the base, both broadly, evenly, nearly equally and rather strongly arcuate; sides very feebly arcuate ; posterior angles acute ; just perceptibly wider than the head anteriorly ; disk strongly convex, distinctly, evenly, and very narrowly margined posteriorly ; punctures somewhat coarse and distant, nearly evenly distributed ; surface also minutely reticulated. Scutellum small, angulate behind, sides strongly arcuate, much wider than long, steel-blue in color. Elytra at base very slightly wider than the pronotum ; disk very convex, widest at one-fourth its length posteriorly, thence gradually narrowed behind, immediate apex very obtusely rounded ; surface very strongly punctate and minutely, though rather strongly, rugulose or undulated ; punctures arranged in rows, having an irregular line of extremely minute punctures between them, distance of the ijunctures in the rows equal to about two-thirds the distance between the latter. Posterior femora very robust, and very rapidly narrowed to the apex ; first joint of the anterior tarsi moderately robust, as wide as the third, which is strongly bilobed. Length 2.1 mm.
Willets Point, Long Island; two specimens.
This species differs from interstitialis in the following particulars: — In the latter the punctuation of the head and prothorax is closer, and the punctures of the pronotum are finer ; the granulation of these surfaces is also much more distinct ; the scutellum is smaller and narrower ; the punctures of tlie elytra are much less strong and are
OG TIIOS. L. CASEY.
more distant in the rows ; the first joint of the anterior tarsi is much more swollen and is broader than the third joint ; the under surface of the abdomen and the surface of the posterior femora are more thickly pubescent ; the second joint of the antennae is distinctly shorter than the third ; in cenescens, the body, besides being smaller in size, is of a different shape ; in interstitiaJis the elytra are widest at a point one-third their length from the humeri, and the general form is slightly more elongated and less robust.
TYLODERItlA.
T. nigrum n. sp. — Form rather robust; body deep black tliroughout, moderately shining, scarcely metallic ; tibiae dark fuscous. Head moderately convex, rather coarsely and feebly punctate, very sparsely so in the middle, more densely at the sides ; rostrum very robust, anterior surface broadly impressed at the base, coarsely and longitudinally rugulose or furrowed, entire surface minutely granulose. Prothorax just perceptibly wider than long; sides just visibly divergent from the basal angles for two-fifths the length anteriorly, then rather suddenly and strongly constricted ; very evenly and strongly arcuate anteriorly when viewed vertically, base very broadly and feebly arcuate ; Hanks perpendicular, strongly swollen just over the anterior coxae, edge sinuate anteriorly, emargiuate for the coxae at the sides : disk of pronotum very sparsely punctate dorsally, where the punctures are round, small, impressed, and much finer anteriorly than toward the base ; on the flanks the punctures are very irregularly distributed, much coarser, deeper, and generally closer ; surface minutely granulose, feebly shining. Scutellum longer than wide, convex, angulate behind. Elytra at the humeri slightly more than one-third wider than the contiguous pronotum ; sides parallel and very feebly arcuate for one-half the length, then gradually convergent; disk acutely rounded behind, very convex, scarcely more than one-lialf longer than wide, slightly more than twice as long as the pronotum ; punctures large, deeply impressed, round, arranged in rows, distances of the punctures in the sutural rows much less than in the others : flanks inflexed ; edges not bordered, nearly straight laterally, acute ; viewed from beneath, the edges are very broadly cusped, cusp broadly rounded and placed at the sides of the third ventral segment. Under surface of abdomen sparsely punctate, slightly more densely so on the last segment, first two segments together slightly longer than the last three ; metasternum very coarsely, deeply, and rather sparsely punctate, very coarsely granulose. Length 3.8mm.
^Northern Illinois.
This species diHers from cereinn and baridnm in facies. One of the numerous structural differences is shown in tigs. 10, 11, and 12, plate I., which represent the relations existing between the mesosternal and metasternal episterna, and the mesosternal epimeron in the three species respectively. It is seen that, while the mesosternal