CHRYSICHTHYS. 31 =I B. Base of adipose fin 1% to 3 times in its distance from rayed dorsal. 1. Head 12 to 1} times as long as broad.
a. Width of mouth 14 to 12 times in length of head; 10-13 gill-rakers on lower part of anterior arch.
Caudal deeply notched; anal with 8-10 branched rays; head rugoseabove . . . . . . 13. C. eranchit, Leach, p. 332. Caudal deeply notched; anal with 7 branched rays; head rugose above . . . . . . 14. C. punctatus, Blgr., p. 334. Caudal feebly notched ; anal with 7 branched rays; head nearly smooth above . . . 15. C. delhezi, Blgr., p. 335. b. Width of mouth twice in length of head; 16 gill-rakers on lower part of anterior arch ; anal with 7 branched rays. . . . . . 16. C. mabusi, Bler., p. 336. 2. Head not more than 1} times as long as broad. Maxillary barbel at least as long as head ; anal with 6-8 branched rays; head rugose above; 9-10 gill-rakers on lower part OwanbenOnarche wees se ra ee Lie OC monnanue: Blot. insole Maxillary barbel 4 to # length of head ; anal with 8-10 branched rays; head rugose above ; 12-20 gill-rakers on lower part of aMbeLOrrarche ares) Wet (een ae lal Onmiyneodon. BIOL. ps Oooe Maxillary barbel 1 to 4 length of head; anal with 8-9 branched rays; head smooth above; 13-18 gill-rakers on lower part of antenlonanchyoy oii) Ween iy 3) 9G Courachynemna, lon. pase. 1. CHRYSICHTHYS SIANENNA.
Bouleng. Trans. Zool. Soe. xvii. 1906, p. 551, pl. xxxii. fig. 2. Depth of body 54 to 6 times in total length, length of head 44 times. Head moderately depressed, 12 to 14 times as long as broad, smooth above; occipital process narrow, nartowly separated from the smal} interneural shield; snout rounded, projecting a little beyond lower jaw, x length of head; eye 4 to 44 times in length of head, 1 to 13 times in interorbital width; width of mouth about 4 length of head ; premaxillary band of teeth curved, 6 times as long as broad; vomeropterygoid teeth forming a long and narrow crescentic band; nasal barbel 4 diameter of eye; maxillary barbel 12 to 14 times length of head; outer mandibular barbel nearly twice as long as inner and 4 length of head. Gill-rakers long and closely set, 18 to 20 on lower part of anterior arch. Dorsal I 6, rather small, nearly twice as distant from
318 SILURID.
root of caudal as from end of snout; spine rather feeble, serrated behind, $ length of head; first soft ray longest, 3 to 3 length of head. Adipose dorsal 2 to 3 times as long as deep, its base equal to or a little longer than that of the rayed dorsal, from which it is separated by a space equal to 3 or 4 times its base. Anal 14, 10 rays branched. Fig.250.
@ Chrysichthys stanenna.
Type (‘I'r. Z. 8. 1906). 4.
Pectoral spine about 2 length of head, feebly serrated on outer side, more strongly on inner side. Caudal deeply forked, with pointed lobes, longest rays 5 to 35 times length of median. Caudal peduncle twice as long as deep. Olive above, silvery white beneath. Total length 220 millim.
Lake Tanganyika.
1-2. Types. Niamkolo. Dr. W. A. Cunnington (C.). 3. Dype. Mbete. Bs 2, CHRYSICHTHYS SHARPII.
Bouleng. Ann. & Mag. N. H. (7) vii. 1901, p. 81, and Poiss. Bass, Congo, p. 281 (1901).
Depth of body 5} times in total length, length of head 4 times. Head much depressed, 14 times as long as broad, feebly granulate above; occipital process a little longer than broad, extending to the small interneural shield; snout broadly rounded, projecting a little beyond lower jaw, 4 length of head; eye oval, 6 times in Jength of head and twice in interorbital width; width of mouth twice in length of head; premaxillary band of teeth curved, 6 times as long as broad; vomero-pterygoid band narrow, crescentic, scarcely interrupted in the middle; nasal barbel 3 diameter of eye; maxillary barbel 2 length of
CHRYSICHTHYS. 319 head; outer mandibular barbel 14 times as long as inner and = length of head. Dorsal I 5, 14 times as distant from root of caudal as from end of snout; spine striated, not serrated, + length of head; first soft ray longest, ¢ length of head. Adipose dorsal not longer than deep, its base 4 that of rayed dorsal, from which it is separated by a space equal to 7 times its base. Anal 13,8 rays branched. Pectoral spine } length of head, strongly serrated on inner side. Caudal deeply forked, with pointed lobes, longest rays about 3 times length of median, Caudal peduncle not quite twice as long as deep. Brown above, whitish beneath.
Total length 570 millim.
Lake Mweru.
1. Skin, type. L. Mweru. Sir A. Sharpe (P.).
3. CHRYSICHTHYS ACUTIROSTRIS.
Giinth. Cat. Fish. y. p. 431 (1864).
Depth of body 55 times in total length, length of head 34 times. Head but slightly broader than deep, 12 times as long as broad, its Fig.251.
Chrysichthys acutirostris.
Type. i.
upper surface rugose; occipital process narrow, extending to the small interneural shield; snout obtusely acuminate, not broader than long, _nearly twice as long as eye, which is 43 times in length of head and
520 SILURID.
equals interorbital width; mouth inferior, its width 34 times in length of head; premaxillary band of teeth straight, 3 times as long as broad ; two small, widely separated groups of teeth on the vomer; nasal barbel 3 diameter of eye; maxillary barbel 2 length of head; outer mandibular barbel 3 length of head, inner +. Gill-rakers moderate, 14 on lower part of anterior arch. Dorsal I 6, 14 times as distant from root of caudal as from end of snout; spine about } length of head, rugose in front, strongly serrated behind; first soft ray longest, ? length of head. Base of adipose dorsal a little shorter than that of rayed dorsal, from which it is separated by a space equal to 2} times its base. Anal 14, 9 rays branched. Pectoral about # length of head; spine feebiy granulate on outer border, strongly serrated on inner. Caudal deeply forked, with pointed lobes, upper the longer, more than 3 times as long as middle rays. Caudal peduncle twice as long as deep. Brown above, silvery white below.
Total length 205 millim.
Golungo Alto, Angola.
1. Type. Golungo Alto. Dr. Welwitsch (P.).
4, CHRYSICHTHYS FURCATUS.
Giinth. Cat. Fish. v. p. 430 (1864) ; Steind. Sitzb. Ak. Wien, Ixi. i, 1870, p. 992, pl. vili.; Bouleng. Poiss. Bass. Congo, p. 280 (1901). Chrysichthys camaronensis, Giinth. Proc. Zool. Soc. 1899, p. 729, pl. xliv. Depth of body 4% to 6 times in total length, length of head 34 to 32 times. Head moderately depressed, 14 to 14 times as long as broad, smooth or feebly rugose above; occipital process narrow, extending to the small interneural shield; snout rounded, broader than long, once (young) to 3 times as long as eye, which is 4 (young) to 64 times in length of head and once to twice in interorbital width; mouth inferior, its width 24 to 3 times in length of head; premaxillary band of teeth nearly straight, 3 to 4 times as long as broad; vomero-pterygoid teeth forming a long band interrupted in the middle, its width equal to or a little less than that of the premavillary band in the adult; nasal barbel 2 to once diameter of eye; maxillary barbel } to 3 length of head; outer mandibular barbel 15 times as long as inner, 3 to } length of head. Gill-rakers rather long, 15 to 20 on lower part of anterior arch. Dorsal I 6, 14 to 14 times as distant from root of caudal as from end of snout; spine # to 4 length of head, smooth in front, very feebly serrated
CHRYSICHTHYS. 321 behind; second or first and second soft rays longest, nearly as long as head or shorter. Base of adipose fin } to # that of dorsal, from which it is separated by a space equal to 2 to 4 times its base. Anal 14-16, 9-11 rays branched. Pectoral 3 to # length of head; spine strongly serrated on inner border. Caudal deeply forked, with pointed lobes, Chrysichthys furcatus.
1 Ty pe- 3.
longest rays 3 to 4 times as long as middle rays. Caudal peduncle 14 to 2 times as long as deep. Dark grey above, white beneath. Total length 470 millim.
West African Rivers, from the Senegal to the Congo. 1-2. Ad. Gambia. J.S. Budgett, Hsq. (P.). 3-4. Ad. Ogun R. at Aro, 8. Nigeria. Major G. E. Bruce (P.). 5. Ad., type. Niger. Mr. J. T. Dalton (C.). 6. Ad., type of Cameroon. Mr. C. L. Salmin (C.). C.
camaronensis.
7. Her. Banana, Congo. M. P. Delhez (C.). 8. Yg. Boma, ie 5 Oh Wyse, Landana, ,, Dr. Jackson (C.) ; Hon. W. Rothschild (P.).
5. CHRYSICHTHYS NIGRODIGITATUS. Pimelodus nigrodigitatus, Lacep. Hist. Poiss. vy. pp. 102 & 108 (1803). Bagrus maurus, Cuy. & Val. Hist. Poiss. xiv. p. 431 (1539). VOL, II, Y
322 SILURID®.
Arius acutivelis, Cuy. & Val. Hist. Poiss. xv. p. 85 (1840) *. Melanodactylus nigrodigitatus, Bleek. Nederl. Tijdschr. Dierk. i. 1863, p. 95. Chrysichthys nigrodigitatus, Giinth. Cat. Fish. y. pp. 73 & 430 (1864); Steind. Sitzb. Ak. Wien, Ix. i. 1870, p. 989, pl. vii., and Notes Leyd. Mus. xvi. 1894, p- 59; Giinth. Proc. Zool. Soc. 1899, p. 727.
Chrysichthys macrops, part., Giinth. Ann. & Mag. N. H. (8) xx. 1867, p. 112. Chrysichthys buttikoferi, Steind. Notes Leyd. Mus. xvi. 1894, p. 60, pl. i. fig. 1; Giinth. Ann. & Mag. N. H. (6) xvii. 1896, p. 276, and Proc. Zool. Soc. 1899, p- 721, pls. xli. & xiii. fig. A.
Chrysichthys ogowensis, Giinth. Proc. Zool. Soe. 1899, p. 723. Chrysichthys coriscanus, Giinth. t.e. p. 72+.
Chrysichthys lagoensis, Giinth. t. e. p. 725, and 1902, ii. p. 335, fig. Depth of body 4 to 5 times in total length, length of head 523 to 3% times. Head feebly depressed, 14 (young) to 1} times as long as broad, Fig.253.
Chrysichthys nigrodisitatus, After Steindachner (Sitzb. Ak. Wien, 1870). 4.
its upper surface more or less rugose, the rugosities usually showing uuder the thin skin; occipital process narrow, extending to the small * T have examined the types of A. acutivelis=melanodactylus (160 millim., very badly preserved) and B. mawrus (195 millim.) in the Paris Museum. In both the dentition of the palate is reduced to two small groups of vomerine teeth. Larger specimens (220- 340 millim.) from the Senegal (Heudelot) and Goree (Rang) haye a small group of teeth oneachentopterygoid,widelyseparatedfromthevomerine.
i) CHRYSICHTHYS. 325) C interneural shield ; snout obtusely pointed, not much broader than long; eye large, transversely oval, its diameter 1 (young) to 2} times in length of snout, 3 to 6 times in length of head, not more than 14 times in interorbital width; mouth inferior, its width 24 to 4 times in length of head; premaxillary band of teeth straight, } to 3} times as long as broad; vomero-pterygoid teeth forming a narrow band interrupted in the middle, sometimes reduced to the vomerine part; nasal barbel 4 to + diameter of eye; maxillary barbel $ to 3 length of head; outer mandibular barbel a little longer than inner, 2 to # the length of the maxillary barbel. Gill-rakers rather long, 12-17 on lower part of anterior arch. Dorsal I 6, 14 to 14 times as distant from root of caudal as from end of snout; spine 4 to $ length of head, smooth or granulate in front, rather feebly serrated behind; second soft ray longest, ? to 14 times length of head. Base of adipose fin shorter than that of dorsal, from which it is separated by a space equal to 2 to 4 times its base. Anal 12-14, 8 or 9 (rarely 7) rays branched. Pectoral 2 to + length of head; spine smooth or fecbly granulate on outer border, strongly serrated on inner. Caudal deeply forked, upper lobe longest and often produced into a filament, at least 3 times as long as middle rays. Caudal peduncle 13 to 13 times as long as deep. Dark grey or brown above, silvery white beneath; a more or less indistinct dark transverse band behind the head and another in front of the dorsal fin. Total length 370 millim.
West Africa, from the Senegal to the Ogowe.— ‘Type in Paris Museum.
1-2. Ad. St. Louis, Senegal. M. P. Delhez (C.).
3. Her. Kaédi, i “ 4-10. Ad., hgr., & yg. Gambia. J.S. Budgett, Esq. (P.). 11, 12-15. Ad. & yg. R. Prah, Gold Coast. R. B. N. Walker, Esq. (P.). 16-24. Yg. R. Offin, hs Kt 25. Her. Nyankoma, _,, z, 26. Ad., type of Lagos. H. T. Ussher, Esq. (C.). C.
lagoensis.
27, 28. Ad. & yg. Niger. Mr. J. T. Dalton (C.).
99. Ad. Lokoja, Upp. Niger. J.S. Budgett, Esq. (P.). 30h Mee Assay, Low. Niger. Dr. W. J. Ansorge (C.). BUS Sia Sapelle, Me a 33. Yg. Benue R., North of Ibi. H. 1. Norton Traill, Esq. (C.). 34. Her. Enyong R., Old Calabar. Major W.A.C.Cockburn(P.). 35, Ad. Kribi R., Cameroon. G. L. Bates, Esq. (C.). y2
324 SILURID A.
36-37. Yo., types of Corisco Id. Miss Kingsley (C.). C.
coriscanus.
38. Yo. Benito R. G. L. Bates, Esq. (C.). 39. Skel. A ‘ 40. Her., type of Kondo Kondo, Ogowe. Miss Kingsley (C.). C.
ogowensis.
41. Her. Lambarene, Ogowe. Dr. W. J. Ansorge (C.). 42. Yo. Negomo, Ogowe. Rey. Hi. Haug (C.) ; Paris Museum (f.).
6. CHRYSICHTHYS WALKERTI.
Chrysichthys macrops, part., Giinth. Ann. & Mag. N. H. (3) xx. 1867, p. 112. Chrysichthys auratus, part., Giinth. Proc. Zool. Soe. 1899, p. 718. Chrysichihys watkeri, Giinth. t. ce. p. 720, fie. Chrysichthys persimilis, Giinth. t. e. p. 727, pl. xiii. Chrysichthys kingsleye, Giinth. t. c. p. 728, pl. xlv. fig. A. Depth of body 4 to 5 times in total length, length of head 3 to 3$ times. Head moderately depressed, 14 to 14 times as long as broad, more or less rugose above; occipital process narrow, in contact with Fig.254.
Chrysichthys walkert.
Type of C. persimilis. 4, interneural shield; snout rounded, much broader than long, once (young) to twice diameter of eye, which is 54 to 5 times in length of head and at least equals interorbital width ; width of mouth 2 to 2§ times in length