CHRYSICHTHYS.—CLAROTES. O41 premaxillary band of teeth scarcely curved, 5 to 6 times as long as broad ; vomero-pterygoid teeth forming a long and broad band, uninterrupted or narrowly interrupted mesially, strongly widening posteriorly in the adult, narrowed and tapering behind in the young; nasal barbel 3 to 15 times diameter of eye; maxillary barbel 4 to} length of head ; outer mandibular barbel 4 to } length of head, inner} to 4. Gill-rakers moderate, 13-18 on lower part of anterior arch. Dorsal I 6, a little nearer end of snout than root of caudal ; spine 2 length of head, very feebly serrated in front and behind, covered with thick skin; first, second, and third soft rays equal, about 3 length of head. Adipose fin 1} to 2 times as long as deep, its base hardly equal to that of dorsal, and } to 4 its distance from the latter. Anal 12-13, 8 or 9 rays branched. Pectoral spine thicker and longer than dcrsal, strongly serrated on inner side. Caudal deeply notched, with obtusely pointed lobes, longest rays 2 to 25 times length of median. Caudal peduncle 1} tu 1% times as long as deep. Olive above, white beneath.
Total length 400 millim.
Lake Tanganyika.
1-3. Ad. & her., types. Kalambo. Prof. J. E. 8. Moore (C.). 4. Her., type. Usumbura. Hp 5. Her. Niamkolo. Dr. W. A. Cunnington (C.).
16. CLAROTES.
Kner, Sitzb. Ak. Wien, xvii. 1855, p. 313; Giinth. Cat. Fish. v. p. 73 (1864) ; Bouleng. Fish. Nile, p. 339 (1907).
Gonocephalus, Kner, 1. ¢.
Octonematichthys, Bleek. Act. Soc. Sc. Ind.-Neerl. iv. 1858, p. 60, and Nederl. Tijdschr. Dierk. i. 1863, p. 95.
Distinguished from Chrysichthys only by the presence of rays (one thick anterior spinous ray and several articulated soft rays) in the adipose dorsal fin. But there is no sign of these rays in very young specimens, the adipose fin of which cannot be distinguished from that of a Chrysichthys ; they first appear as slender, hair-like, horny filaments, and they are gradually transformed into structures similar to those of the anterior dorsal fin, except that they are deprived of endoskeletal supports or baseosts; the spine is formed by the fusion of fulcra-like scutes.
Vertebre 43 (19-424), A single species.
342 SILURIDZA.
1, CLAROTES LATICEPS.
Pimelodus laticeps, Riipp. Beschr. n. Fische Nil, p. 7, pl. i. fig. 2 (1829). Bagrus nigrita, Cuy. & Val. Hist. Poiss. xiv. p. 426, pl. eecexvi. (1839). Bagrus laticeps, Heckel, Russegger’s Reise Egypt. ii. p. 381 (1849). Clarotes heuglinii, Kner, Sitzb. Ak. Wien, xvii. 1855, p. 313, pls. i. & ii. ; Hyrtl, Denkschr. Ak. Wien, xvi. 1858, p. 1, pl. —; Kner, Arch. f. Naturg. 1865, i. p. 101.
Octonematichthys nigrita, Bleek. Act. Soe. Se. Ind.-Neerl. iv. 1858, p. 65. Clarotes laticeps, Giinth. Cat. Fish. v. p. 73 (1864), Zool. Rec. 1866, p. 150, and Petherick’s Trav. ii. p. 231 (1869) ; Vincig. Ann. Mus. Genova, (2) xv. 1895, p- 39, xvii. 1896, p. 27, and 1897, p. 349; Bouleng. Fish. Nile, p. 340, pl. lsi. (1907).
Chrysichthys cranchii (non Leach), Steind. Sitzb. Ak. Wien, Ix. 1. 1870, p. 987. Chrysichthys nigrita, Sauv. N. Arch. Mus. (2) iii. 1880, p. 40. Depth of body 4+ to 52 times in total length, length of head 24 to 34 times. Head much depressed, 14 to 14 times as long as broad, its Fig.267.
Clurotes laticeps.
White Nile (F. N.). 4.
upper surface rugose with fine granulations, which are most crowded on the occiput; operculum with radiating strive ; occipital process as long as broad, nearly as long as the small interneural shield with which it is in contact; snout broad, rounded or truncate; eye large, transversely oval, 1 (young) to 5 times in length of snout, 1} to 5 times in interocular width; mouth inferior, its width equal to or a little greater
CLAROTES. 343 than interocular width ; premaxillary band of teeth 5 to 7 times as long as broad; vomero-pterygoid teeth forming a narrow band, often narrowly interrupted in the middle, sometimes also on the sides. Nasal barbel 4 to 2 length of head; mavillary barbel flattened, band-like at base, nearly 1 to 12 times leneth of head ; outer mandibular barbel 1} to 14 times as long as inner, + to nearly once length of head. Gillrakers rather long, 16-22 on lower part of anterior arch. Humeral process short, acutely pointed, granulate. Dorsal I 6; spine strong, feebly serrated behind in the young, with granulations in front in the adult, } to 2 length of head; first soft ray longer, but always shorter than head. Second dorsal short, deeper than long, its distance from the first about twice as great as basal length of latter; the rays not distinct in specimens under 100 millim. total length, the strong anterior spine fully ossified in specimens over 400 millim. Anal 12-14, 7 or 8 rays branched. Pectoral much shorter than head, not reaching ventral, with a strong spine bearing 5 (young) to 18 serre on inner side; these serre much stronger in proportion in young than in adult, which have a fine serration on outer edge. Ventral much nearer root of cauda) than end of snout. Caudal deeply forked, lobes acutely pointed in young, more obtusely, or even rounded, in adult. Caudal peduncle as long as deep or a little longer than deep. Tubes of lateral line strongly branched. Brown above, silvery white below; a blackish spot above the humeral process ; a brown or blackish band on each lobe of the caudal fin. Total length 570 millim.; grows to 800. Upper Nile, Blue Nile, White Nile, Bahr-el-Gebel, Webi Shebeli, Tana and Gana (Hast Africa), Chad Basin, Senegal, Niger—Type in Senckenberg Museum, Frankfort/M. Egor 2,3, 4-5. Ad. & ygS 6. Her.
dpSyNee Sly, Wee 10. Yg.
MilWee 12. Skel.
13-14. Yv.
15-21. Her. & yg.
22. Ad.
23. Ad.
24-26. Yo.
Between Luxor and Assuan. Khartum.
Omdurman.
Wad Medine, Blue Nile. Rosaires, Blue Nile. Mangara, White Nile. Kawa, a ) bb) Nur-ed-Dain, White Nile. Goz abu Gumah, White Nile. Jebelain, bi Gharb-el-Aish, 1 Fashoda, 5 L. Loat, Esq. (C.). J. Petherick, Esq. (C.). L. Loat, Esq. (C.). Capt. 8. Flower (P.). L. Loat, Esq. (C.). chy}
a44 SILURIDA, 27. Ad. Gondokoro, Bahr-el-Gebel. 28-29. Ye. Neatana, Tana R. 30. Head of ad. L. Chad. 31-32. Her. Kano, Hadeija R., Chad Basin.
33. Ad. St. Louis, Senegal. 34-36. Yo. Kaédi, - Ole Ad: Niger.
38. Ad. Bs 39-41. Ad. & her. Mureji, Upp. Niger. 42. Her. Oguta, Low. Niger. 43-45. Yg. Abo, a 46. Yg. R. Benue, N. of Ibi. 17. GEPHYROGLANIS.
Bouleng. Ann. Mus. Congo, Zool. i. p. 42 (1899), and Poiss. Bass. Congo, p. 292 (1901).
L. Loat, Esq. (C.).
Prof. J. W. Gregory (P.). Capt. G. B. Gosling (P.). 9 M. P. Delhez (C.).
Mr. J. T. Dalton (C.). W. A. Forbes, Esq. (P.). J. S. Budgett, Esq. (P.). Dr. W. J. Ansorge (C.). H. L. Norton Traill, Esq. (>):
Distinguished from Chrysichthys by the absence of teeth on the palate. Nasal barbel short, sometimes hardly developed. Tropical and South Africa. Synopsis of the Species. T. Nasal barbel } to } diameter of eye ; maxillary barbel shorter than head. a. Maxillary barbel not more than 3 length of head; folded dorsal fin not extending totheadipose.
Anal with 8 branched rays; adipose fin a little shorter than rayed dorsal ; caudal with acutely pointed lobes ; occiput feebly granulate Anal with 10 branched rays; adipose fin a little longer than rayed dorsal; caudal with acutely pointed lobes ; four longitudinal ridges on the vertex ; occiput strongly rugose . a Anal with 11 to 13 branched rays; adipose fin longer than rayed dorsal ; caudal with obtuse lobes ; headsmooth.
6. Maxillary barbel a little shorter than head ; folded dorsal reaching adipose ; anal with 8 branched rays ; caudal with acutely pointed lobes ; occiput striated . bo (3) . G. congicus, Blgr., p. 345. [p.346.
. G. ogoensis, Pellegr., . G. sclateri, Blgr., p. 346. (r. tilhoi, Pellegr., p. 848.
GEPHYROGLANIS. 345 II, Nasal barbel 4 to } diameter of eye ; maxillary barbel a little longer than head; folded dorsal reaching adipose, which is shorter ; anal with 8 or 9 branched rays ; caudal with acutely pointed lobes ; vertex and occiput strongly [p. 348. striated and granulate... .. .. . % G. longipinnis, Blgr., 1. GEPHYROGLANIS CONGICUS.
Bouleng. Ann. Mus. Congo, Zool. i. p. 42, pl. xx. fig. 2 (1899), and Poiss. Bass. Congo, p. 292, pl. xiv. fig. 2 (1901).
Depth of body 51 times in total length, length of head 4 times. Head depressed, 12 times as long as broad, smooth except on the occiput, which is feebly granulated and striated, and on the operculum, which is striated ; occipital process as long as broad, in contact with interneural shield ; snout obtusely conical, 2 length of head; eye oval, 32 (young) to 6 times in length of head, twice in interorbital width ; Fig.268.
i Z Gephyroglunis congicus.
Type (A. M.C.). 3.
nasal barbel very small, not 4 diameter of eye; maxillary barbel hardly half length of head; outer mandibular barbel 3 length of head and about twice as long as inner; mouth not quite + width of head; premaxillary band of teeth straight, short and broad. Dorsal I 6, longest ray shorter than head; spine % to 2 length of head, not serrated or feebly serrated behind in the young. Adipose fin 1} times as long as deep, a little shorter than rayed dorsal, its base 25 times in its distance from the latter. Anal 12, 8 rays branched. Pectoral spine $ length of head, feebly serrated on inner border in the adult, strongly in the young. Caudal deeply forked, with pointed lobes. Caudal
346 SILURID®.
peduncle a little over twice as long as deep. Brownish above, white beneath.
Total length 480 millim.
Upper Congo.—Type in Congo Museum, Tervueren.
2. GEPHYROGLANIS OGOENSIS.
Pellegr. Bull. Mus. Paris, 1900, p. 179, and Bull. Soc. Philom. (9) x. 1908, p-187.
Depth of body 5 to 53 times in total length, length of head 34 times. Head nearly as deep as broad, 1? times as long as broad, with four longitudinal ridges on the vertex and strong rugosities on the occiput, to which the skin is adherent; occipital process much longer than broad, in contact with interneural shield; snout obtusely conical, more than 2 length of head; eye oval, twice in snout, 43 times in head, 1+ to 14 times in interocular width; nasal barbel 4} diameter of eye; maxillary barbel 2 length of head, outer mandibular 3, inner mandibular ?; mouth 4 width of head; premaxillary band of teeth straight, nearly 4 times as long as broad. Dorsal I 6, not reaching adipose fin when folded, longest soft ray # Jength of head; spine strong, striated, feebly serrated behind, 3 length of head. Adipose fin about twice as long as deep, as long as or a little Jonger than rayed dorsal, its base once and 2 to twice and 4 in its distance from the latter. Anal 15, 10 rays branched. Pectoral spine a little shorter than dorsal, strongly serrated on inner border. Caudal deeply forked, longer than head, with long pointed lobes. Caudal peduncle twice as long as deep *. Total length 250 millim.
Aduma, Ogowe.—Type in Paris Museum.
3. GEPHYROGLANIS SCLATERI.
Bouleng. Ann. 8. Afr. Mus. ii. 1901, p. 228, pl. xiii. Depth of body 5 to 6 times in total length, length of head 4 times. Head 1} to 14 as broad as deep, 11 to 14 times as long as broad, perfectly smooth ; occipital process much longer than broad, in contact with the interneural shield; snout obtusely conical, 2 length of head; eye 5 to 6 times in length of head, 14 to 12 times in interocular width ; nasal barbel very short, barely 4 diameter of eye; maxillary barbel } to 3 3B 2 * Described from the type specimen and another, from the same locality, named “Chrysichthysnigrodigitatus”intheParisMuseum.
9 GEPHYROGLANIS. 347 length of head, outer mandibular }, inner }. Mouth 3 to } width of head ; premaxillary band of teeth curved, 3 to 4 times as long as broad. Dorsal I 7, 13 to 2 times as deep as long, not reaching adipose fin when folded; spine strong, smooth, 3 to # length of head; longest soft ray a little shorter than head. Adipose fin about 3 times as long as deep, a little shorter than its distance from the dorsal, Anal 16-17, 11-13 rays branched. Pectoral spine a little shorter than dorsal, strongly serrated on inner border. Caudal forked, with obtuse lobes, shorter than the head. Caudal peduncle 14 times as long as deep. Uniform brownish or green above, whitish beneath.
Total length 190 millim.
Orange River System.—Type in S. African Museum, Cape Town. Gephyroglanis sclateri.
Type (Ann. 8. Afr. Mus. 1901). 3.
1. One of the types. Vaal R., Transvaal. S. African Museum (P.). 2-3. Ad. & her. Vaal R. at Standerton, Transvaal. S. Pershouse, Esq. (P.). 4, Skel. me 3 i BS 5. Ad. Mooi R. at Potchefstroom, Trans- Capt. Stenning (C.). vaal.
6. Ad. Mooi R., Transvaal. Dr, J. D. F. Gilchrist (P.). 7. Ad. Kraai R., Cape Colony. 3
348 SILURID&.
“ 4. GEPHYROGLANIS TILHOT.
Pellegr. Bull. Mus. Paris, 1909, p. 243.
Depth of body 5 times in total length, length of head 34 times. Head depressed, slightly striated on occiput and opercle; occipital process longer than broad and in contact with interneural shield; snout as long as eye, which is oval, hardly more than 3 times in length of head, and exceeds a little interorbital width; nasal barbel minute, quite rudimentary; maxillary barbel a little shorter than head; outer mandibular barbel a little longer than inner and nearly 4 length of head; mouth about + width of head. Dorsal I 6, reaching adipose fin when folded, first soft ray produced into a filament, much longer than head; spine 2 length of head. Base of adipose fin 12 times in its distance from rayed dorsal. Anal 11, 8 rays branched. Pectoral spine about 4 length of head, strongly serrated on inner border. Caudal deeply forked, with pointed lobes. Caudal peduncle a little longer than deep.
Total length 118 millim.
Lake Chad.—Type in Paris Museum.
5. GEPHYROGLANIS LONGIPINNIS.
Bouleng. Ann. Mus. Congo, Zool. i. p. 109, pl. xli. fig. 4 (1899), and Poiss. Bass. Congo, p. 293 (1901).
Depth of body 4% to 5 times in total length, length of head 3 to 34 times. Head moderately depressed, 15 times as long as broad, rather strongly granulated and striated above; occipital process as long as broad, in contact with interneural shield; snout obtusely conical, as long as eye; latter oval, about 5 times in head, 1 to 1% times in interocular width ; nasal barbel 4 to 4 diameter of eye; maxillary barbel a little longer than head; outer mandibular barbel ? length of head and not quite twice length of inner; mouth 4 width of head ; praemaxillary band of teeth straight, about 3 times as long as broad. Dorsal I 6, reaching origin of adipose fin when folded, first and second soft rays as long as head; spine # length of head, feebly serrated behind. Adipose fin about as long as deep, 3 to } base of rayed dorsal, its base 2 to 24 in its distance from the latter. Anal 15-14, 8 or 9 rays branched. Pectoral spine 3 length of head, strongly serrated on inner border. Caudal deeply forked, with pointed lobes. Caudal peduncle 1} to 13