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Show 200 MR. G. A. BOULENGER ON THE [Feb. 2, 4. On the Type Specimen of a West African Fish, Clarias Iceviceps Gill. By G. A. B O U L E N G E R , F.R.S., V.P.Z.S. [Received January 9, 1904.] The name Clarias Iceviceps was introduced by Gill in Proc. Ac. Philad. 1862, p. 139, for a small fish in the Collection of the Smithsonian Institution, bearing no indication of locality, but regarded as probably from Liberia. The definition is given in the following words :-•' Height at anus a tenth of length ; head (laterally) a sixth; its breadth an eighth; the surface smooth; maxillary barbels twice as long as head. D. 86. A. 61." In a genus represented in West Africa by so many closely allied species, so brief a definition could hardly answer its purpose, and Clarias Iceviceps has proved a stumbling-block to workers at African ichthyology. Sauvage recognised the species in a specimen from the Gold Coast; Giinther suggested its identity with C. bythi-pogon of Sauvage ; and I myself proposed to regard it as a synonym of C. sake, described by Hubrecht from Liberian specimens. But all this was mere guesswork, and lately, when describing another close ally, under the name of C. pachynema, I felt it imperative to settle the matter by an appeal to the type specimen preserved in the U.S. National Museum. I am glad to say that m y application was granted, in a most courteous manner, by the Assistant Secretary of that Institution, notwithstanding the rule that unique type specimens are not to be sent on loan. I must add that the exception made in my favour is greatly due to the kind advocacy of Dr. Theo. Gill, the original describer of the specimen. I beg to tender m y sincei'e thanks to the authorities of the Smithsonian Institution and to Dr. Gill for their gx-eat kindness. I here give a description of tlxe type of C. Iceviceps, followed by a comparative description of three further specimens, viz. the types of C. kingsleyce Gthr., and the specimen from Assini, Gold Coast, coxrectly identified by Sauvage. CLARIAS L^VICEPS. Gill, Px-oc. Ac. Philad. 1862, p. 139. Depth of body 8| times in total length, length of head 5 times. Head once and \ as long as broad, smooth ; occipital process pointed; frontal fontanelle sole-shaped, not quite twice as long as broad ; occipital fontanelle smallex-, in advance of occipital process; eye very small, 3 times in length of snout, 6 times in interorbital width, which equals half length of head and a little exceeds width of mouth ; band of prasmaxillary teeth 5 times as long as broad ; vomei-ine teeth conical, forming a curved band which is a little narrower than the praemaxillary band ; barbels rather thin, nasal nearly half length of head, maxillary once and f, outer mandibular once, inner mandibular not quite §. Gill-rakers few, about 20 on first arch. Clavicles concealed under the skin. Dorsal fin 87 its |