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Show 1902.] FISHES FROM THE GOLD COAST. 331 3. Bokitsa Mine-are two small rivers and a locality in the Wasa district. 4. Ingogosu is described on the label as a village in the mining centre of Kinkiankwa. 5. Infoan, a small place on a tributary of the River Offim. 6. Dunkwa, a place on the River Offim or on one of its tributaries. Mr. Walker speaks of it sometimes as a place and sometimes as a river. There is another place with the same name north and inland of Cape Coast Castle. 7. Odumasi, a place on the upper part of the River Enon, east of Koumassi. 8. Lake Busum-chi. 9. Nyankoma, a place on the River Enon. 10. Town of Akropon. Mr. Walker's connection with commercial affairs on the West Coast of Africa extended over a period of more than forty years, the greater part of which he resided in the country. It seems that the late Mr. T. Moore, Curator of the Liverpool Museum, was the first to interest him in making collections of Reptiles and Fishes. He retained this interest to the end of his life, much advancing our knowledge of the fauna of the Gaboon country and the Gold Coast; and there is no doubt that he would have accomplished still more if circumstances had permitted us to supply him with more ample means than were at his disposal, while, moreover, the primary objects of his pursuits demanded nearly all his time and energy. C h r o m is o g o w e n s is . Chromis ogoivensis Giinth. Ann. & Mag. N. H. 1896, xvii. p. 271 ; Proc. Zool. Soc. 1899, p. 717. This species is not to be united with C. latus, to which it has been referred by Boulenger (Proc. Zool. Soc. 1899, p. 125). In a smaller specimen of C. latus the anterior maxillary teeth are absolutely larger than, and the anterior mandibulary teeth as large as, the corresponding teeth of larger specimens of C. ogoivensis \ The pectoral fin may be rather shorter or rather longer than the head ; it generally does not reach the anal. Mr. Walker's latest collection contains several additional 1 In treating of the species of Chromis in the Congo, Mr. Boulenger (Poiss. du Congo, p. 453) states that for specific discrimination no reliance is to be placed on the number of teeth in the outer premaxillary series ■ first, because it varies selon les individus," and secondly, because as a rule the teeth are relatively smaller and more numerous in adult than in young specimens. The first statement is opposed to my experience. There are broad-toothed and narrow-toothed species; but, of course, there is some variation even in the former, and the limits of variation widen in species characterized by small and numerous teeth, in which case it is not even desirable or useful to attempt to state the number of teeth. That young individuals have a smaller number than adult is true, as I also have already stated in Proc. Zool. Soc. 1896, p. 217, but this dental development cannot be called variation; with the advancing growth of the jaws more teeth are added laterally. I continue to |