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On some Young Specimens of Centrolophus pompilus 

 (Art.) from the Coast of Cornwall. 



By 



Ernest W. li. Holt. 



On the 24tli June, 1891, a mackerel boat, which had been fishing 

 off the Runnistone, brought in several fish of the above species. 

 They excited a good deal of interest among the local fishermen, to 

 whom they were quite unknown. A coastguardsman, who had seen 

 them abroad, I forget where, declared them to be " pilot-fish/' a 

 diagnosis with which some of the fishermen, to whom the true pilot- 

 fish, Naucrates ductor, appeared to be known, could by no means 

 agree. It appears, however, that from a certain similarity of habits 

 the name is occasionally applied to the form before us, usually known 

 to British naturalists as the black-fish. 



I believe that about six or eight black-fish were brought ashore 

 on this occasion, of which, by the kindness of Mr. J. C. James of 

 Newlyn, I managed to secure four. They were all small specimens, 

 the total lengths being 13| inches, 13| inches, 12f inches, and 12f 

 inches. Before preserving them I examined the contents of their 

 stomachs, which consisted of a considerable number of young pollack, 

 about 3 inches long ; in fact, the stomachs were quite distended with 

 them. I also endeavoured to ascertain their sex, and concluded 

 that they were all immature males. Hermaphroditism has been 

 recorded by Syrski in this species (cf. Max Weber, U. Hermaph. b. 

 Fischen. Ned. Tijdsch., Jaarg. v, 1884, p. 37),* but it does not 

 appear whether this is a normal or abnormal condition. 



The colouration of the black-fish appears to be highly variable. 

 Couch draws special attention to this point, noting the difference 

 between Risso's description of Mediterranean specimens and the 

 condition in British examples that had come under the notice of 

 himself and earlier observers. That this, however, is not wholly 

 attributable to climatic influences, as Couch seems to have supposed, 

 may be inferred from an examination of Bonaparte's figure (Fauu, 

 * I am indebted to Prof. G. B. Howes for this reference. 



