108 Dr. C. F. Liitken on the Changes of Form in Fishes 



Dussumieri) as the young of species which retain the spinous 

 character of the scales all their lives ; for they may just as 

 well belong to species which, like B. Raji^ become completely 

 smooth as they advance in age. The small Bramce with 

 spines, from 11-47 millims. long, that I have examined, which 

 in general agree with the young forms above mentioned and 

 formerly described, present no peculiarity which prevents our 

 referring them to B. Raji ; and consequently we may very 

 well provisionally range these nominal species among the 

 synonyms of the type species in question. It is probable, 

 however, that the young individuals belonging to the different 

 species of Brama will closely resemble one another, and be 

 extremely difficult to distinguish ; in those which I have at 

 my disposal, some of which (the largest) were found in the 

 stomach of large voracious fishes, and others (the smaller ones) 

 fished at the surface of the Atlantic, I have been able to 

 recognize only the elements of a single continuous series, and 

 not the representatives of several species. One of the oldest 

 and one of the youngest individuals of this series referred to 

 B. Raji are represented in pi. iv. (of the Danish memoir) ; 

 and I refer the reader for their differences and for their com- 

 parison with the adult fish to figs. 1 and 2. 



"With the young Bramce which we have just been discussing 

 there was also a Pterycomhus^ perhaps a young P. hrama^ an 

 arctic species inhabiting deep water, hitherto known only 

 from specimens derived from the coasts of Finmark and Nor- 

 way ; this specific determination, if correct, will furnish a 

 fresh proof of the conformity presented in general by the 

 faunas of great depths in the tropical and arctic seas. In the 

 stomach of the same albacore which contained these inter- 

 esting young Bramidse there was also a young fish belonging 

 to the arctic genus Himantolophus^ perhaps H. Reinhardti. 

 Fig. 4, pi. iv. (of the Danish memoir) , placed near that of the 

 adult Brama^ will elucidate the very considerable changes 

 that the young Pterycombi undergo during their growth and 

 development. 



~") A pelagic genus allied to Brama and Pterycomhus is the 

 genus Pteraclis, the still little-known species of which per- 

 haps need to undergo some reduction. Our sailors have also 

 found it in the stomachs of albacores ; and they have moreover 

 captured in the nets very small examples of 7-15 millims. long. 

 Their physiognomy greatly resembles that of the young 

 Bramce and Pterycombi ; and they differ as much as these and 

 the young dorados from fully developed fish. The body is 

 short, thick, and pyriform ; the scales are high and hexagonal, 

 each armed with a spine directed backward ; the praeoper- 



