LARVAL AND POST-LARVAL FISHES— REGAN. 139 



and liave sudi a wide range that tlic definite assignment of lai'\ac to tlieii- species is 

 very ditticult. This difficulty is increased Ity the fact that llic head, owing to the 

 rehitively smaller size of the eye and mouth and the greater Icnglli of the snout, has a 

 physiognomy cjuite unlike that of the adult fish. However, by counting the myotomes 

 and fin-rays and taking into i-cmsideration the position of the tins, the .size of the 

 mouth, etc.. it is possible to make ileterminations which mav. in some cases, approximate 

 to the truth. 



The general character of the development has already been described in dealing 

 witli Mi/ctit]i]tuin autarcticnia. 



Myctopliuni hi'iioifi, Cocco (PI. \M. hgs. 1. 2). 



Several examples, from 4 to 7 mm. in total length, may belong to this species. 

 They have much in common with the larvae described and figured by Holt and Byrne 

 (Fisheries Ireland Sci. Invest. 1910, VI, p. 29, pi. I, fig. 8), from the Irish Atlantic 

 slope under the name " Scopelid larva, R 2." l)ut seem to be specifically distinct. They 

 are distinguished l)y their rather deep form, conical snout, strong teeth, and by 

 the distribution of the stellate pigment spots ; four large ones are present on each side, 

 i-espectively at the origin of the dorsal and anal fins, l)eh)W the adipose fin and above 

 the end of the anal fin ; usually there is a fifth on the side between the two last-named. 

 There is also a spot on the l)ack behind the head and a mid-ventral series of small spots 

 from the end of the lower jaw to the origin of the anal fin. I count 12 or 13 dor.sal 

 and 17 or 18 anal rays and 37 myotomes. 



South Atlantic. Station 311. 35° 29' S., 50" 2G' W. 2 metres. April 22nd, 1913. 



Myctiipltuiii hiteniKtuni, Uarm. (I'l. \'l, hg. 7). 



A specimen 8 mm. long is pi-obablv of this species. It is moderately elongate ; the 

 snout is short and the mouth is small, the maxillary extending to l)elow the middle of 

 the eye. The anal fin luis 14 rays and commences lielow the posterior part of the 

 dorsal, which has 11. The myotomes number 35. 



South Atlantic. Station 311. 35° 29' S., 50° 20' W. 2 metres. April 22nd, 1913. 



^[yctophum cocroi, Cocco. 



An example 20 mm. long has the characters of the adult fish, except that the eye 

 is relatively smaller, its diameter being less than the length of the snout. 

 Station 86. Off Three Kings Islands. 3 metres. July 25th. 1911. 



Dhtphus sp. (PL VI, figs. 3, 4). 



Form rather deep; snout obtuse and mouth obliijue. Length 4 to 5 nun. Dorsal 

 and anal fins eacli with about 14 rays; about 35 myotomes. Tlie disn-ibution of the 

 pigment is sho^^ii in the figures. 



Station 135. Spirits Bay, near North Cape, New Zealand. 3 metres. September 

 fst, 1911. 



