674 ritOF. It. COLLETT OX k NEW AGONOID FISH. [Xov. 20, 



Locality. — Kamtschatka. In 1879 the museum of Christiania 

 received from Consul Henry Lund in San Francisco a small 

 collection of fishes and marine invertebrates, collected by a 

 Norwegian sailor at Kamtschatka. Amongst the first were 12 

 specimens of this species, some of which were rather defective and 

 in a bad state of preservation. All except one were full-grown 

 specimens. The exact locality was not given. 



Eemabks. — A. gilberti is allied to A. (Podothecus) acipenserinus, 

 Tiles. 1810, but differs from that species in several characters, 

 viz. : — 



The more elongated body. In A. gilberti the end of the 2nd 

 dorsal is midway between the caudal and the middle of 1st dorsal ; 

 in A. acipenserinus between the caudal and the beginning of the 

 1st dorsal. 



The more compressed body. From head to caudal everywhere 

 higher than broad ; in A. acipenserinus much broader than high. 



The longer snout. The interorbital space is contained 3 times 

 in the length of the snout ; in A. acipenserinus a little more than 

 twice. 



Dorsals more separated ; interdorsal space with 3 or 4 plates, 

 in A. acipenserinus only 1 plate (sometimes 2), or the fins almost 

 contiguous. 



Ventral groove present in A. gilberti, absent in A. acipenserinus. 

 Colour with distinct stripes on head and spots on body ; in A. 

 acipenserinus cross-bars on the body, the head being almost 

 unspotted. 



The other species of the same subgenus, A. {Podothecus) valgus, 

 Jord. and Gilb. 1880, has the body everywhere broader than high. 

 The spines of the head are more numerous (more than 70 spines 

 and tubercles on the head) ; there is a deep quadrangular pit on 

 the occiput ; no barbels on lower side of snout ; the 1st dorsal 

 commences behind the seventh dorsal plate, and the fin-formula is 

 different. 



The genus Podothecus was established by Grill in 1861 ! for a 

 species called P. pcristethus, which is commonly believed to have 

 been based on a badly-preserved specimen of A. acipenserinus. 

 But it must be borne in mind that one of the characters of the said 

 genus (the very one from which the name is derived), " ventral fins 

 received in a long lanceolate groove," is not shown by A. acipen- 

 serinus. 



As other essential characters of the genus are mentioned " the 

 longer spinous dorsal and the greater number of plates on the 

 breast." 2 Xone of these characters, however, are of sufficient 

 importance to justify the establishment of a new genus. 



As another character for Podothecus, Jordan and Gilbert state 3 



1 Proc. Acad. Nat. Sci. Philad. 1861, p. 258. 

 a Proc. U.S. Nat. Mu 3 . vol. iii. 1880, p. 332. 



3 " Synopsis of the Fishes of North America" (Bull. U.S. Nat. Mus. no. 16, 

 p. 714, Wash. 1882). 



