722 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY IV. 



base of the pectorals, the membranes below completely united to the 

 shoulder girdle and isthmus; apparently no slit behind last gill; a 

 stout, straight, preopercular spine; nasal spines present; no other 

 spines on head. Skin everywhere on head and body iirm, immovable, 

 densely covered with stiff bifid or trifid spinous prickles; spinous dor- 

 sal very small; pectoral with procnrrent base, {pa/xi/'og, snout; zorrw?, 

 Cottus.) 



IIOS. R. ricliardsoni Gthr. 



Brownish, with G or 8 obliqne black bands running downward and 

 forward; a white bar below eye; a dusky bar at bases of pectorals and 

 ventrals, the tins otherwise plain. Head hard and bony, nearly as 

 long as rest of body; snout rather longer than eye, which is of mod- 

 erate size, and with partly vertical range; maxillary extending to front 

 of eye; suborbital stay strong; pectorals long, reaching tips of ventrals 

 and past front of anal; ventrals long, their rays prickly. Head 2; 

 depth 2. D. VII-14; A. 7 or 8; V. ca. I, 4. L. 2^ inches. Northern 

 seas. Three specimens known : the one here described from Bering's 

 Straits; the original, said to be from "Fort E-upert"; a third recently 

 obtained by Mr. Lockington, from the stomach of a Sebastodes, at Mon- 

 terey. 



(Guuther, Ann. Mag. Nat. Hist, xiv, 370, 1874; Bean, Proc. U. S. Nat. Mus. 1881, 

 252.) 



Family CVIII («) — AGONID^.* 



{The Allifjator-Jishes.) 



Body elongate, or more or less elevated, angular, covered with about 

 eight longitudinal series of large bony plates, which form a coat of mail ; 



*Tlie following genera and species of this type have been described from Kam- 

 tscliatka and the Kurile Islands, and will doubtless be found on our Alaskan coast: 



HYPSAGONUS Gill. 



(Gill, Proc. U. S. Nat. Mus. 1861, 259: type Aspidopliorus quadricornis Cnv. & Val.) 

 • Body compressed and elevated, its depth greater than length of head, more than 

 one-third the body; head small, separated from the base of the dorsal by a very deep 

 nuchal depression; top of head very uneven; mouth terminal, the jaws about equal; 

 no vomerine teeth ; gill-membranes undescribed, jirobably free from isthmus ; no bar- 

 bels; scales large, not very rough, most of them striate and armed with a central 

 spine or tubercle; dorsal spines strong, the first serrated; pectorals short, ijrocurrent; 

 ventrals small, (u^z, high; Agonus.) 



H. quadricornis (Cuv. & Val.) Gill. 

 Two horns above eye and 2 above occiput; iuterorbital space nearly as broad as 



