AGONID.E. LXXI V. 151 



depth 6. D. VII -18. A. 15. V. I, 3. L. 3. Deep waters of 

 L. Michigan and L. Ontario. (To Rev. Zadock Thompson, author 

 of Nat. Hist, of Vermont.) 



191. TRIGLOPS Reinhardt. (rpiyXa, Trigla ; oty, appearance.) 



419. T. pingeli Reinhardt. Head slender; eye large; tail very 

 slender ; preopercular spines small, simple ; sides with peculiar 

 scales and prickles. Olivaceous, variegated with darker; sides 

 spotted with dark ; a black ocellus on spinous D. Head 3^ ; depth 

 about 5. D. IX -21. A. 21. L. 5. Arctic seas, S.to Cape Cod. 



192. GYMNACANTHUS Swainson. (yv^vos, naked ; 

 aicavQa, spine.) 



420. G. tricuspis (Reinhardt). Eye very large; skin mostly 

 smooth ; preopercular spine broad, shorter than eye, with 3 

 points ; V. very long. Dark brown with darker bars ; axils dusky 

 in < with round white spots. Head 3; depth 4f. D. XII -16. 

 A. 18. V. I, 3. L. 12. Arctic, S. to Me. (Eu.) (Lat., tris, 

 three ; cuspis, cusp.) 



FAMILY LXXIV. AGONIDJE. (THE ALLIGATOR-FISHES.) 



Fishes allied to the Cottidce and similar in general structure, but 

 with the body completely covered by a coat of mail composed of 

 about eight series of large bony plates ; head entirely bony exter- 

 nally ; suborbital stay covering the cheek ; gills 3, no slit behind 

 the last, pseudobranchise large. Vertebrae (as in other Arctic 

 fishes) numerous, 35 to 40. Spinous dorsal sometimes wanting. 

 Small fishes, chiefly of the Arctic seas; genera 10, species about 

 20. (a, privative; ycow'a, joint; i. e., rigid.) 



a. Spinous dorsal obsolete ; gill membranes free from isthmus. (Aspidopho- 



roidince.) 

 b. Bony plates keeled, without spines; fins very small; teeth on vomer. 



ASPIUOPHOROIDES, 193. 



193. ASPIDOPHOROIDES Lacdpede. (acnrts, shield ; <opo, 



to bear ; tl8os, form.) 

 a. Snout with two large diverging spines above ; no other spines present. 



421. A. monopterygius (Bloch). Body elongate, subterete, re- 

 sembling that of a pipe-fish ; eyes very large. Brownish, obscurely 

 banded. Head 5f; depth 9. D. 5. A. 6. Lat. 1. 50. L. 6. Cape 

 Cod, N. (/ioj/off, single ; irrepvg, fin.) 



FAMILY LXXV. CEPHALACANTHID^El. 

 (THE FLYING GURNARDS.) 



Body elongate, with bony keeled scales ; head blunt, cuboid, its 

 surface almost entirely bony ; nuchal shield with a strong spine on 



