COTTIDJ3. 349 



retreat of the Expedition from the coast. In writing out the 

 Natural History Report, after my return to England, I mis- 

 construed my brief record of the nasal spines, and by consider- 

 ing them to be similar to the cranial tubercles, made a ficti- 

 tious discrepancy with the characters of the common Coitus 

 quadricornis of the northern seas. On revisiting the same 

 coasts in 1849 I obtained more specimens and discovered my 

 error ; and, on a comparison of them with examples of the C. 

 quadricornis in the British Museum, I found that, except in 

 the greater size of the hexacornis and the more fully developed 

 cranial tubercles, the species was the same. In the fish of 

 Coronation Gulf the tubercles are not larger than those re- 

 presented in the portrait of an Iceland specimen published in 

 Gaimard's Atlas. 



COTTUS GLACIALIS (Richardson). 



Radii: Br. 6; D. 10/--17 ; C. 15; A. 14; V. 1/3; P. 17. 



PLATE XXIV., figs. 1, 2, 3, uat. size; fig. 4, magnified. 



Description. 



The general aspect of this species approaches that of Cottus 

 gobio of England, and is dissimilar to that of C. scorpio. Head 

 broad and rather depressed, with an obtuse snout : its length 

 is contained thrice and nearly a half in the total length of the 

 fish, while its breadth at the occiput rather exceeds its height 

 there. In profile, the back descends from the hind head 

 without any gibbous rising at the first dorsal, such as that 

 which characterizes C. porosus (C. et V. viii. p. 498). Body 

 tapering, and tail at the setting on of the caudal slender. 

 Armature : Nasal spines moderately large, pungent. Super- 

 orbital ridges elevated and even, including a smooth furrow 

 between them, and of their distal corners forming the anterior 

 pair of small cranial tubercles. Immediately behind these 

 tubercles rise another pair of ridges, scarcely so prominent, 

 bounding a less hollow space and terminating in the posterior 

 pair of still smaller tubercles. These four tubercles have little 



