COTTlDjE. 355 



membrane of the eyes, but the space between the orbits is 

 as usual concave. The postorbital tubercle on each side is 

 small but conspicuous, and the occipital pair also exist, though 

 they are not so isolated from the surrounding parts. All the 

 four are finely furrowed, and through a lens appear cancellated, 

 but are scarcely rough to the touch. The ridges connecting 

 these tubercles are low, and enclose a slightly concave space, 

 which, with the ridges themselves, is thickly covered by sca- 

 brous bony plates. Similar plates of different sizes exist on 

 the gill-covers, temples, nape, and fore-part of the back, as 

 represented in figure 2 : there is also a row of smaller ones 

 between the second dorsal and lateral line. The belly is soft 

 and smooth throughout. 



The lateral line is composed of a series of short, soft, raised 

 tubes, and runs along the upper third of the back until it 

 comes opposite to the last rays of the second dorsal and anal, 

 when it makes a short deflection, and is continued through 

 the middle of the remainder of the tail. 



Fins in general large. The pectoral has much spread, an 

 obliquely oval form when expanded, and reaches over the an- 

 terior third of the anal. From the seventh downwards the 

 rays shorten rapidly, the lowest one having oidy about a sixth 

 of the length of the longest ones. The first dorsal, commenc- 

 ing over the middle of the operculum, has its last ray over the 

 anus : a short space divides it from the second dorsal, which is 

 slightly higher, and has no spinous ray. The anal is also des- 

 titute of a spine, has shorter rays than the second dorsal, and 

 goes a little nearer to the caudal. The spread of the caudal, 

 as in the Cotti, is not great, though its rays are tolerably long. 

 Three longish unbranched but jointed rays, and a spine of half 

 their length, constitute the ventrals, whose tips go a little past 

 the anus. 



The lively colours of the recent fish have perished in the 

 specimen after two years' maceration in spirits. The under 

 surfaces of the head, body, and tail, are milk-white. We are 

 indebted for the specimen to Dr. Rae, who caught it in the 

 northern part of Hudson's Bay. 



