350 COTTIDjE. 



prominence, being much enveloped in the skin, and are nei- 

 ther rough nor spinous : their plan is represented in Plate II. 

 fig. 2. 



Preoperculum emitting the principal spine from the point 

 where it is supported hy the smooth rib of the second subor- 

 bitar. This spine is subulate and acute, rises above the axis 

 of the fish at an angle of 45, and does not reach to the edge 

 of the gill-cover : from its base a shorter spine inclines slightly 

 below the axis, and the proximal end of the preoperculum 

 tapers so as to form a third small and bluntish spine, which 

 stands just behind the angle of the lower jaw and has an in- 

 clination forwards and downwards; it is enveloped in loose 

 integument. There are no other prominent points on the pre- 

 operculum. The bony operculurn consists of a horizontal 

 narrow piece or rib that tapers into a spine, whose point does 

 not attain the membranous edge of the gill-cover, and of a 

 slender descending limb, which joins a corresponding process 

 of the suboperculum splintwise. Between the disc of the sub- 

 operculum and the main limb of the operculum there is a tri- 

 angular fleshy space, and just behind the inferior preopercular 

 spine the suboperculum emits a small pungent spine, directed 

 downwards.* A moderate-sized suprascapular spine lies pa- 

 rallel to the opercular one and immediately over it, complet- 

 ing the armature of the head. 



The fins are rather large ; their position may be ascertained 

 by referring to fig. 1, wherein they are represented fully ex- 

 tended. All the rays of the anal and second dorsal are jointed. 

 Anus placed under the third ray of the second dorsal. 



Lateral line constructed, as in C. porosus, of a series of 

 short cutaneous tubes, elevated above the skin, open at the 



* M. Valenciennes describes a spine as occupying nearly this posi- 

 tion in C. porosus, but as belonging to the operculum. " L'opercule 

 donne, conrnie a I'ordiuaire, une epine de son angle superieur ; elle est 

 courte et ne depasse pas le bord membraneux ; mais il en donne une 

 autre tres-pointue, de son angle inferieur pros de sous-opercule." C. 

 ot V. viii. p. 499. 



