LOACH. 379 



body elongated, smooth, covered with a mucous secretion, 

 rounded in form before the dorsal fin, compressed behind 

 it : the dorsal fin commences half-way between the point of 

 the nose and the end of the fleshy portion of the tail ; the 

 ventral fins under the dorsal ; the anal fin commences half- 

 way between the origin of the ventral fin and the end of the 

 fleshy portion of the tail : the caudal rays slightly rounded. 

 The fin-rays in number are 



D. 9 : P. 12 : V. 7 : A. 6 : C. 19 : vertebrae 36. 



The head, body, and sides are clouded and spotted with 

 brown on a yellowish white ground ; the belly and under 

 surface white or yellowish white ; all the fins spotted with 

 dark brown, the dorsal fin and the tail the most so ; the 

 irides blue. 



I am indebted to the kindness of Mr. George Daniell 

 for the knowledge of two peculiarities in the structure of 

 the bones of the Loach, which are represented in the vig- 

 nette, and also for the use of a skeleton to draw and describe 

 from. 



Attached to each outer side of the first and second ver- 

 tebrse is a hollow sphere of bone of equal size, between 

 which, on the upper surface, the vertebrae are distinctly 

 seen ; but the union of the two spheres underneath hides the 

 vertebrae when looked towards from below. These circular 

 bones, which are hollow, and the smooth insides of which 

 can be seen through a horizontally elongated aperture that 

 exists on the outer side of each, these bones are analogous to 

 the scapulae, to their outer surfaces the bones of the proximal 

 extremity of the pectoral fins are articulated, and the fin 

 moved by powerful muscles, which assist in producing the 

 rapid motion observable in this little fish. Another pecu- 

 liarity existing in the upper surface of the head, is the want 



