FISHING FROG. 



307 



cording to M. Bailly, to twenty-two. The figure on the 

 left side of the vignette beneath shows the manner in which 

 these two elongated appendages are attached, as well as the 

 freedom of action of which, by the action of various muscles, 

 they are capable. The first is articulated by a process 

 resembling two links of a chain, by which almost universal 

 motion is obtained ; the second is more limited, and 

 appears, except as far as flexibility may assist it, to be only 

 capable of being brought forward or backward.* 



These elongated shafts are formed of bone covered by 

 the common skin ; and as the soft parts are abundantly 

 supplied with nerves, they may also serve the Angler as 

 delicate organs of touch. The uses to which they are ap- 

 plied are singular. While couching close to the ground, 

 the fish, by the action of its ventral and pectoral fins, stirs 

 up the sand or mud : hidden by the obscurity thus produced, 

 it elevates these appendages, moves them in various direc- 



* The three-part figure on the right hand of the vignette above represents 

 the heart of the Angler, from the Transactions of the Royal Society. The 

 lower portion is the auricle, before entering which the large veins unite. The 

 auricle opens into the side of the middle portion, which is the ventricle. The 

 upper part is the branchial artery, dilated, forming the bulbus arteriosus. Above 

 the bulb the branchial artery divides to form three, and further division takes 

 place before passing to the branchial arches. 



