GEN. SELACHUS. BASKING SHARK. 311 



the article above referred to, contends for their dis- 

 tinction, founding his opinion on the examination of 

 specimens. 



Gen. CXI. Selachus. — Of this genus, the distinc- 

 tive characters of which v^ill be found in the Synop- 

 sis, we have but one species, namely, 



(Sp. 226.) C. maximus. The Basking Shark, 

 by far the largest of our native fishes, frequently 

 measuring upwards of thirty feet. Several of its 

 characters are very strongly marked. The teeth 

 are conic, simple, and rather small for so large a fish. 

 The under lobe of the tail is not much smaller than 

 the upper, which makes the caudal appear nearly 

 regularly lunate. The branchial apertures are very 

 large, and almost encircle the neck. The tail and 

 fins generally are rather small, but this does not 

 prevent it swimming with considerable velocity 

 when occasion requires. Usually, however, it ig 

 not much given to locomotion, delighting either to 

 move slowly along the surface with the dorsal fin 

 above water, or even to repose in perfect stillness, 

 commonly with the back, but at times with the 

 belly uppermost, as if enjoying the light and warmth. 

 It is this habit which has led to it being called by 

 some, the Sun- fish, and by Pennant the Basking 

 Shark, a name now generally adopted. It is likewise 

 named the Sail- fish. " They will permit a boat to 

 follow them, without accelerating their motion, till 

 it comes almost within contact, when a harpooner 

 strikes his weapon into them as near to the gills as 

 possible ; but they are often so insensible, as not to 



