500 SQUALID.E. 



length of the net, cutting out, as with shears, the fish and the 

 net that holds them, and swallowing both together." 



Mr. Couch has lately ascertained that the Blue Shark pro- 

 duces its young early in June. 



The specimen described measured fourteen inches ; the 

 head depressed, broadest between the eyes, which are lateral ; 

 half-way between the eyes and the point of the nose are the 

 nostrils, linear, directed obliquely downwards and backwards, 

 the most inferior portion covered with a valvular fold of skin ; 

 the eyes round and rather large ; the mouth forming half a 

 circle, the teeth in this specimen very minute, the cutting 

 teeth of the left side in the representation at the end belong 

 to this species, in each jaw of which there are three rows, 

 those immediately in the centre, to the number of four, being 

 calculated more for holding than cutting ; the number of rows 

 of teeth in the Sharks are said, and I believe correctly, to in- 

 crease with age, and vary in this species from one to six. 

 The branchial apertures are five, the fourth placed over the 

 line of the anterior edge of the pectoral fin ; the pectoral fins 

 large and falciform ; the body of the fish deepest in the line 

 of their origin, but becoming more compressed and tapering 

 from thence to the tail ; the first dorsal fin situated over the 

 space between the pectoral and anal fins, rather small, low 

 and rounded above, with a horizontal projecting elongation 

 at the base behind : the ventral fins small, obliquely truncat- 

 ed, and placed under the space between the first and second 

 dorsal fins ; the anal fin placed half-way between the ventral 

 fins and the lower lobe of the tail, opposed to or under the 

 second dorsal fin, and each ending in a prolongation directed 

 backwards ; the tail divided, the upper lobe two-thirds longer 

 than the lower, the vertebral column continued along it ; the 

 inferior lobe somewhat triangular in shape ; the upper lobe 

 falciform, and with an extension of the membrane towards the 

 extreme end. 



