380 SQUALID.E. 



snout to the pectoral fins, and thick even to the tail, which 

 organ from the root was five feet and a half long, and conse- 

 quently more than half the length of the body ; eye promi- 

 nent, round, hard, four inches from the snout ; iris blue, 

 pupil green : the nostrils small, and not lobed ; mouth five 

 inches wide, shaped like an horse-shoe ; teeth flat, triangular, 

 in two or three rows, not numerous ; spiracles five ; pectoral 

 fins wide at the base, pointed, eighteen inches and a half 

 long. Measured along the curve, from the snout to the first 

 dorsal fin, was two feet five inches, the fin triangular ; from 

 the first dorsal to the second, fourteen inches and a half; this 

 and the anal fin small ; ventral fins also rather small, triangu- 

 lar ; above and below at the base of the tail a deep depres- 

 sion ; skin smooth ; lateral line central and straight ; breadth 

 of the tail, including both lobes, thirteen inches ; the upper 

 lobe narrow throughout its great length, and on the lower 

 margin, at four inches from the extremity, is a triangular 

 process. Colour of the body and fins dark blue, mottled 

 with white over the belly." 



Mr. Couch says it is not uncommon for a Thresher to 

 approach an herd of Dolphins (Delphini) that may be sport- 

 ing in unsuspicious security, and by one splash of its tail on 

 the water put them all to flight like so many hares before a 

 hound. 



" The specimen here described was taken at the entrance 

 of the harbour of Looe in Cornwall, in October 1826, hav- 

 ing become entangled in a net set for Salmon. The mouth 

 seemed more feeble than in most of its genus, which 

 is rendered more probable by the circumstances of its cap- 

 ture ; for the Blue Shark (next to be described) would in an 

 instant have cut its way through an obstruction that proved 

 fatal to the Thresher. The stomach was filled with young 

 Herrings." 



