270 CETACEA 



Grampus. 1 — Teeth none in the upper jaw ; in the mandible few 

 (3 to 7 on each side), and confined to the region of the symphysis. 

 Vertebra?: C 7, D12, L 19, C 30 ; total 68. General external 

 characters much as in Globicephalus, but the fore part of the head 

 less rounded, and the pectoral fin less elongated. 



But one species, G. griseus, is certainly known, about 13 feet 

 long, and remarkable for its great variability of colour. It has 

 been found, though rarely, in the North Atlantic and Mediterranean. 

 A skull from the Cape of Good Hope, which differs slightly from 

 that of the above, has been described under the name of G. richard- 

 soni. 



Fcresia. 2 — This genus, known at present only by two skulls, 

 may be provisionally placed here. These appear to indicate a form 

 connecting Globicephalus, Grampus, and Lagenorhynchus. From the 

 latter they differ chiefly in the smaller number (about ^-f) and much 

 larger size (6-7 mm. in diameter at base of crown) of the teeth. 



Lagenorhynchus. 3 — Rostrum scarcely exceeding the length of the 

 cranium, broad at the base and gradually tapering towards the 

 apex, depressed. Pterygoids normal, meeting in the middle line. 

 Teeth small (not exceeding 4 mm. in diameter), ff to f f . Vertebrae 

 very numerous, 80 to 90. Spines and transverse processes of the 

 lumbar vertebrae very long and slender ; centra short. Externally, 

 head with a short but not very distinct beak. Two species, 

 L. albirostris and L. acutus, are occasionally captured on the British 

 coasts. Other species occur elsewhere. 



Group B. — Head with distinctly elongated rostrum, or beak, 

 generally marked off from the prenarial adipose elevation by a V- 

 shaped groove. Rostrum of skull considerably longer than the 

 cranial portion. Atlas and axis firmly united ; all the other cervical 

 vertebrae free. 



Tf we add to it the above-mentioned genus, Lagemrhywihus, this 

 group will include all the true Dolphins, Bottle-noses, or, as they 

 are more commonly called by seafaring people, "Porpoises," which 

 are found in considerable abundance in all seas, some species being 

 habitually inhabitants of large rivers, as the Amazon. They are all 

 among the smaller members of the order, none exceeding 10 feet in 



length. Their food is chiefly fish, for the capture of which their 

 long narrow beaks, armed with numerous sharp-pointed teeth, are 

 well adapted, but some appear also to devour crustaceans and 

 molluscs. They are mostly gregarious, and the agility and grace 

 of their movements in the water are constant themes of admiration 

 to the spectators of the scene when a " school of Porpoises " is 

 observed playing round the boWs of a vessel at sea. 



1 Gray, Zoology of Erebus and Terror, p. 30 (1846). 



- Gray, Proc. Zool. Soc. 1870, p. 77. 

 3 Gray, Zoology of Erebus and Terror, \>. 35 (1846). 



