342 BTJLLETIISr OF THE BUREAU OF FISHERIES 



22 fathoms deep. Young ones have been found living within the shells of the 

 giant scallop {Pecten magellanicus) , a curious habit they share with the striped snail 

 (p. 344), and with the hakes of the genus Urophycis (p. 449). Little is known of the 

 life of this sea snail in the Gulf of Maine except that it is supposed to work inshore in 

 winter to breed but usually keeps at some little depth in summer. Presumably it 

 feeds chiefly on small crustaceans and small shellfish like its European relative. 



Breeding Jiahits. — The spawning of tlie American sea snail has not been observed. 

 In North Sea waters the spawning season of the European N. montagui endures 

 from February until April, rarely until July. Sea snails must spawn at least from 

 March to midsummer in the Gulf of Maine, for Huntsman has found the larvse in 

 Passamaquoddy Bay as early as April while we towed one only 7 mm. long on 

 German Bank as late as September 2, 1915. The eggs of the European fish, which 

 are about 1.1 mm. in diameter, pale straw color to light salmon pink, sink and 

 stick together in little clusters that adhere to hydroids, seaweeds, sticks, or debris 

 of any kind. These clusters are often brought up on trawl lines from 4 to 30 

 fathoms and are sometimes found close up to tide mark. There is no reason to 

 suppose that the males care for the eggs, and the latter are so hardy that they do 

 not suffer even from exposure to the air for hours. Judging from the dates when 

 newly hatched larvss have been seen, incubation of the European species occupies 

 a month — perhaps longer in the case of the eggs spa-RTied earliest and at winter 

 temperatures. The larvaj of the European N. montagui are about 3.3 to 4.5 mm. 

 in length at hatching, with small rose red yolk sac containing a large oU globule and 

 inclosed in a net of blood vessels. The yolk is absorbed in about 14 days when the 

 larva is about 3.9 to 4.2 mm. long, and with further growth the body, which is at 

 first elongate, becomes deeper and the head larger. The fin rays appear and the 

 sucker is formed at about 7 to 8 mm., and most of the characters of the adult are 

 apparent at 11 to 12 mm. length. Throughout the larval stage the pectoral fins 

 are brilliantly pigmented with yellow and black.' 



Commercial importance. — This little fish is of no importance either to the pro- 

 fessional fisherman or to sportsmen, but it plays a role in the economy of the sea 

 as food for larger fish, fry of its European relative having been found in cod stomachs. 



130. Striped sea snail (Liparis liparis Cuvier) 



Sea snail 



Jordan and Evermann, 1896-1900, p. 2116. 



Description. — This little fish closely resembles the sea snail (p. 340), especially 

 in its tadpolelike form, in the presence of a sucking disk in which the rays of the 

 ventrals (reduced to mere knobs) serve as a central support, and in the peculiar 

 outline of the pectorals with their secondary frilled basal lobes. The most obvious 

 difference between the two species is that there is no separation between the spiny 

 and the soft parts of the dorsal fin of the striped sea snail. Furthermore there are 



' Mcintosh and Mastermann (The Life-Histories of the British Marine Food-Fishes, 1897) and Ehrenbaum (Nordisches 

 Plankton, Band I, 1905-1909) both give good descriptions of the larvse of the European species from which the preceding is con- 

 densed. 



