504 FISHES CHAP. XVIII 
— 
higher, for the purpose of spawning, each female being attended 
by from one to four males.‘ During brief recurring periods of 
excitement, accompanied by convulsive lashing movements, the 
eges and sperm are emitted. The eggs are extremely sticky, and 
adhere tenaciously to the rocks and stones on which they are 
deposited. In a few days the embryos hatch out, and at this 
stage the larva has a huge mouth surmounted by a terminal 
preoral disc, fringed with a row of marginal wart-like suckers 
(Fig. 300). The yolk sac is so large as greatly to hamper the 
movements of the larva ; hence, by means of its suckers, the young 
Lepidosteus attaches itself to surrounding objects, and remains 
pt-f. 
NN 
Fie. 300.—Larval Lepidosteus osseus, 11 mm. long. «@, Anus; a./, c.f, d.f, developing 
anal, caudal, and dorsal fins; m, mouth; ol, olfactory organ; op, operculum ; 
pt.f, pectoral fin; s, sucker. (From Balfour and N. Parker.) 
almost entirely motionless for some little time after hatching. 
Later, about a fortnight after escaping from the egg, the yolk 
becomes completely absorbed, the suckers degenerate and eventually 
disappear, and the larva, freed from its load of nutritive reserve, 
assumes a more active life. . After the absorption of the yolk the 
larvae of Mosquitos appears to form the exclusive diet of the 
young Lepidosteus for some time, but very soon young Fishes are 
readily devoured.” | 
Lepidosteus seems to have been abundant in Europe during 
the Eocene and Miocene periods, but became extinct before the 
Pliocene. In North America, also, the genus dates from the 
Eocene, and still survives. 
Order IV. Teleostei. 
[For the account of this Order, see pp. 541 f.] 
1 Alex. Agassiz, Proc. Amer. Acad. Arts and Se. xiii. 1878, p. 65; Mark, Bull. 
Mus. Comp. Zool. Harvard, xix. 1890, p. 1. 
2 Mark, op. cit. p. 8. 
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