. Beginners' Zoology . Fig. 225. — The Stickleback. Instead of depositing the eggs onthe bottom, it makes a nest of water plants— the only fish that doesso — and bravely defends it. 120 BEGINNERS ZOOLOGY. Fig. 226.— Artificial Fecundation. Theegg-cells and sperm-cells are pressed out intoa pan of water. paddle for sculling TAn oar .^ State severalreasons why the headof the fish must large, although .the brain is very all the blood goto the gills just afterleaving the Make a list of thedifferent species offish found in thewaters of your neigh-bourhood; in the markets
. Beginners' Zoology . Fig. 225. — The Stickleback. Instead of depositing the eggs onthe bottom, it makes a nest of water plants— the only fish that doesso — and bravely defends it. 120 BEGINNERS ZOOLOGY. Fig. 226.— Artificial Fecundation. Theegg-cells and sperm-cells are pressed out intoa pan of water. paddle for sculling TAn oar .^ State severalreasons why the headof the fish must large, although .the brain is very all the blood goto the gills just afterleaving the Make a list of thedifferent species offish found in thewaters of your neigh-bourhood; in the markets of your town. Reproduction.— The female fish deposits the unfertilizedeggs, or ova, in a secluded spot on the bottom. Afterwardthe male fish deposits the sperms in the same place (seeFig. 225). The eggs, thus unprotected, and newly hatchedfish as well, are used for food by fish of the same and otherspecies. To compensate for this great destruction, mostfish lay (spawn) many thousands of eggs, very few ofwhich reach maturity. Higher vertebrates { birds) have,by their superior in-telligence, risen abovethis wasteful methodof reproduction. Somekinds of marine fish,notably cod, herring,and sal
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