. Beginners zoology. Zoology. Fig. 226.— Artificial Fecundation. The egg-cells and sperm-cells are pressed out into a pan of water. paddle for sculling? An oar.'' State several reasons why the head of the fish must be very large, although the brain is very small. Does all the blood go to the gills just after leaving the heart.'' Make a list of the different species of fish found in the waters of your neigh- bourhood; in. the markets of your town. Reproduction.— The female fish deposits the unfertilized eggs, or ova, in a secluded spot on the bottom. Afterward the male fish deposits the sperms
. Beginners zoology. Zoology. Fig. 226.— Artificial Fecundation. The egg-cells and sperm-cells are pressed out into a pan of water. paddle for sculling? An oar.'' State several reasons why the head of the fish must be very large, although the brain is very small. Does all the blood go to the gills just after leaving the heart.'' Make a list of the different species of fish found in the waters of your neigh- bourhood; in. the markets of your town. Reproduction.— The female fish deposits the unfertilized eggs, or ova, in a secluded spot on the bottom. Afterward the male fish deposits the sperms in the same place (see Fig. 225). The eggs, thus unprotected, and newly hatched fish as well, are used for food by fish of the same and other species. To compensate for this great destruction, most fish lay (spawn) many thousands of eggs, very few of which reach maturity. Higher vertebrates (r.^. birds) have, by their superior in- telligence, risen above this wasteful method of reproduction. Some kinds of marine fish, notably cod, herring, and salmon, go many miles up fresh rivers to spawn. It is possible that this is because they were originally fresh-water species; yet they die if placed in fresh water except during the spawning season. They go. Fig. 227. —Newly hatched Trout, with yolk-sac adhering, eyes large, and fins mere folds o[ the skin. (Enlarged.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coleman, Walter M. Toronto : Macmillan
Size: 2503px × 999px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectzoology, bookyear1921
