. Zoology. Zoology. 60 ZOO LOOT. The young or larva has now both sides of the body alike. At this time two lobes arise from each side of the mouth. These separate from their attachment and form two dis- tinct hollow cavities, and by the time the larva attains what is called the BracUiolaria stage, the development of the body of the star-fish begins, for these two cavities subse- quently develop into two water-tubes. On one of these cavities the back of the star-fish is afterward developed, while on the other the under side with the feet or tentacles. m 5l\' Fig. GG.—Asterias vulgaris, natural
. Zoology. Zoology. 60 ZOO LOOT. The young or larva has now both sides of the body alike. At this time two lobes arise from each side of the mouth. These separate from their attachment and form two dis- tinct hollow cavities, and by the time the larva attains what is called the BracUiolaria stage, the development of the body of the star-fish begins, for these two cavities subse- quently develop into two water-tubes. On one of these cavities the back of the star-fish is afterward developed, while on the other the under side with the feet or tentacles. m 5l\' Fig. GG.—Asterias vulgaris, natural size. arise. The fully-grown larva is called a hracMolaria, as it was originally described with this name under the impres- sion that it was an adult animal. Fig. 68 shows the young star-fish growing in the posterior end of the larva or young, whose body it is now beginning to absorb; finally, the larva body disappears. At this time the star-fish is still minute, conical disk-shaped, with a crenulated edge. In this con- dition it remains probably two or three years before the arms lengthen and the adult form is 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 Packard, A. S. (Alpheus Spring), 1839-1905. N. Y. , Holt
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1897
