. Annual report of the Regents. New York State Museum; Science. Fig. 31. A fully developed statoblast, frond and side view (after Allman) . " When exposed to conditions favorable to its development, the two faces after a longer or shorter period separate from one another and a young polyzoan gradually emerges and floats away freely through the surrounding water. The surface of the young polyzoan thus become free is destitute of cilia except on the tentacles, and the motions of the young animal seem to be quite passive, except as they may be influenced by the cilia on the tentacles. At the
. Annual report of the Regents. New York State Museum; Science. Fig. 31. A fully developed statoblast, frond and side view (after Allman) . " When exposed to conditions favorable to its development, the two faces after a longer or shorter period separate from one another and a young polyzoan gradually emerges and floats away freely through the surrounding water. The surface of the young polyzoan thus become free is destitute of cilia except on the tentacles, and the motions of the young animal seem to be quite passive, except as they may be influenced by the cilia on the tentacles. At the period of its escape it possesses all the essential organization of the adult. The retractor muscles are well developed and the polypid is capable of regular exsertion and contraction, but the ectocyst is colorless and transparent and free from the earthy particles which in the greater number of species are afterward formed in it, and the little animal is still simple. It loses no time, however, in developing gemmae, which soon change it to the compound form of the adult. " The general structure of the statoblasts being now under- stood, the important question at once suggests itself. What is the true importance of these bodies ? All that we have seen of them is manifestly in accordance with the nature of a bud. The invariable absence of a germinal vesicle and germinal spot, and their never exhibiting the phenomena of yelk cleavage, inde- pendently of the conclusive fact, that true ova and ovary occur elsewhere in the same individual, are quite decisive against their being eggs. We must then look upon them as gemmce peculiarly encysted and destined to remain for a period in a quiescent or pupa-like state. It was for this reason, therefore, that I pro- posed for them the name of statoblasts — Izaro- jSMffry].^^. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these i
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