We have examined the localization of the cells containing sedi_mented amyloplasts (putative statocytes) and its relation to the graviresponding sites in the shoots of normal and lazy rice seedlings. All graviresponsive organs of the shoots of normal rice seedlings, the mesocotyl, the coleoptile and the leaf-sheath base, were found to possess the statocytes. This is the first indication that mesocotyl senses gravity by its own cells in inducing gravitropic bending in rice seedlings. In lazy-Kamenoo, although the shoots lost their gravitropic response with the advance of age, sedimentation of amylo_plasts itself might not be attributable to the agravitropic growth of the shoots, because, including those of the leaf-sheath bases that had lost their response to gravity, sedimented amyloplasts appeared to be identical to those of nor_mal Kamenoo and of younger seedlings of lazy-Kamenoo whose gravitropism is still apparent.

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Sustained release formulation of hCG, hCG minipellet, was applied to induce oviposition of newt. Period of egg spawning was prolonged with a certain delay of its initiation. When hCG minipellet was injected to newt that was hibernating, it induced egg spawning even after one month of hibernation. Results suggest that minipellet keeps steady concentration of hCG at the effective level for longer period. For the study on early development of newt egg, it is essential to obtain egg on orbit. hCG minipellet makes it possible even at launch slip or early “late access”.

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