Morphogenetic properties of the parts of the colony of Clytia johnstoni.
نویسنده
چکیده
r primordia of length 0-5-1-4 mm, (iii) stalks of open hydranths (polarized, the stolon grows out of the cut basal end). (b) Immediate differentiation of a polyp. Shown by (i) stalk primordia longer than 1-7 mm "' and some between 1-4 and 1-7 mm, (ii) bulbs greater than 0-28 mm diameter (i.e. had reached contractile stage), (iii) bulb primordia of all sizes having a 'stalk' longer than 0-35 mm; only the larger bulbs became polyps if the 'stalk' was shorter than 0-35 mm. (c) Immediate incipient differentiation (of a polyp ?) was shown by some stalk primordia of length 1-4-1-7 mm long. Partial hydranth differentiation (stomach and buccal region, no tentacles) was shown by an occasional isolated bulb. (d) Delayed stolon development. The time delay is variable but not random, with a marked tendency to start after 3-5 days and a less marked tendency after 9 days isolation. Shown by (i) all isolates which differentiated a polyp immediately on isolation, (ii) most bulb pri-
منابع مشابه
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ورودعنوان ژورنال:
- Journal of embryology and experimental morphology
دوره 30 3 شماره
صفحات -
تاریخ انتشار 1973