. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REPRODUCTIVE CYCLE OF AMPHIURA CHIAJEI 269 25 u 20 o 0) Q. 6 0) 15. J FMAMJ J ASOND FIGURE 5. Presence of the Amphiura chiajei larvae in plankton hauls made at Station 1 (X) and Station 2 (•) ; X or • = 1 to 2 ophioplutei for 10 planktonic hauls; • • = 1 to 3 ophioplutei for 10 planktonic hauls; Continuous line curve: average temperature at 5 meters depth at Station 1 (January 1961-April 1964); Dotted line curve: average temperature at 5 meters depth at Station 2 (April 1961-April 1964). As I pointed out above, although I ha
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REPRODUCTIVE CYCLE OF AMPHIURA CHIAJEI 269 25 u 20 o 0) Q. 6 0) 15. J FMAMJ J ASOND FIGURE 5. Presence of the Amphiura chiajei larvae in plankton hauls made at Station 1 (X) and Station 2 (•) ; X or • = 1 to 2 ophioplutei for 10 planktonic hauls; • • = 1 to 3 ophioplutei for 10 planktonic hauls; Continuous line curve: average temperature at 5 meters depth at Station 1 (January 1961-April 1964); Dotted line curve: average temperature at 5 meters depth at Station 2 (April 1961-April 1964). As I pointed out above, although I have been able to observe the different stages of spermatogenesis, this is not true for oogenesis. In fact, no stage of maturation was disclosed in the numerous histological sections or smears which were exam- ined. The shedding stages begin suddenly after a long period of primary oocytes growth. Moreover, the attempts made for artificial fertilization in June and in September, were unsuccessful. There was no expulsion of polar globules after the addition of spermatozoa, as was observed in the asteroid Leptasterias hexactis (Chia, 1968) or when the oocytes were liberated in water, as in the case of Marthasterias glacialis. It is probable that maturation is accomplished very rapidly within the gonad, and is completed only a short time before the ejection of the eggs. This would explain why the secondary oocytes are absent in the histological sections which were examined. Therefore, there is not, as in the males, a more or less protracted period of sexual maturation. This characteristic seems to be frequent in Ophiuroides; it was observed also, after a histological ex- amination, in a Euryalae Gorgonocephalns caryi (Patent, 1969). Those in which. 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 Marine Bio
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
