. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 182 R. K. ABRAMOWITZ AND A. A. ABRAMOWITZ with the twenty-first day for the segregated animals. We are not in a position to state the cause of this difference in the time relations of moult- ing in segregated and non-segregated animals, but we wish to point out that a sufficiently large group of animals has been used to demonstrate the accelerating effect of eyestalk removal on ecdysis. The percentages of moults (Fig. 1) were calculated on the basis of 70 animals, since 6 of the animals died before they had moulted. Only the
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 182 R. K. ABRAMOWITZ AND A. A. ABRAMOWITZ with the twenty-first day for the segregated animals. We are not in a position to state the cause of this difference in the time relations of moult- ing in segregated and non-segregated animals, but we wish to point out that a sufficiently large group of animals has been used to demonstrate the accelerating effect of eyestalk removal on ecdysis. The percentages of moults (Fig. 1) were calculated on the basis of 70 animals, since 6 of the animals died before they had moulted. Only the first moults were included in this curve. Three of the animals moulted twice during the experiment, the second moult occurring be- tween the twenty-first and twenty-sixth day after the first moult. Only 29 per cent of the control animals moulted during the 48 days, and none of these animals moulted a second time. Excluding the 3 cases in which •o 100 13 O 75 O - 50 O o> o> O c 25 o> O o> Controls 10 IS 20 30 35 48 Days Following Operation FIG. 1 moulting occurred twice, the degree of ecdysis in the operated group is about 300 per cent that of the control group over the same period of time. Furthermore, the onset of moulting in a mixed population chosen at random is two weeks earlier in the operated group than in the un- operated group. Finally, the loss of the eyestalks may shorten the inter- moult period. The inter-moult interval, of course, was not determined since none of the normal specimens moulted twice during the period of observation. However, a shorter inter-moult interval may result from eyestalk removal since 3 of the operated animals moulted twice (between 21-26 days following their first moult) during the 48 days. The un- operated moulted animals were carried for only 20-23 days after their first moult and consequently it is not possible to decide whether these animals might have moulted within a short time after the experiment. Please note that
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
