. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 198 A. J. GOLDFORB Jn Experiment 7\, for example, 2 to 6 tests were made at each age. An average of 173 eggs were examined after each test. Between ll/2 and 35 hours the time of centrifuging, required to produce the same percentage of equally zoned eggs, increased progressively from 2% to 51 o minutes (Fig. 4). When eggs were 27 hours old, it was necessary to centrifuge for 5'/L' minutes to zone 79 per cent (the initial per cent) to standard. When centrifuged for 3 minutes (the initial duration), only 1 per cent were zoned t
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 198 A. J. GOLDFORB Jn Experiment 7\, for example, 2 to 6 tests were made at each age. An average of 173 eggs were examined after each test. Between ll/2 and 35 hours the time of centrifuging, required to produce the same percentage of equally zoned eggs, increased progressively from 2% to 51 o minutes (Fig. 4). When eggs were 27 hours old, it was necessary to centrifuge for 5'/L' minutes to zone 79 per cent (the initial per cent) to standard. When centrifuged for 3 minutes (the initial duration), only 1 per cent were zoned to standard. This affords another measure of the increased viscosity at this age. After 35 hours there was rapid liquefaction. When 401/i> hours old, a sample centrifuged for 5'/L. minutes gave 100 per cent either en U •4-> 3 C — 5 bo c 'So I 4 53 U -a o .-. <s 87 v x 77 10 20 -SO 40 50 60 70 Hours FIG. 5. Another cx]HTimrnt as in Fig. 4, but for more ages. Same cyclical viscosity with a,m\ zoned to standard or over/.oned. Less centrifugation, , 4I-{ minutes, sufficed. When 43'^ hours old, eggs were centrifuged for 4\, 4, 3' 3, and 2 minutes respectively. All these gave 100 per cent zoned or overxoned egi;-. The lime required to zone to standard had de- creased from 5y2 to 1% minutes. In Experiment 7".,, Fig. 5, tests were made as in the previous ex- periment but over a longer series of ages. Viscosity increased pro- gre»ively during the first 40 hours. The increase was from 3 to 6^2 minute^ or 100 per cent, lietween 44 and 68 hours viscosity decreased rapidly. At late ages, even at the reduced time of centrifugation, nearly all the eggs were over/oned, so that liquefaction was greater than indicated by the 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 Biological L
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
