. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VOLUME CHANGES OF AMPHIBIAN EGGS 465 more hypotonic solutions and also the survival rate was higher (cf. Holtfreter, 1943). The data in the next section confirm these observations. Hyla—fertilised eggs ivitlwut jelly In the last series of these preliminary studies, fertilized eggs of Hyla with the jelly removed were used. The data obtained from a single experiment are pre- sented in Figure 5. The eggs were measured 20 minutes to an hour and a quarter after having been placed in the solutions, after 18-19 hours and again afte
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VOLUME CHANGES OF AMPHIBIAN EGGS 465 more hypotonic solutions and also the survival rate was higher (cf. Holtfreter, 1943). The data in the next section confirm these observations. Hyla—fertilised eggs ivitlwut jelly In the last series of these preliminary studies, fertilized eggs of Hyla with the jelly removed were used. The data obtained from a single experiment are pre- sented in Figure 5. The eggs were measured 20 minutes to an hour and a quarter after having been placed in the solutions, after 18-19 hours and again after 48 hours. The first two series of measurements were essentially the same but after 48 hours the volume changes in the two most hypotonic solutions were much IJ&1 LJ O > °/n NA CL 0. 0 FIGURE 5. Volume changes of fertilized Hyla eggs (with jelly removed) when placed in solutions of NaCl of different concentrations. O, measurements made after %-l-/4 hours; • , after 18-19 hours; A, after 48 hours. larger than after shorter exposures to these solutions. These eggs, like those with jelly, changed volumes as if they were osmometers with a large percentage of their volume osmotically inactive. At the end of 4 days all of these eggs in , in and in NaCl were dead. In NaCl 14% of the eggs were dead after 4 days and 36% after 5 days. After 5 days in water, triply distilled from glass, all of the eggs were living. In another series of observations after 4 days all of the eggs had died in NaCl; 64% in Nacl, 18% in NaCl and all were living in water. DISCUSSION The present series of experiments was an initial preliminary survey to deter- mine whether or not the eggs of Bufo and Hyla would change volumes in solu- tions of different osmotic pressures. Having shown that this is the case, these changes will subsequently be studied in more detail. Consequently, it is advisable to limit our discussion of the
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
