. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 468 RELATIVE TIME UNITS 10 B. CASCAJALEN SIS O LIVE MATERIAL A 4 6 RELATIVE TIME UNITS 10 FIGURE 5. The dry weights of the embryo are plotted in a manner similar to Figure 1. The line is calculated from data represented by the circles. These represent embryos dis- sected out alive and dried immediately. The squares represent material preserved in formalin in 1878 and later transferred to the strong alcohol used in the Museum of Comparative Zoology, Cambridge, Mass. This varied between 75 and 90 per cent and was th
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 468 RELATIVE TIME UNITS 10 B. CASCAJALEN SIS O LIVE MATERIAL A 4 6 RELATIVE TIME UNITS 10 FIGURE 5. The dry weights of the embryo are plotted in a manner similar to Figure 1. The line is calculated from data represented by the circles. These represent embryos dis- sected out alive and dried immediately. The squares represent material preserved in formalin in 1878 and later transferred to the strong alcohol used in the Museum of Comparative Zoology, Cambridge, Mass. This varied between 75 and 90 per cent and was the sole preservative for specimens represented by the triangles. FIGURE 6. The dry weights of the embryo are again plotted as in Figure 1. The triangles represent material preserved originally in 10 per cent formalin and later kept in 70 per cent alcohol. When weighed .several months later there was excellent agreement with the values for living material studied at the time these were preserved. Most of the preserved material described has been handled in this manner. Two forms which could be distinguished by size, coloration, and mean weight of the embryos were taken from Gat tin Lake. The mean weight of the larger form is plotted in Figure 3 as mg. The smaller forms showed a very constant embryo weight averaging mg. Despite these differences, Hubbs (1942) was able to find no usual taxonomic character or measurement to justify considering the smaller form a separate species. Since the .sperm in these fishes are viable in the ovary for several months, the time required to reach any given stage of development cannot be determined even in laboratory specimens. Therefore, in this study the embryonic weights were ranked in order of stage of development (cf. Scrimshaw, 1944). Since the data show that there is no consistent dry weight change during development, no error was introduced in the tabulation of the raw data. However, the assumption for. Please note that these imag
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
