. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. SALINITY AND ARTEMIA EXCYSTMENT RATE 199 the stock mixture of cysts and empty shells emerged (see method), all of the embryos which are presumed to have been viable emerged in all of the solutions. More than 96 per cent of the embryos that emerged from the shell also hatched from the membranous sac in 50-225 per cent sea water, inclusive, but in lower salinities this percentage decreased and no true hatching at all occurred in distilled water (Fig. 1). In distilled water the appendages of the emerged embryos did not mov
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. SALINITY AND ARTEMIA EXCYSTMENT RATE 199 the stock mixture of cysts and empty shells emerged (see method), all of the embryos which are presumed to have been viable emerged in all of the solutions. More than 96 per cent of the embryos that emerged from the shell also hatched from the membranous sac in 50-225 per cent sea water, inclusive, but in lower salinities this percentage decreased and no true hatching at all occurred in distilled water (Fig. 1). In distilled water the appendages of the emerged embryos did not move. The membranous sac disintegrated after several hours in about one-fifth of 225 200 175 k. I ISO 125 k •*w 100 PERCEA 75 50 25. O EMERGED 0 HATCHED 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 HOURS UNTIL 50 % EMERGED AND HATCHED FIG. 2. The rates of emerging and hatching in diluted and concentrated sea water at 25° C. One hundred per cent sea water corresponds to specific gravity , and 0 per cent sea water is distilled water (see Table I). The curves show the time lapse until 50 per cent of the embryos in populations emerge, and until 50 per cent hatch (see text). the cases, causing a sort of pseudo-hatching, but in these cases the nauplii always swelled, and often burst near the first joints of the large second antennae. Inactivity of the embryo probably interferes with hatching. Occasional cysts burst within 20-30 minutes after being placed in distilled water and aborted amorphous masses. This also oc- curred rarely in 12% per cent sea water and in higher salinities as well. The embryos that hatched throughout the range 12^4-225 per cent. 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 Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
