. The Biological bulletin. Biology; Zoology; Marine biology. ENDOCRINES AND CRAYFISH GROWTH 257 ing molt would indicate that the synthetic activities of these cells had ceased. It is during this time that many active growth processes occur. Discussion So far we have seen that major changes occur in the two endocrine organs, x organ and y organ, at the time the animal molts. The secretory activity of the x organ neurosecretory cells, as indicated by type 2 cell counts, is compared to growth of regenerating limbs in Figure 8. The figure represents a generalization of the data, and an explanation
. The Biological bulletin. Biology; Zoology; Marine biology. ENDOCRINES AND CRAYFISH GROWTH 257 ing molt would indicate that the synthetic activities of these cells had ceased. It is during this time that many active growth processes occur. Discussion So far we have seen that major changes occur in the two endocrine organs, x organ and y organ, at the time the animal molts. The secretory activity of the x organ neurosecretory cells, as indicated by type 2 cell counts, is compared to growth of regenerating limbs in Figure 8. The figure represents a generalization of the data, and an explanation of its construction is given in the next 30 LAG DAYS AFTER MOLT BASAL GROWTH PLATEAU 36 PREMOLT .GROWTH Figure 8. Type 2 neurosecretory cell counts and R values of crayfish with regenerating limbs at the indicated times during the period of regeneration. After animals with regenerating limbs had molted, the R values for each animal were plotted against the per cent of the growth period, and smooth curves were drawn through the points. The growth period in this case included the time from the first appearance of a regenerating limb to the molt of the animal. From each of the curves, R values were obtained at 10% intervals of the growth period. Tf the mean lag period of 6 days is subtracted from the mean intermolt period of 36 days, each 10% interval in the growth period is equivalent to three days of the mean intermolt period. In Figure 8 the mean R values are plotted at each three-day interval. Also plotted are the type 2 cell counts from Table I. The mean length of time required for the completion of basal growth was 10-11 days, and the type 2 cell count for that Stage was placed in the middle of that. 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 Lillie, Frank Rattray, 1870-1947; Moore, Carl
Size: 2059px × 1214px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectb, booksubjectzoology
