. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. \\ KIGHT AND WATER CONTENT OF PASSALUS 27 emerged) males was found to be 1478 mgs.; and of 35 old females, 1686 mgs. The range in weight of males was from 977 mgs. to 1740 mgs.; of females, from 1390 mgs. to 1972 mgs. Newly hatched larvae contain about 85 per cent water. As soon as the larvae begin feeding the water content rises to about 90 per cent. This percentage is maintained until the larva ceases feeding and enters the prepupal stage when it falls to 88 per cent. There is then a steady increase in percentage of water
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. \\ KIGHT AND WATER CONTENT OF PASSALUS 27 emerged) males was found to be 1478 mgs.; and of 35 old females, 1686 mgs. The range in weight of males was from 977 mgs. to 1740 mgs.; of females, from 1390 mgs. to 1972 mgs. Newly hatched larvae contain about 85 per cent water. As soon as the larvae begin feeding the water content rises to about 90 per cent. This percentage is maintained until the larva ceases feeding and enters the prepupal stage when it falls to 88 per cent. There is then a steady increase in percentage of water until a high of 93 per cent is reached in the late pupal stage. The changes in water content in the prepupa coincide with the changes in weight, but in the pupa the weight re- mains constant while the percentage of water increases. A loss in dry weight is apparent as the internal tissues undergo histolysis. On emergence of the adult the per cent of water does not fall abruptly to the low level of old black adults, but de- clines gradually. The total weight of the adult, however, remains essentially con- stant so that the gradual decrease in percentage of water is explained by a gradual loo-•. 60- 60 III 3AI8 FIGURE 4. The water content, in per cent, throughout the life cycle of Passalus comutus. e, egg; L, newly hatched larva; pp, beginning of prepupal stage; p, beginning of pupal stage; na, newly transformed adult. increase in dry weight. The red color of newly emerged adults persists for several weeks and may last for several months, but as the red gradually gives way to brown and the brown to black, the percentage of water falls until it finally reaches the level of 67 per cent for old adults. Twelve adults a month after emergence were found to still contain as much as per cent water. No appreciable difference in the water content of males and females was observed. A curve of the changes in percentage of water content from egg to adult is shown in Figure 4. DISCUSSION
Size: 2144px × 1166px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
