. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 60 A. N. SASTRY 20 x LU Q Q uj 10 UJ o WOODS HOLE ( r=- , ft>005) BEAUFORTtr =, ). 0 10 15 20 GONAD INDEX 25 FIGURE 4. Correlation between monthly mean gonad index and the digestive gland index of the populations of scallops. synthesis of various biochemical constituents (Marshall and Orr, 1961; Giese, 1959; Barnes, Barnes and Finlayson, 1963; Sastry, 1966a, 1968). The changes in the monthly gonad and digestive gland indexes in some marine invertebrates show a reciprocal relationship suggesting the influence
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 60 A. N. SASTRY 20 x LU Q Q uj 10 UJ o WOODS HOLE ( r=- , ft>005) BEAUFORTtr =, ). 0 10 15 20 GONAD INDEX 25 FIGURE 4. Correlation between monthly mean gonad index and the digestive gland index of the populations of scallops. synthesis of various biochemical constituents (Marshall and Orr, 1961; Giese, 1959; Barnes, Barnes and Finlayson, 1963; Sastry, 1966a, 1968). The changes in the monthly gonad and digestive gland indexes in some marine invertebrates show a reciprocal relationship suggesting the influence of food on gonad growth (Giese, 1959; Sastry, 1966a, 1968). The digestive gland index of the scallop populations is at a relatively higher level than the gonad index during the vegetative and rest- ing periods (Fig. 2). To determine the significance of the relationship, correlation coefficients were computed. Both populations showed a negative correlation, but this was significant at the 5% probability level only for the population at Woods Hole (Fig. 4). The changes in the monthly digestive gland index probably indi- cates the amounts of nutrient reserves in the tissue which vary with gonad growth activity and seasonal changes in the environment. In a number of laboratory ex- periments, it has been shown that scallops in the resting stage require abundant food and exposure to minimum temperature to begin gonad growth (Sastry, 1968). The nutrient reserves present in the digestive gland, however, are obviously not adequate to sustain gonad growth. Continuing growth is apparently related to periods of abundant food production. Garnet agenesis The predominant stages in gametogenesis observed in the two populations of scallops an- given in Table II. Similar stages in gametogenesis appear in both populations during different months of the year. The Woods Hole population develops oogonia by March, and the oocytes begin the synchronous growth phase. Please note that these images are
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
