. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. STARFISH FEEDING AND REPRODUCTION 135 ORGAN INDEX 20 15 10 GONAD INDEX HEPATIC INDEX INDEX SUM PERCENT FEEDING. 00 80 PERCENT FEEDING 60 40 20 1962 1963 j 1964 FIGURE 3. Seasonal changes in the gonad and hepatic indices, per cent feeding, and the sum of the gonad and hepatic indices. Note that the organ indices are approximately inverse to each other, and that the feeding curve is similar to that of the hepatic index, but delayed about 4 months. in May; the index rises all summer to a peak in November, and falls until the ne
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. STARFISH FEEDING AND REPRODUCTION 135 ORGAN INDEX 20 15 10 GONAD INDEX HEPATIC INDEX INDEX SUM PERCENT FEEDING. 00 80 PERCENT FEEDING 60 40 20 1962 1963 j 1964 FIGURE 3. Seasonal changes in the gonad and hepatic indices, per cent feeding, and the sum of the gonad and hepatic indices. Note that the organ indices are approximately inverse to each other, and that the feeding curve is similar to that of the hepatic index, but delayed about 4 months. in May; the index rises all summer to a peak in November, and falls until the next spring (Fig. 3). There is no significant difference between the male and female hepatic index. HISTOLOGY Specimens of the excised organs of each starfish obtained at each sampling were preserved in Bouin's fluid for subsequent histological observations. These provide both general confirmation of the gross changes in size, and some details as to what is involved in these changes. The tissues were imbedded in paraffin, sectioned at 5 p, and stained with Harris' hematoxylin and eosin, Mallory's triple stain, or the periodic acid-Schiff routine (PAS), counterstained with Harris' hematoxylin (Pantin, 1946; McManus and Mawry, 1960). Salivary amylase digestion was used in conjunction with some of the PAS material. Sections were made of the ovaries of three females from samples collected on September 14, 1962 (Fig. 4), December 25, 1962, and April 8, 1963 (Fig. 5). The gonad indices of the females were , and , respectively; the gonad indices of the samples from which they were taken were , and , respectively. In September, the oocytes (Fig. 4) have diameters between 10 and 50 /x; in December, they range from about 10 /A to 150 yu,; in April (Fig. 5) there are two size groups, one about 150 /*, and the others less than 20 /j,. Below about 20 p, they are PAS-negative; above that size the oocytes become progressively more and more PAS-positive. The very inten
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
