. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VIVIPARITY IN THE GENUS SEBASTES 363. Figure 5. Histological sections of gut tissue in various stages of embryonic Sebastes melanops. a. Stage 21 embryo (13 days post-fertilization), midgut region dorsal to the yolk sac. Note the columnar gut epithelium and empty lumen (scale bar = 20 /nm)- b. Longitudinal section of the midgut-hindgut region of a stage 28 embryo (24 days post-fertilization). Note the densely staining, acidophilic substance throughout the lumen of the gut (scale bar = 50 ^lm). c. Cross section of the hindgut
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. VIVIPARITY IN THE GENUS SEBASTES 363. Figure 5. Histological sections of gut tissue in various stages of embryonic Sebastes melanops. a. Stage 21 embryo (13 days post-fertilization), midgut region dorsal to the yolk sac. Note the columnar gut epithelium and empty lumen (scale bar = 20 /nm)- b. Longitudinal section of the midgut-hindgut region of a stage 28 embryo (24 days post-fertilization). Note the densely staining, acidophilic substance throughout the lumen of the gut (scale bar = 50 ^lm). c. Cross section of the hindgut of a stage 28 embryo. Note the expanded hindgut epithelium with material in the lumen (scale bar = 20 ^m). d. Cross section of the hindgut of a stage 31 embryo (29 days post-fertilization). The lumen contains an amorphous, granular substance, and the epithelial cells are characterized by supranuclear granules (scale bar = 20 tixn). (h = hindgut epithelium; 1 = lumen; m = midgut epithelium; y = yolk sac.) that of Hsaio (unpubl.), however, supports the idea of lecithotrophic viviparity in S. marinus. He demonstrated ". .a pronounced fall in the dry weight of the developing egg, indicating little or no maternal contribution" (Needham, 1942). The only accessible data of Hsaio, however, are presented in Scrimshaw (1945), where the dry weight of the newly fertilized egg is presented as g. This value is more than an order of magnitude greater than dry weights observed in the present study (Table I), and in Moser (1967a), which are in the range of 70-100 g. While the egg size in S. marinus is slightly larger than that of some Pacific species (Taning, 1961), it is doubtful that it could be 30-fold greater in dry weight. We therefore consider his unpublished values unreliable. Our value for PEC, , could conceivably be at the upper range of oviparous or lecithotrophic viviparous species (Table III). Furthermore, the value of AEE determined by oxgyen consumption is wit
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