. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. CLOACA AND SPERMATHECA OF GYRINOPHILUS. 26l expands into two short but thick lateral branches. These branches curve both latero-ventrad and caudad (Figs. 5 and 12). Into them and into the distal end of the common tube open small flask-shaped tubules, with long slender necks and bulbous, blind ends; these are bilaterally arranged in two groups, varying from fifteen to twenty-five in each group in different animals. Rarely a tubule is double: , one slender neck terminates in two bulbs. The tubules point caudad, dorso-cauda
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. CLOACA AND SPERMATHECA OF GYRINOPHILUS. 26l expands into two short but thick lateral branches. These branches curve both latero-ventrad and caudad (Figs. 5 and 12). Into them and into the distal end of the common tube open small flask-shaped tubules, with long slender necks and bulbous, blind ends; these are bilaterally arranged in two groups, varying from fifteen to twenty-five in each group in different animals. Rarely a tubule is double: , one slender neck terminates in two bulbs. The tubules point caudad, dorso-caudad, laterad and ventrad, but not cephalad and not directly dorsad. Sperma- tozoa, when abundant, are found in the common tube, its branches, and in both neck and bulb of the tubules (Fig. 12). In the bulbs they are arranged in a whorl (Fig. 13), lying side by side, heads all pointing in the same direction. A similar cluster is sometimes found streaming into the neck of a tubule, but in other necks and in the common tube, there are only a few stray sperms. When sperms are scanty, they are tangled and disordered, as though they had been brushed off when the larger clump was expelled by muscular contraction, and are found in the lateral branches of the common tube, and in some tubules, but are absent from others. Surrounding the organ as a whole, as well as each tubule and the common tube, are numerous plain muscle fibers. Pigment cells, containing coarse black or brown granules, are found to be most abundant around the expanded end of each tubule, moder- ately abundant in the dorsal elevation, and scanty beneath the epithelium of the rest of the cloaca, among the muscle fibers of its wall, and about the ureters. The epithelium of the spermatheca is stratified in the common tube and its branches, the surface layer of columnar cells be- coming progressively taller toward the upper end of the tube. It becomes a simple, low columnar in the necks of the tubules, and a simple, tall colu
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
