. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REPRODUCTIVE SYSTEM OF MYA ARENARIA 345 Photographs were made of various structures in the histological preparations and reconstructions in the form of sketches were made to clarify the spatial rela- tionships of the structures. Spawning of the living specimens was artificially induced by a cyclic fluctuation in water temperature, or in a few cases by injecting 1 ml. of N ammonium hydroxide into the gonad through the mantle strap. RESULTS In general arrangement, the reproductive system of Mya is similar in both sexes. Th
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. REPRODUCTIVE SYSTEM OF MYA ARENARIA 345 Photographs were made of various structures in the histological preparations and reconstructions in the form of sketches were made to clarify the spatial rela- tionships of the structures. Spawning of the living specimens was artificially induced by a cyclic fluctuation in water temperature, or in a few cases by injecting 1 ml. of N ammonium hydroxide into the gonad through the mantle strap. RESULTS In general arrangement, the reproductive system of Mya is similar in both sexes. The gonads are paired organs consisting of highly ramified tubules bearing numerous terminal and lateral alveoli. In a well-nourished, ripe individual these alveoli are closely packed and fill much of the visceral mass. The tubules of each gonad, by a series of confluences, eventually merge into a pair of gonoducts (Fig. 1). CEREBRO-VISCERAL COMMISSURE GENITAL VESICLE GENITAL APERTURE TRANSVERSE MUSCLE GONODUCT NERVE BRANCH GONAD FIGURE 1. Semi-diagrammatic reconstruction of the reproductive system and associated structures in Mya arcnaria. which lead caudad and dorsad towards the region of the genital apertures. The apertures are situated on tiny papillae located on either side of the dorsal apex of the visceral mass (Fig. 2), just anterior to the foot retractor muscle. According to Vies (1909), the gonads remain isolated from one another throughout the system, so that ink injected into one of the genital apertures will permeate the genital organ on one side of the clam only. While this mutual isolation seemed to be true in some of the individuals which I examined, in most specimens the gonoducts were joined in a common chamber or vesicle (Figs. 1 and 3), lying between and slightly anterior to the genital apertures. The vesicle is often bilobed, suggesting a tendency toward separation. Leading caudad and laterally from this vesicle are two short ducts (referred to henceforth as
Size: 1842px × 1357px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
