North American Parasitic Copepods of the Family Argulidae; With a Bibliography of the Group and a Systematic Review of All Known Species

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1902. Excerpt: ... seminal receptacles in the female. They are much larger than the receptacles, however, and as a result the abdomen of the male is comparatively larger and longer than that of the female of the same species. The testes (t.) are ovoid or ellipsoidal in shape, and in neaily every species are covered on the dorsal surface with dark pigment spots corresponding to those on the dorsal surface of the ovary. From the Fig. 23.--Male Sexual Organs Of Argulus Americanus. 6. c, Blind Capsule; e. d., Ejaculatoby Duct; S. V., Semen Vesicle; t., Testis; V. d., Vas Deferens; V. e., Vas Efferens. anterior end of each testis there runs a duct, the vas efferens (v. e.), which leads forward to the unpaired seminal receptacle or vesicle (s. v.) lying in the posterior thorax on the midline, above the intestine. The vasa efferentia enter the vesicle at its posterior end. From the anterior end there is given off on either side another duct, the vas deferens (v.d.), which turns backward alongside the vas efferens until it reaches the posterior border of the thorax, where it turns downward and inward, meeting the corresponding duct from the other side on the midventral line and fusing in a very short, common ejaculatory duct (e. d.) which opens at the base of the sinus, between the lobes of the posterior legs, thus corresponding exactly to the opening of the oviduct in the female. Connected with the vasa deferentia on either side, just where they turn down to meet each other, is a pair of accessory blind capsules (b. c). These are long and slender, and reach forward far beyond the seminal vesicle and are somewhat enlarged at their anterior ends so as to be club-shaped. All the ducts and the seminal vesicle exhibit peristaltic movements. The accessory sexual organs of the male are u...