. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OVUM. [123] In others of the Nematoid Worms and more especially in Strongylus and the Gordiacei, it would appear from the researches of Meiss- ner, that the first germs of ova which take origin in the uppermost part of the ovarian tube multiply by an endogenous production, and that in this manner groups or bunches of the primitive ova are produced which are con- nected together by pedicles arising from the Fig. 89*. Formation and fecundation of the ova of Nematoid Worms. {According to Meissner.) a. A portion of the ovari
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. OVUM. [123] In others of the Nematoid Worms and more especially in Strongylus and the Gordiacei, it would appear from the researches of Meiss- ner, that the first germs of ova which take origin in the uppermost part of the ovarian tube multiply by an endogenous production, and that in this manner groups or bunches of the primitive ova are produced which are con- nected together by pedicles arising from the Fig. 89*. Formation and fecundation of the ova of Nematoid Worms. {According to Meissner.) a. A portion of the ovarian axis and early ova attached to it from the ovarian tube of Strongylus armatus. The axis column occupies the centre of the tube, and the ova are suspended to it by pedicles, supposed by Meissner to form micropyle apertures when they are detached. b. View given by Meissner of a set of the nearly ripe ova of Ascaris mystax, which he conceives are thus connected by pedicles to a central axis. c. Two mature ova of the same surrounded and in part penetrated by spermatic corpuscles. At the narrow angles of these ova a spermatozoon is seen passing into the interior by what Meissner has regarded as a micropyle formed by the detached pedicle. In the ovum to the right a spermatic cor- puscle is seen in the vitelline substance. The existence of such a micropyle aperture and pedicu- lated attachment of the ova in the Ascarides 1 re- gard as doubtful. <7. Formation of ova and fecundation in Gordlus Sub- bifurcus. {From Meissner.) a. A small portion of the ovarian tube with groups of the ova partly within and partly escaping from it. b. Three of the mature ova from the lower part of the oviduct surrounded by the spermatozoa. The ova are now isolated, and "the pedicle of each is open, and is regarded by Meissner as a micropyle, by which spermatozoa, as represented in two of them, enter the ova. The germinal vesicle is still to be seen. elongated membrane of the original germ-cell w
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