Spermatheca Sentence Examples
In Heliodrilus the blind extremity of the spermatheca is enclosed in a coelomic sac which is in connexion with the sacs envolving the ovaries and oviducts.
In Hyperiodrilus the whole spermatheca is thus included in a corresponding sac, which is of great extent.
In such other genera of the family as have been examined, the true spermatheca has entirely disappeared, and the sac which contains it in Hyperiodrilus alone remains.
We have thus the replacement of a spermatheca, corresponding to those of the remaining families of Oligochaeta, and derived, as is believed, from the epidermis, by a structure performing the same function, but derived from the mesoblastic tissues, and with a cavity which is coelom.
Spermatheca rarely with diverticula; sperm ducts as a rule occupying two segments only, usually opening by means of an atrium.Advertisement
In the former, the duct, leading from the ovarian sac, and swelling along its course into the spherical sac, the "spermatheca," is highly suggestive of the oviduct and receptaculum of the Eudrilidae.
Soon after quitting the uterus it is joined by a long duct leading from a glandular sac, the spermatheca (Rf).
Spermatheca or receptacle of the sperm in copulation, opening into the female duct.
Fertilization takes place as the egg is laid, the spermatozoa being ejected from the spermatheca of the female and making their way to the protoplasm of the egg through openings (rnicropyles) in its firm envelope.
The median vagina, spermatheca and ejaculatory duct are, on the other hand, formed by ectodermal inpushings.Advertisement
In Helix hortensis the spermatheca is simple.
But in rare cases in Helix aspersa a second spermatheca is found at the end of this second duct.