intromittent

Conveying, sending or passing into a body.

And, in the end, there must be a way for the developed young to leave the maternal nidus, and the intromittent canal may answer this purpose or, by chance, it may not.

1990, Raymond R. Forster, Norman I. Platnick, Jonathan A. Coddington, A Proposal and Review of the Spider Family Synotaxidae (Araneae, Araneoidea), American Museum of Natural History, page 39, Epigynum well developed, often with prominent paired lobes; internal female genitalia consisting of two widely separated pairs of receptacula with short intromittent ducts; […] .

Used for intromission.