SEA-FISHERIES LABORATORY. 101 
circularly-running series, looking lke an _ elongated 
sphincter, and a strongly developed radial series, the 
fibres of which run from the internal to the external wall. 
There are no longitudinal fibres. 
All this is very easy to make out, but it is exceedingly 
difficult to make sure of the connection of the vagina with 
the rest of the female organs. It will be seen from fig. 4 
that some denser tissue hes in the axis of the vagina 
beyond the apparent termination of the lumen. Now, if 
one uses an oil immersion lens it is easy to see that this 



4 
seneyVas delerens 

f vileprn, id 
. SP g us 
Fie. 4. Part of a horizontal section passing through the vagina. 
denser tissue represents a capillary tube, which runs 
backwards or laterally and pierces the wall of the enlarged 
vagina. Beyond this various coils of the (presumably) 
same very narrow tube can be seen, but it 1s difficult to 
connect them and follow their course : a complete coil may 
be contained in the thickness of one section; and I cannot 
be sure whether they open into the oviduct, or vitelline 
duct. It is fairly certain, however, that we are dealing 
here with a true seminal canal; that the dilatation of the 
vagina represents a true receptaculum seminis; but that 
the animals have not entered upon the phase in their life- 
