456 
Proceedings of the Royal Society 
diverticula just mentioned, is a large pouch in the posterior region of 
the segment, connected with a 
small diverticulum in the follow- 
ing segment ; in segments ten and 
eleven were a pair of pouches 
lying close to the posterior mes- 
entery, and apparently unpro- 
vided with any diverticulum. The 
pouches were in every case fully 
distended with the contained 
semen. I also studied the series 
of copulatory pouches of one side 
of the body (the right) by means 
of longitudinal sections, which 
revealed the position of the ex- 
ternal apertures not visible on an 
inspection of the intact worm. 
These apertures are situated at 
the anterior extremity of each 
segment, in the groove which 
separates it from the segment 
in front and on a line with the 
innermost seta of the more dor- 
sally placed pair. It has been 
already mentioned that the copu- 
latory pouches themselves Me in 
most instances in the posterior 
region of their segments, in close 
contact with its posterior wall. 
The duct of each pouch, which is 
extremely narrow, perforates the 
body wall just at the point where 
_ _ n-, „ the mesenteries arise, and, run- 
Fio. 2.— Diagram of longitudinal sec- ’ ’ 
tion through spermathecse of right n ing obliquely backwards, opens 
side of body. The spermatheca A . . ., , 
at the top of the figure is the last, on to the exterior m the place 
i- e -i that occupying segment 11; a i rea( jy mentioned, which corre- 
mes, mesenteries ; c p, sperma- J 
theca ; e, epidermis ; m, trans- sponds with segment behind that 
verse muscular layer; m', longi- ... . , i ^ 
tudinal muscular layer. which contains the pouch itself. 
'e m 
TTV 
