ORGANS FOR SPERM-TRANSFER 255 
mass. The cavity within the shell of the external mass is reduced 
to a narrow space and the glands have become few. 
Further along the stylet, (fig. 10) the groove has passed from 
opening to the left (fig. 8), through the position shown in fig. 9, 
to open more toward the right. The groove is a deep and narrow 
one. Into it still open some few gland ducts from the remaining 
glands of the median mass. As before the side walls of the groove 
are made of very thick shell. The most unexpected fact is that 
the bottom of the groove is shut off as a very minute hole overhung 
by the continuation of the lip, which is now a horny shelf passing 
all along the groove, near its bottom, and so nearly meeting the 
opposite side as to practically shut off the bottom of the groove 
as a special tube. This figure shows the form of the stylet at the 
level, 10, of fig. 6. The flat side to the left is the flat face of the 
median mass, while the rounded edges of the groove are the two 
narrow parts of the external and median masses seen from the 
ventral side in figs. I and 6, just proximal to the base of the spatula. 
A section through the base of the spatula, (fig. 11) shows the 
groove above overhung by the rising spatula that conceals it 
from surface view, (figs. 1 and 6) but still allows access to the 
groove from the right, in under the spatula base. The external 
mass (#zx. m.) is now the greater, but it contains no glands, while 
the median mass is reduced to a nearly solid shell prolonged as 
the slightly hollow spatula. The tube at the bottom of the groove 
is still there, overhung by the little chitinous shelf. 
Near the apex of the organ, (fig. 12) the groove is again open 
above, as we have passed beyond the base of the spatula, only the 
tip of which is cut, lying well over to the right. This figure being 
magnified twice the diameter of the preceding figures, shows 
plainly the shelf that cuts off the bottom of the groove. The 
median mass is a narrow and nearly solid shell that forms the left 
wall of the straight, deep groove, The external mass is the main 
part of the section and contains much very watery connective 
tissue, covered with epidermis. In this section, the calcified 
part of the shell is represented in black, as in the other sections, 
while the chitinous or horny parts are dotted. From the surface 
this region of the canula looks to be only chitin. Farther on the 
JOURNAL OF MORPHOLOGY, VOL. 22, NO. 2. 
