49 



applying to its final position is more applicable. The outer wall of the case is a 

 thick cylinder of chitin-like material, marked by distinct striations parallel to its 

 surface. It is perforated at its distal end for the passage of the filament. The 

 inner wall of the case is thin. Between these two walls is a granular fluid 

 which separates them widely at the proximal end of the case, but which is 

 scanty at the distal end where the walls are close together and are connected 

 by a few fibres. About one ninth of the length of the case from its distal end a 

 number of apparently contractile fibres encircle the inner wall of the case and 

 press it upon the flask apparatus. The spermatophoric case encloses a trans- 

 parent fluid in which lies the sperm rope , occupying its middle two fourths and 

 the flask apparatus filling its distal fourth; the greater portion of the fiuid 

 which often contains a few spermatozoa being gathered at the proximal end 

 of the case. The sperm are twisted into a rope which forms a closely coiled , 

 oblique spiral plate and which is enclosed by a delicate membrane. The proximal 

 end of the rope bears a knob-like protuberance consisting of some sticky sub- 

 stance, by means of which it is attached to the buccal membrane of the female 

 after the discharge of the spermatophore. The flask apparatus consists of a flask- 

 shaped sac which is prolonged into the filament and which is partly enclosed 

 by an outer tube. The latter , the outer flask tube , is apparently continuous 

 with the inner wafl of the case. It contains the proximal portion of the filament 

 and is attached to the shoulder of the flask. The proximal portion of the outer 

 flask tube is double waUed , the space between the wafls being filled with a 

 slightly opaque fluid. Just beyond the constricted portion of the inner wall of 

 the case, the walls of the outer flask tube diverge so as to enclose a ring- 

 shaped cavity beyond which the two walls fuse. The single walled portion of 

 this tube is somewhat convoluted. The flask is attached to the sperm rope by 

 a slender tube which seems to be continuous both with the flask's wall and 

 with the sheath of the sperm rope. The flask is filled with a dense fiuid which 

 does not seem to contain sperm , and it tapers into a neck-like portion which is 

 separated from the filament by a slight constriction, where a break usually 

 occurs as the spermatophore is discharged. The filament is a continuation of the 

 flask and passes thru the outer fiask tube to the exterior. The inner wall of the 

 proximal portion of the filament bears a dextrose spiral thickening, the "spring", 

 which extends from the base of the filament to a point somewhat beyond the 

 enlargement of the outer flask tube. The filament beyond the spring is smafler, 

 and , after a few convolutions , passes out of the case of the spermatophore. The 

 free portion of the filament is as long as, or longer than the spermatophore, 

 but since it remains attached to the penis, or to the spermatophoric sac, it is 



