256 VERA KOEHRING. 



tubule into the cloaca is minute and the very short duct above is 

 broader in diameter. Columnar epithelium is already present 

 lining this little chamber. There is no sign of the columnar 

 epithelium in the necks or dense cells of the two primary tubules- 



A 64 mm. animal, an adult probably recently transformed, 

 shows another pair of tubules and otherwise little change in the 

 spermatheca development, though the cloacal glands are greater 

 in number and length and the cloaca is beginning to form folds 

 of the walls. 



In a 66 mm. animal there is another pair of tubules thus 

 making four tubules on a side. The tubules seem to be all of 

 the same size; the blind ends show an open lumen; the necks 

 are solid cords. The central tubule is no larger in size and 

 extent that it was in the 58 and 59 mm. animals but it is further 

 removed from the cloacal wall more dorsal. There seems to be 

 no opening at all into the cloaca. It is not probable that any 

 sections are lost in this region which might account for not 

 finding an opening. The organ at this time is functionless and 

 is developing slowly ; on the other hand the cloaca is developing 

 steadily, that is, the walls are becoming folded and glands are 

 enlarging. The spermatheca group of tubules is left behind 

 until the approach of sexual maturity. 



A 68 mm. animal was sectioned horizontally and badly torn 

 by inability to fix the contents of the rectum, but there is dis- 

 cernible the same primitive condition as of the 66 mm. female. 

 The number of tubules has increased; five pairs are certain but 

 six may be present. All are in the same stage. In all these 

 series there is no way of determining the primary pair of tubules 

 nor the latest formed. 



From the first few rudimentary tubules with their cord-like 

 necks and small central tubule and the whole without any sign 

 of pigment, to the pigment-walled mature spermatheca which 

 occurs in so many 68-72 mm. females and in practically all of 

 them of greater length, seems a great jump and implies rapid 

 growth in a short period most probably just preceding the first 

 egg-laying season. The author regards it as a piece of good-luck 

 to have found, simply by chance sectioning, as there seems to be 

 no other method of determining age at this period, a series 



