THE SPERMATHECA OF EURYCEA BISLINEATA. 253 



to be very old animals there are two of these reservoirs formed 

 by the necks of each side; these join, narrow and become the 

 central tubule. The lumen of this tubule near the opening into 

 the cloaca is often very small about i/ioo mm. but it may be 

 as wide as 4/100 mm. The lumina of the necks vary around 

 i/ioo mm. and those of the flask ends are usually about 6/100 

 mm. in diameter. 



The dense coat of pigmented tissue, covering and binding in 

 place the tubules, has been spoken of. This coat is thin, some- 

 times of but a few strands on the roof of the spermatheca. It 

 is along this dorsal region that the central duct lies. This duct 

 and the necks are surrounded by massed smooth muscle fibers 

 which do not differ from the smooth muscle of the walls of the 

 cloaca. 



Unless injected, it is difficult in amphibian material to study 

 the blood supply of an organ. Red blood corpuscles stain 

 vividly with eosin and when present in numbers indicate blood 

 vessels and capillaries even when dense pigment is present. In 

 one series of a spermatheca which is on the verge of maturity 

 many blood corpuscles have remained in this region. It is 

 evident that the blood supply is rich. Corpuscles running single 

 file everywhere throughout the region of the spermatheca indicate 

 a close network of capillaries and some larger blood vessels are 

 present. Only injection would show certainly, however, just 

 where these vessels branch from the dorsal aorta which lies 

 immediately above the spermatheca. 



The mating of Eurycea takes place in the spring. There have 

 been no spermatozoa found in the spermatheca during the fall 

 and winter months. April may be taken as the average mating 

 season though there must be as variable a season for mating as 

 there is for egg-laying and many early and late dates have been 

 recorded for Eurycea eggs. 



Spermatozoa are found in the flask tubules usually in dense, 

 orderly whorls similar to the groups found in the vas deferens 

 of the male. They may be, however, scattered and tangled. 

 No spermatozoa have been found in the central tubule in any 

 series I have sectioned and in but one are there any in the 

 necks of the tubules. This is a sagittal series and some sections, 



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