238 W. N. F. WOODLAND 



The fertilization chamber is a quite distinct permanent 

 spherical dilatation, sharply demarcated from both the oviduct 

 and the vagina by the narrow openings just referred to, and 

 with distinctive thick walls. It usually contains a large cluster 

 of eggs, and eggs of course are usually to be seen in the oviduct, 

 both anteriorly and posteriorly, but I have not been able to 

 detect either eggs or spermatozoa in the vagina, though the 

 eggs must make their exit by this duct and spermatozoa must 

 enter. The eggs (PL 18, fig. 10) in the fertihzation chamber 

 (which measure in diameter from 5-2 to 5-6 microns) and oviduct 

 appear to be fully mature, and are certainly not the mere 

 accidentally injected yolk-cells postulated by Dr. Plehn. One 

 trifling and yet in a waj^ important point to mention is that 

 the muscular walls of the dilated portions of the oviduct, 

 situated just below the ovaries, as well as the walls of the vas 

 deferens, show a marked longitudinal striation, and this stria- 

 tion, seen in optical or actual section in slides stained with 

 haematoxylin, bears a superficial resemblance to a mass of 

 spermatozoa, and it was this appearance I imagine which led 

 iJr. Plehn to assume that the portion of the oviduct behind 

 the ovaries represented a vagina. Starting from this assump- 

 tion, Dr. Plehn was logically led into the further assumptions : 

 (1) that a second female duct was present — the duct she 

 labelled ' Uterus ' and supposed by her to be continuous in 

 the young animal with the duct she labelled ' Dottergang ' 

 (PI. 18, fig. 11) ; ^ (2) that an ootype must be situated between 

 the bases of the two ovaries, but, it not being visible, it was 

 necessary to assume (3) that the animal was not mature, and 

 in view of this immaturity, (4) that the eggs plainly to be seen 

 in the oviduct and in my fertilization chamber were only yolk- 



^ Dr. Plehn says in her second paper that she had previously failed to 

 observe the ' ganz typische Cestodenvagina ' full of spermatozoa, but 

 a comparison of the figures in her first and second papers proves that the 

 ' Dottergang-uterus ' is the new second female duct figured and not the 

 ' vagina '. In her first paper the ' vagina ' (i. e. the oviduct) is shown 

 clearly (and correctly) in all its winding course and full of eggs, not sperma- 

 tozoa ; whereas, in her second paper, it is represented as of the same 

 form but devoid of eggs. 



