PARASITES FOUND JN ECHINUS ESCULENTUS, L. 287 



Each branch of the ovary contains, as a rule, a single row of 

 large angular ova, with very large spherical nuclei. The ova 

 are mostly bounded by flat sides. They show some tendency 

 to squeeze one another out of the single row, and when this is 

 the case the row appeal's double. The ova at the end of each 

 branch next the outlet are markedly bigger and more rounded 

 than those near the top, where they are very small, and 

 apparently it is here that they arise. 



The coating of the ovary is thin, and it is continued in 

 each side into a short duct which unites with its fellow, and 

 at or near the point of union the ducts of the yolk-glands 

 open. 



The yolk-glands are large and branching; they lie on each 

 side of the body between the testes and the ovary, — on the 

 whole, more dorsal than the ovaries (fig. 2). The tissue of the 

 yolk-glands is dense, and stains deeply near the tips of the 

 branches; but it becomes much vacuolated and stains less 

 deeply near its opening, which leads into the duct of the yolk- 

 glands. 



The two oviducts of each side and the two ducts of the 

 yolk-glands open into a common chamber of somewhat angular 

 shape. 



The shell-glands are paired, and occupy much of the 

 posterior end of the body. The numerous little glands wdiich 

 constitute the organ are unicellular and generally somewhat 

 angular in shape, packed away as they are amongst the 

 interstices of the parenchyma. Ijach is crowded with fine 

 granules, and leads by a very delicate duct, which, converging 

 towards each side of the uterus, does not open into the yolk- 

 gland ovary complex, but as far as 1 can make out into the 

 uterus. 



In each specimen the uterus contained a beautiful golden 

 egg, oval in outline and continued posteriorly into a long 

 filament. This filament is bent and curved so as to form a 

 tangled skein in the centre of the body; gradually it becomes 

 finer, and its end, which is of extreme tenuity, lies in the 

 neighbourhood of the external opening of the uterus. The 



