102 BRITISH 



minate in the long, extensible ovipositor found in that 

 family. 



JSTalepa says that the oviducts in Tyroglyphus longior 

 start from the anterior poles of the ovaries and run 

 forward close to the ventral wall and near to each other 

 until they approach the vulva ; that they then bend 

 sharply backward, but remain ventral, until they reach 

 the ovaries once more, when they turn upward, for- 

 ward, and outward ; pass outside the caeca of the ven- 

 triculus ; then turn inward, and join below the colon ; 

 their walls, he says, are a soft tunica propria ; the epi- 

 thelium is homogeneous in the virgin female, and con- 

 sists of small, almost cubical cells, with large round 

 nuclei, granular contents, and distinct walls ; all which 

 become almost or quite invisible after the eggs have 

 distended the oviduct. 



In Garpoglyphus anonymux Nalepa says that the ovi- 

 ducts are S-shaped, and that in the virgin female they 

 are only about 12 /u in diameter, but must stretch to 

 six times that to pass the eggs. Their walls are then 

 so thin and transparent that the eggs appear to be free 

 in the body cavity. 



Haller,* dealing with T. longior, the same species 

 that Nalepa worked upon, said that the eggs stretch 

 forward in a simple chain from each ovary ; from this 

 chain he says that the eggs are constricted off sideways 

 and fall into the body cavity. The constriction-off 

 extends to the surrounding envelope, which becomes 

 an external coating to the egg. The oviduct, accord- 

 ing to this author, is a simple egg-tube, blind pos- 

 teriorly, into which the eggs entered from the body 

 cavity by means of an opening in its wall which is 

 usually closed by a door ; the ovary he says is pro- 

 vided with numerous stalked pockets, into one of which 

 the egg enters, the stalked passage being closed behind 

 it by a door ; what becomes of the egg subsequently 

 Haller omitted to state. How Haller came to describe 

 this very curious and complicated arrangement I am 



* 'Zur Kenntniss,' p. 286. 



