184 Mr H. Goodsir on the Development of the 



didymis, and even higher up the gland, for in general all these parent 

 or secondary cells are thrown into the spermatheca of the female before 

 they burst. Preparations, however, for this destruction of the parent 

 cell seem to be going on in the vas deferens of the male a long time even 

 before the testicle has arrived at its maximum state of periodic develope- 

 ment, for the difference between the cells in the epididymis and vas 

 deferens is quite apparent. Those in the former are quite full of young 

 cells, the walls of the parent cell lying tightly and closely upon, and 

 binding them together as it were ; whereas those in the latter, although 

 quite distended, are not full altogether of cells, but with a fluid which 

 appears to separate the young contained cells from one another, and 

 from the walls of the parent cell. If a female crab can be procured 

 shortly before spawning, the spermatheca will be found quite full of 

 these 3"oung cells, which we shall henceforth term primary, or sperma- 

 tozoal cells, with a few parent or secondary cells floating amongst 

 them. If the crab is still farther advanced, we will find that these se- 

 condary cells have disappeared altogether. These cells in the sperma- 

 theca are suspended in a thick albuminous fluid of a milky colour. 

 Throughout the whole course of the testicle and epididymis, we find 

 floating in a thick glairy fluid, along with the cells, in masses of an irre- 

 gular-shaped, clear-looking appearance, a substance which apparently 

 forms the nutriment of the cells, for this substance is always found in 

 greatest quantities high up the organ, where the secondary cells are in 

 an active state of growth and secretion, and of course requiring a supply 

 of nourishment ; whereas in the vas deferens, after the cells have arrived 

 to a state of maturity, little or none of this substance is found. How 

 this substance is secreted, or in what part of the organ, I have not yet 

 been able to ascertain. The above description of the secretion and de- 

 velopement of the seminal fluid refers to all the Crustacea. It will be 

 found, however, that this fluid varies more or less in its character in al- 

 most each species. In the May and June Nos. of the Ann. des Sc. Nat., 

 a translation of a paper will be found, '^ On the Seminal Fluid of the 

 Crustacea and Cirripeda ; by M. Kolliker of Zurich. That gentleman, 

 in the above paper, looks upon the filiform bodies which are found in 

 such numbers generally in the interior of the testicle of the lower Crus- 

 tacea, as the spermatozoa. Now, as far as my observations have gone, 

 it appears to me that these are parasitic entozoa (Filaria). My observa- 

 tions had been directed to these animals sometime before I had seen M. 

 Kolliker's paper, at which time I had made up my mind as to their para- 

 sitic character, and for the following reasons : From observations on 

 the origin and developement of the spermatozoa in the higher Crustacea, 

 it had been made out that these were developed from cells, and from 

 cells only. Now in every instance these Filaria were always found to be 

 the same, never changing their characters in the slightest degree. Be- 

 sides, the developement of the seminal cells in these lower Crustacea, 

 was always going on in the same way as it did in the higher, and with- 



