308 ME. A. D. MICHAEL ON THE VARIATIONS IN THE 



where I know that the capsule is discharged into the vagina, there is a distinct 

 spermatheca, usually filled with sperm, leading out of or forming part of the vagina, 

 which does not exist in any of the species that possess the sacculus or ringed tuhes. 

 It is also worthy of remark that in the one species investigated which has not possessed 

 either the sacculus or this vaginal spermatheca or recess {Lcelaps ligoniformis) there is 

 what I should judge to he a spermatheca (PI. XXXIV. fig. 66) just at the opening of 

 each ringed tuhe, and this does not exist in any of the other species. 



It is also to be remembered that in most spiders, e. g. Tetragnatha, Theridium 

 4-punctatum, &c, the spermathecse do not open into the vulva, but have separate 

 external apertures *. In the spiders, or most of them, the spermatozoa are contained 

 in spermatophores or spermatocysts. 



Taking all these matters into consideration, I incline to think, although I should 

 not like to state it as a fixed opinion, that in what I may call the sacculus species 

 the sperm-elements enter the body of the female by the ringed tubes, and not by the 

 vagina.' 



Prom the above-described facts, and particularly having regard to the great change 

 which takes place in the sperm-elements of Hcemogamasus hirsutus hetween the time 

 when they are found in the capsula spermatis and that when they enter the camera 

 spermatis, I think that the following is probably the function and action of the 

 female organs above described, viz. : — That the germ-elements are produced in the 

 arms of the lyrate organ, and gradually work their way to the base of that organ, 

 where they break off and pass into or by the base of the camera spermatis ; that the 

 sperm or spermatocysts enter the sacculus probably, but not certainly, by way of the 

 ringed tubes and rami ; that the spermatozoa are at that time not fully developed, 

 and that they only attain their final development within the body of the female; 

 that the sacculus with its cornu, and diverticula when present, is the organ in which 

 this development takes place, and whose office it is to mature the spermatozoa ; that 

 when the spermatozoa are really ripe they pass out of the cornu into the camera 

 spermatis ; that there they meet the germs and fertilize them ; that the ova then 

 lodge in what is called the ovary and form oocysts by the outpushing of its walls ; 

 that in these oocysts they attain a considerable amount of development, although 

 probably not as high a state of maturity as they will attain in the oviduct, whence 

 they pass through the vagina to the exterior. 



It may be suggested with considerable force that this explanation fails in the case 

 of such species as Lcelaps vacua and L. cuneifer, where there is not any apparent 

 connection between the cornu and the camera spermatis or ovary ; I cannot help 

 thinking, however, that, although I have not found it, this connection must exist 

 at some time of year or under some circumstances ; I cannot otherwise understand 

 the presence of abundant spermatocysts in the sacculus. 



Finally it remains to account for the function of the organs in such a species as 

 Holotasiris monticagus, with its three little hollow balls forming a trefoil within the 



* Bertkau, " Ueber den Generationsapparat der Araueiden," Arcliiv fiir Naturgesch. 1875, p. 285. 



