INTERNAL ANATOMY OF THE GAMASIN^. 295 



the capsule standing free in air in a longitudinal or diagonal, nearly horizontal, line 

 between the ventral surfaces of the male and female. The capsule itself is an elongated 

 flask almost parallel-sided and with a rounded distal end ; it narrows rather suddenly to 

 a short neck near the genital opening. This capsule, while still small compared 

 to what it will hecome, but already large in proportion to the creature, is drawn 

 in situ, (PI. XXXIII. fig. 3G) from a specimen of the male killed at this stage of coition ; 

 I have not found sperm-mother-cells in it at this period. If the Gamasids he not 

 killed so soon the capsule continues to distend until it is as long as the body of 

 the male, or even longer ; it still preserves nearly its original shape, but is rather 

 broader in proportion to its length than it is at first. If the creatures be killed at 

 this precise moment, which is not very easy to catch, the flask will be found still 

 with its small end in the genital opening of the male ; but it will be astonishingly large, 

 and will consist of a tolerably thick but clear and structureless exterior wall surrounding 

 a large number of spermatocysts precisely like the ripe sperm-mother-cells found in the 

 proximal part of the testis, and undoubtedly the same bodies. The capsule is filled up 

 by a clear but thickish fluid, and contains a multitude of minute granules ; the small 

 end is closed by gummy and granular matter. A capsule taken in this stage is 

 delineated (fig. 37). 



If the creatures be not killed so soon, but are allowed to complete the coitus, the male 

 now exerts both its mandibles and passes them one on each side of the spermatic 

 capsule ; the capsule, which apparently has about it viscid material which more or less 

 sets on exposure to the air, adheres to the inner sides of both mandibles, usually to the 

 small brush or row of hairs on each mandible which is inserted close behind the 

 articulation of the movable arm of the chela ; the mandibles are now moved away, 

 carrying the spermatic capsule, the small end of which is near the mandibles, but is left 

 free ; this small end is applied to the female. The capsule is evidently highly elastic, 

 so much so that it is very difficult to preserve it full; its elasticity usually drives the 

 slight stopping out of the small end and the whole contents of the capsule are discharged 

 upon the slide ; when this process takes place in nature of course the coitus is complete. 

 After the contents have been discharged the capsule remains attached to the mandibles ; 

 it retains its shape, but has shrunk to about the size shown in fig. 38. If the creatures 

 he killed at any time after the capsule has become attached to the mandibles of the 

 male and before the separation of the two creatures, the capsule will probably discharge 

 if it has not already done so ; the empty capsule, still retaining its form but not its size, 

 will be found attached to the two mandibles. Fig. 38 shows the rostrum of a male 

 H. hirsulus killed at this stage with the capsule still in the mandibles. Fig. 39 shows 

 the rostrum of a male of Lcelaps cuneifer killed under similar circumstances. If the 

 creature be not killed at all, the male may be watched cleaning his mandibles, and 

 getting rid of the capsule and other matter which adheres to them. 



It will be seen that the form of the capsule in L. cuneifer is different from that of 

 H. hirsutus, being a much shorter and rounder flask ; each form is quite constant in the 

 species to which it is referred ; otherwise the process is similar. Gaiuasus terribilis has 

 a capsule also constant in form, but almost the same as that of L. cuneifer, for which 



