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



Lcelaps Icevis ; x 75. The figure is to give an idea of the arrangement of the parts relatively 

 to one another • it is taken looking down from above, after the dorsal plate, the fatty matter 

 underlyino- it, and such muscles as interfered with the view hud been removed. The whole 

 of the ventriculus and its anterior and its upper posterior cieca are seen (light) ; the lower 

 pasterior cEeca just show (dark). The hind gut is hidden by the saeculus fcemineus and its 

 cornu wiiieh are in the centre, and by the ova. The most mature ovum, ovr, must in one 

 respect be considered diagrammatic, because it should have been drawn very much larger ; but 

 to have made it the full size would have greatly increased the size of the figure without corre- 

 sponding advantage, and would have obscured parts of the C£eca which I wished to show. The 

 distal ends of the lyrate organ are seen (dark) projecting from below the anterior lateral cseca of 

 the ventriculus. The oesophagus and pharynx are not drawn, as they are not in the part of the 

 body where the genital and alimentary systems intei-lock. 

 Fig. 47. Terminal portion of one of the arms of the lyrate organ of an adult female Hcemor/amasus 

 hirsutus; x 275. To show the cellulation, &c. 



Plate XXXIV. 



Fig. 48, The saeculus fcemineus, with its upper appendages, &c., and the lyrate organ and ovary of an 

 adult female Hamogamasus horridiis (page 297), in situ, seen from above ; x 60. The central 

 part of the lyrate organ and of the ovary, and the camera spermatis and oviduct, are hidden 

 by the saeculus, which contains numerous spermatocysts, &c. The cornu sacculi contains 

 similar bodies, and passes underneath to the camera spermatis. The rami and ringed tubes 

 are extended. 



Fig. 49. The same organs and the oviduct of an adult female of the same species seen from the side ; 

 X 85. This is taken from a specimen which, although adult, was young, i. e. comparatively 

 recently mature. The saeculus foemineus is fuller of spermatocysts than in the last figure, but 

 the ova are very little developed. Tlie arms of the lyrate organ would not descend so much 

 in situ — they would be almost horizontal ; they have been turned slightly downward to show 

 the whole of the saeculus. 



Fig. 50. (Right lower corner.) The same species. One of the tubuli annulati (ringed tubes) seen from 

 the side, x 175, to show the form of the mouth of the tube iu the acetabulum of the third 

 leg. The acetabulum is not shown, only tlie tube. 



Fig. 51. The saeculus loemineus, with its appendages and the lyrate organ, of an adult female Lielaps 

 stabularis, seen from above; x 100. These organs are not quite in situ: the cornu is 

 straightened out to show its whole form ; it would really cuii more round the base of the lyrate 

 organ. A few spermatocysts are seen iu the rami (as after recent coition). 



Fig. 52. (llight margin.) The lyrate organ and ovary of an adult female Hceniogamasus hirsutus 

 (page 303) seen from above; x 85. The camera sjjermatis is seen iu the centre. 



Fig. 53. The saeculus foemineus, with its two great globular diverticula and other appendages, of an 

 adult female of the same species, seen from above; x 75. Drawn from a specimen dissected 

 in very dilute glycerine. The saeculus, cornu, and both diverticula contain numerous spermato- 

 cysts; there are not any in the rami. 



Fig. 54. (Left, near top.) Proximal termination of one of the tubuli annulati of an adult female of the 

 same species in the corresponding ramus, seen from the side ; x 400. The globular termination 

 within the ramus is extremely delicate and hyaline. 



Fig. 55. (Lower left coiner.) Distal termination, or mouth, of the same tube of the same creature, iu 

 the acetabulmu of the leg, seen from the side, to show its form ; x 250. 



