14 Transactions of the Society. 



eggs mature are shown at plate II. figs. 6 and l,h; their size then is 

 quite disproportionate to that when the eggs are still in the ovary. 

 The whole oviduct is greatly expanded, and each eg^ is lodged in a 

 pocket, or chamher, formed by the distension of the elastic walls of 

 the duct, and the flattening of the corrugations. This chamber 

 usually follows the egg in its progress along the duct ; in Damseus 

 geniculatus, and probably in some other species, the earlier cham- 

 bers do not appear to follow, or to subside after the passage of the 

 egg, but persist to some extent ; this may be due to the egg remain- 

 ing an unusual time there while acquiring its chitinous shell. 



In Orihata ghhula, Dameeus geniculatus, and some other species, 

 there is, on each side of the central ovary, and joined to it by a 

 short portion of the oviduct, which is of equal length on each side, 

 an almost globular extension of the oviduct, containing a globular 

 body, which has the appearance of an ovum which has not yet 

 assumed the oval form or the chitinous shell, and which almost 

 entirely fills the chamber ; these, like the central ovary, are 

 developed when the creature first emerges from the nymph al skin, 

 and while the other portions of the oviducts are unexpanded and 

 empty. Both the central ovary, and certain large cells lying on or 

 in the exterior walls of the two globular extensions, where the 

 latter exist, stain deeply with logwood, &c., whereas the other 

 portions of the oviduct scarcely take the stain at all. Whether 

 these globular chambers be simply uterine, each containing an 

 ovum, which here attains full size, or whether they are, or also 

 function as, spermathec«, or glands secreting a vitelline substance, 

 or one destined to form the egg-shell, is a question which I have 

 not been able to decide to my own satisfaction ; some light may be 

 thrown on the question of whether they function as spermathecae 

 when we know how copulation takes place, a matter which is not 

 recorded, and which I have not succeeded in ascertaining ; but it is 

 certain that in Damieus geniculatus, the egg of which has a very 

 hard chitinous shell, and other species having this globular enlarge- 

 ment, the eggs in the ovary, and between it and the globular body, 

 are small, white, and soft, and show large clear nuclei and one or 

 more round, distinct nucleoli, yelk-division not having more than 

 commenced, even if it has commenced at all ; but that, immediately 

 they have passed thLs point, they have attained their full size, and 

 the shell has become harder and darker, and yelk-division has 

 largely progressed. This would seem to indicate that the globular 

 body is an ovum and the enlargement a special point in the duct 

 functioning as a uterus in these species. The only difficulty of this 

 view would seem to be that the globular expansions, presenting 

 similar appearance, are present in specimens just emerged, which 

 have not any other eggs in the duct. A portion of the ovary with 

 the part of one oviduct up to and including the globular chamber, 

 is shown filled with eggs at plate II. fig. 8. 



