510 Mr. R. Shelford’s Studies of the Blattide. 
his specimens and found that it contained a perfect ege- 
cluster of crescentic form, the eggs to the number of forty- 
four and in different stages of development being arranged 
in a double row. The egg-mass was contained in a thin- 
walled prolongation of the genital pouch, which may be 
termed the brood sac. Whilst in most cockroaches the 
egg-capsule is a horny structure, in Panchlora viridis it is 
a fine membranous sheath enclosing only the basal half 
of the egg-mass. The colleterial glands have always been 
regarded as secreting the substance of the horny ootheca 
of blatiide, and Riley assumed that they are absent or 
much reduced in Panchlora viridis but did not test the 
truth of his assumption by dissection. From another 
specimen examined by Riley young larve and nearly 
mature embryoes had been extruded. 
Holmgren in a paper on viviparity amongst insects 
in general (Zool. Jahrb. Syst. xix, p 484,) records vivi- 
parity for three more genera of Blattide, viz. Hustegasta 
micans, Sss. and Zhnt., Oxyhaloa saussuret, Borg, and an 
undetermined species of Slabera. In the latter species 
the developing eggs are contained in a horny and sculp- 
tured capsule which lies in a thin-walled brood-sac and is 
apparently retained there till the eggs are mature or 
nearly so. In Hustegasta micans the ootheca splits open 
whilst still in the brood-sac, and the young larvee emerge 
two by two from the mother. Holmgren divides Blattidx 
into three sections according to their method of repro- 
duction, as follows :— 
1. Oviparous species, which carry the ootheca for some 
days protruding from the tip of the abdomen. 
Ex. Periplaneta. 
2. Viviparous species, the ootheca retained within a 
brood-sac. 
Ex. Hustegasta, Oxyhaloa, Blabera. 
3. Viviparous species, the ootheca practically absent. 
Ex. Panchlora. 
To this last section and possibly to the second I am 
able to add more examples. 
My own attention was specially drawn to this 
phenomenon of viviparity amongst Blattide in rather 
an interesting manner. Whilst arranging the South 
