LENGTH OF OOCYTES (MM) 
203 
1964] Roth — Reproduction in Cockroaches 
DAYS AFTER OPPOSITION 
4 ^ 
Fig. 4. Effect of distention of the uterus on inhibition of the corpora 
allata during late gestation in N . cinerea. Solid circles = Carrying oothecae 
(controls). Ten to 18 females (N — 143) used for each point. Open circles 
= Oothecae removed 30-31 days after oviposition ; no tube inserted in 
uteri. Ten females (N = 100) used for each point. The average time 
required to oviposit again, when the oothecae were removed at 31 - 32 days 
of pregnancy, was 12 days (fig. 2) or 43 -44 days after the initial ovi- 
posit'on. Solid squares = Oothecae removed from females 30 - 31 days after 
oviposition and glass tubes (4.1 - 4.3 mm. X 10-11 mm.) inserted in the 
uteri. Five to 16 females (N = 92) used for each point. Vertical bars are 
one standard error but only one-half the error is indicated where they 
overlapped; no bars indicate standard errors of ± 0.02 mm. or less. 
cease earlier in some females with glass inserts than in females carry- 
ing oothecae (fig. 3). 
The effect of different degrees of uterine stretching, using glass 
rods, and glass beads of 3 different diameters, was investigated in 
