10 
Psyche 
[March 
would certainly be unnecessary, if not actually impractical 
here. 
One of the largest oothecae I have seen contained 45 eggs 
and measured 8 x 35 mm., while an unusually small one 
containing 23, probably from an old female, measured 4 x 
16 mm. The average number of eggs found in 14 oothecae 
was 36.4. Saupe (1929) gave an average of 23.25 eggs for 
8 oothecae, ranging from 11 to 38 per ootheca in B. fusca. 
Stewart (1925) reported an ootheca 14 . x IV 2 inches con- 
taining 44 eggs from a specimen of B. ciibensis Saussure. 
(Rehn and Hebard (1927) refer this species to B. discoidal- 
is Serville.) Two oothecae of the Central American B. 
trapezoideus Burm. measured 7 x 35 and 4.5 x 31 mm., 
and contained 40 and 41 eggs respectively. Diploptera, 
which has been more thoroughly studied than any of the 
viviparous roaches, exhibits a pseudoplacental type of vivi- 
parity and forms an ootheca normally containing but 12 
eggs. All other known viviparous roaches produce many 
more eggs at a time, the numbers per ootheca generally 
falling within the limits reported for these three species 
of Blaberus. 
While in the brood sac, all the eggs in an ootheca have 
the micropylar ends directed toward the left. The smallest 
eggs found in newly formed oothecae measured 1.7 - 2.0 x 
4.5 - 5.0 mm. ; the largest, shortly before hatching, 2.5 x 8.2 
mm. In the young germ band stage the pleuropodia re- 
semble short, thick-stalked, immature mushrooms, and pro- 
ject back to the posterior margin of the second abdominal 
segment. In the chitinized embryo, shortly before they are 
resorbed, they appear as long, thin-stalked mushrooms ex- 
tending to the middle of the third abdominal segment. 
They consist of a base and bulb only; there is no evidence 
of any pleuropodial extension as found in Diploptera. The 
eggs contain a large amount of yolk, and a considerable 
amount is present shortly before hatching. In the absence 
of any embryological studies on Blaberus, little more can 
be said concerning embryonic nutrition ; it does not seem 
likely that the mother provides any more than the original 
yolk. 
Many times I have seen females with a newly formed 
