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No: 2.) BLATTA AND DORYPHORA. 295 
description of A/aztta, carelessly written and with figures often 
grossly inaccurate. 
Blochmann’s important paper (5), announcing the discovery 
of polar globules in Alatta germanica and two other insects, 
appeared in 1887. The description of the eggs of Blatta is suc- 
cinct and perfectly accurate. 
Of late, Cholodkowsky (10) has published a preliminary paper 
on the formation of the entoderm in Slatta. 
Doryphora decemlineata has not been investigated heretofore 
from an ontogenetic standpoint. It is surprising that so com- 
mon an insect, and one whose eggs present such advantages for 
embryological study, should have been overlooked. The favored 
Coleopteron of embryologists has always been Hydrophilus, and 
it is certain that the water-beetles (Hydrophilide and Dytis- 
cide) are much less modified forms than the leaf-beetles (Chry- 
somelideé), to which Doryphora belongs. 
Nevertheless the development of several Chrysomelids has 
been studied more or less incompletely. 
Packard (35) made a brief study of Gastrophysa ceruleipennis, 
and Melnikow and Kowalevsky (26) studied Donacza. 
More exhaustive was the attention bestowed on Lzna by 
Graber (15), who published his account in the second volume of 
his text-book on insects (1877). As would be expected from 
their close systematic affinities, Doryphora and Lina differ but 
slightly in their development. 
OVARIES AND OVIPOSITION, 
PBlatta. 
The ovaries of AZ/atta are flattened, broadly spindle-shaped 
masses slung in trabecular connective tissue, continuous with 
the peritoneum. Each ovary consists of from 14 to 26 ovarioles, 
or egg-tubes opening into the oviduct. The latter extends 
backwards towards the median longitudinal axis of the body, 
and after joining the oviduct from the opposite ovary opens into 
the broad and short vagina. Besides the tubular colleterial 
glands the vagina carries on its dorsal face near the proximal 
ends of the oviduct a thick-walled sac, the spermatheca. 
The ovariole has the structure typical in insects. The fol- 
licles in all stages of formation are inclosed by the membrana 
