104 
Psyche 
[June 
The structure of the ootheca and ovaries, as well as oviposition 
behavior of Lophoblatta brevis indicate that, with the exception of 
rotation of the ootheca, reproduction in the Plectopterinae has evolved 
along the same general pathway as that which occurred in the Blat- 
tellinae. However, at the time of oviposition, most plectopterine 
oothecae have <50% water^ whereas the Blattellinae have >50% 
water. Although the water uptake curve of the plectopterine L. brevis 
can be used as an example to link the oviparous Blattellidae with the 
ovoviviparous Blaberidae, it is likely that ovoviviparity arose from 
a Blattellinae-like form because rotation of the ootheca was a pre- 
adaptation necessary for the evolution of the Blaberidae (Roth, 
1967b). Because the initial water content of the oothecae of prac- 
tically all Blattellinae examined have been found to be more than 
50%, I suggested that viviparity (in the only viviparous species 
known, Diploptera punctata (Esch.) the eggs initially contain about 
65% water) arose from a blattelline stock and Blattella spp. was an 
important Jink between oviparous and viviparous forms (Roth, 
Figs. 9-10. Dorsal and ventral views of a female of Lophoblatta brevis, 
carrying an ootheca (line = 2 mm.). 
