92 
Psyche 
[June 
The flanges of the oothecae of the subgenus Arenivaga (Figs. 21-23) 
are considerably shorter than the flanges of the subgenus Psammo- 
blatta (Figs. 17,19) or of Polyphaga aegyptiacci (Fig. 18), and sug- 
gest that within the Polyphagidae there has been a reduction in the 
length of the flange. According to McKittrick (1964) the oothecae 
of some of the more primitive Plectopterinae still have a flange. 
Since rotation is defined as a reorientation or turning of the ootheca 
90° so that the keel faces laterally, I consider the manner in which 
Arenivaga (Arenivaga) spp. carry their egg cases prior to depositing 
them, as true rotation. However, this may be considered to be a 
primitive type of rotation because none of the eggs are enclosed or 
hidden within the vestibulum of the female after the egg case is 
turned 90°. The polyphagid Therea petiveriana (Linnaeus) also 
rotates its ootheca (Figs. 15,16) prior to depositing it, as figured by 
Ananthasubramanian and Ananthakrishnan (1959). Because of the 
supra-anal plate, it appears as though some of the anterior eggs are 
within the vestibulum of the female (Fig. 15). However^ when 
viewed ventrally (Fig. 16) one can see that none of the eggs are 
hidden inside the female. The flattened upper anterior corner of 
the ootheca (Fig. 24) is the only part held by the female. McKittrick 
(1964) claims that the polyphagid Hypercompsa fieberi (Brunner) 
does not rotate its ootheca. However, she (personal communication) 
based this conclusion on a preserved female that was carrying a fully 
formed ootheca with the keel upright. This female may have been 
preserved prior to rotating the ootheca and a definite conclusion as 
to whether or not the Holocompsinae rotate the ootheca must await 
study of additional material. 
Bey-Bienko (1950) erected three subgenera of Arenivaga; he be- 
lieved that the subgenus Arenivaga (restricted in distribution to the 
deserts of the southwestern part of North America and with one 
species peculiar to the peninsula of Florida) is very close to and is an 
unquestioned derivative of the subgenus Psammoblatta, but is more 
specialized than the latter. The method of oviposition (i.e., rotation) 
tends to support Bey-Bienko’s conclusion that A, (Arenivaga) is 
more advanced than A. (Psammoblatta) . The Polyphagidae need 
revision, using characters studied by McKittrick (1964). I sent 
specimens of Arenivaga (Psammoblatta) cerverae to McKittrick, 
and she believes that it is not an Arenivaga and does not think it 
belongs in the Polyphaginae (where she includes Arenivaga (Areni- 
vaga) spp.). She wrote (personal communication) that A. (P.) 
cerverae is close to the Polyphaginae; the female genitalia “. . . are 
in general arranged like those of Arenivaga ( A .) bolliana, and A. 
