Genera and Species of Blattide. 165 
latter genus have the pronotum well adapted for digging, but 
others have not, and it would be of the greatest interest to 
learn if the habits of the species vary in correlation with the 
form of the pronotum. 
Bantua is intermediate in structure between Cyrtotréa and 
Derocalymma ; some specimens collected by Dr. Longstaff in 
S. Africa were taken from beneath a log, which means, I 
expect, that they were lurking in the rubbish immediately 
surrounding the log, as they are not adapted, like Dero- 
calymma, for life beneath a heavy body, judging by their 
facies. 
Finally, the question arises, has Derocalymma originated 
from a form like Pilema, passing in the course of its evolution 
through a Bantua-like stage? One is tempted to answer in 
the affirmative, for adaptation to life beneath stones could 
have been brought about by mere flattening of a generalized 
type of cockroach with a simple form of pronotum, as has 
indeed occurred in the Australian genus Uniscosoma, super- 
ficially similar to Derocalymma, “but structurally widely 
different. The highly modified pronotum of Derocalymma 
has resulted from the flattening not of a simple form of pro- 
notum, but of a complex form with lateral bands; the lateral 
bands in Pilema are the most essential parts of the exca- 
vating organ, the pronotum; but they can serve no useful 
purpose in species that do not burrow into the ground, and 
the manner of their modification in response to a different 
habit of life is shown in the genus Bantua, and especially in 
the new species of that genus described below, the final step 
in the process being exhibited by Derocalymma. 
Genus BANTUA, nov. 
Cyrtotria, Saussure and Zehntner (nec Stal), Rev. Suisse Zool. iii. p. 28 
(1895). 
Differs from Pilema, Sauss., and Cyrtotria, Stal, in the 
form of the pronotum, the lateral bands being bent under the 
disk and forming an acute angle with it; the margin of the 
pronotal disk forms the outer margin of the pronotum. In 
the female the posterior angles of the pronotum are more or 
less produced backwards. Differs from the genus Dero- 
calymma, Burm., by the less complete bending under of the 
lateral bands cf the pronotum, by the eeaincaode tegmina 
of the male, and the backwardly produced posterior angles of 
the pronotum in the female. 
‘Type of genus. 2 erispheert ia dispar, Burm, 
