76 THE entomologist's recoed. . 



particular part of the cave, not far distant from a place where the roof 

 had collapsed, admitting a certain amount of light and offering an 

 easy egress. 



The walls of the same cavern were hidden in places by dense 

 crowds of a species of Blatta ; the wingless females and larvas of a 

 Perlsphaeria mined in the bats' guano, the winged males mingling 

 with the larger species on the wall. Thousands of small Stcnopelma- 

 tidae leapt about on the floor, and sat where they could find unoccu- 

 pied room on the walls. All these appeared to feed on bats' dung, and 

 the Locustids were the prey of enormous Pedipalpi, which crawled in the 

 open cave, groping for their food all round them with their feeler-legs 

 crossed over their backs. Outside the caves, the smaller, more lightly 

 built, cockroaches, were mostly diurnal, flitting about in the clearings 

 and the sunnier reaches of the jungle. The common house cockroach 

 of the country is Feriplaneta australasiae. Large colonies of this 

 species conceal themselves in the hollows of the bamboos of which a 

 Malay house is principally built. But the most powerful forms, such 

 as PancstJiia, are hidden during the day in fallen trees and branches, 

 into the rotten parts and crevices of which the difi'erent species of 

 this genus are well adapted to insinuate themselves, by reason of the 

 pushing power of their spiny hind legs, which are so strong that it is 

 extremely difficult to hold the insects between the finger and thumb. 

 On one occasion I found a specimen, -pi-ohnhlj P. javanica, in a rounded 

 chamber in the very centre of a great log, with several small white 

 cockroaches crawling round it. The large individual seemed to be 

 healthy, but only the jagged stumps of its wings remained ; it is 

 probable that the others had eaten them off. The colourless speci- 

 mens were not all of the same size, and possibly they were immature 

 forms of the same species as the other. Some large specimens in 

 the Hope Collection at Oxford appear to have lost their wings quite 

 as completely, only the same jagged edge remaining, but there is no 

 information in their case as to hoAV the mutilation came about. A 

 number of forms, belonging to different genera of the Malay Blattidac, 

 bear a more or less marked resemblance to wood-lice, and some may 

 even be mistaken for the Crustaceans. As a rule, such forms are 

 found among dead leaves or under stones, in places which the wood-lice 

 also frequent. I do not believe, however, that this resemblance is 

 mimetic, for it is hard to see how mimicry could benefit either party, 

 or both, in this case ; it seems rather to be adaptive ; wood-louse and 

 cockroach, living under the same conditions, have developed the same 

 general shape of body. The cockroaches, however, which had the most 

 surprising habits of those which came under my notice, Avere certain 

 aquatic forms belonging to the genus Epilampra. While Ave Avere staying 

 in a hill-clearing on the boundary of the States of NaAA'nchik and 

 Jalor, the gelatine on some photographic plates, Avhich Avere left to dry 

 in a small hut built OA^er the stream, Avas eaten aAvay during the night. 

 Our Malay servants assured me that the damage had been done by 

 " lipas ayer," or Avater-cockroaches, but I did not believe them. A fcAV 

 days later one of them pointed out to me a cockroach craAvling along 

 the sandy bottom of a small mountain rivulet, and afterAvards I secured 

 specimens both from a jungle burn in Ehaman and from the Kelantan 

 river. In the river the Avingiess females sit on floating logs, in the 

 crevices of Avhich they deposit their egg-capsules, just aboA'e the water- 



