399 



dermapterous types or exhibited peculiarities such as are found, 

 for instance, in Hemimerns, and (3) the occurrence of Arixenia 

 in the breast-pouch of the naked bat was accidental or whether 

 there existed really such a close association between this insect 

 and the bat. 



Several more examples of the naked bat (in alcohol) were 

 examined and instructions sent to some naturalists residing in 

 the Malayan countries, all without result. You can imagine 

 the pleasure it gave us when last winter [i.e. winter 1911-12) 

 Burr received from E. Jacobson a consignment of Dermaptera 

 which turned out to consist of adult and immature examples of 

 a species of Arixenia. Herr E. Jacobson, on being told of 

 the great interest attaching to the specimens, sent a report on 

 his captures and very kindly put a large number of specimens 

 in alcohol and some pinned ones at our disposal, ^^'e had hoped 

 that he would be able to attend the Congress, and to give per- 

 sonally an account of his discover}', but he had to return to Java 

 before the date of the Congress, not without promising, however, 

 that he would again visit the place where he found Arixenia, and, 

 if possible, provide us with all the stages of growth in a suffi- 

 ciently good state of preservation for a more minute anatomical 

 examination than the present, more or less decayed, specimens 

 will admit. 



E. Jacobson gave us the following report on his captures : 



" This remarkable species (of which I am sending you thirty- 

 five specimens besides a number of damaged ones) was found by 

 me in a cave near the sea-shore at Babakan (Banjoumas Resi- 

 dency, Java). The cave is called by the natives Gouica Lawa, 

 which means bat-cave, on account of the tremendous number of 

 bats which frequent it. The cave is a narrow cleft in the rocks, 

 about forty to fifty metres deep and of about the same height. The 

 floor is covered with a thick layer of guano from the bats. This 

 accumulation of excrements serves as food to a large number 

 of insects. The mass is all alive with the larvae of beetles and 

 flies, more particularly a kind of Trox and dift'erent species of 

 Tenehrionidce. The curious caterpillar of a moth, carrying its 

 own cocoon, which has the shape of a mussel, is found there in 

 great numbers. 



"The most conspicuous insects inhabiting the cavern are. 



