22 Transactions of the South African Philosophical Society. 



be detected. This insect seems very rare ; I found only two or three 

 specimens last year, and four or five this year. 



The second species, Beicheia promontorii, Per., belongs to a 

 genus known to occur in the South of France, Sicily, Algeria, 

 Styria, Herzegovinia, and Carynthia, in caves. I found this new 

 South African species at Newlands on the slopes of the Devil's Peak, 

 in sifting dead oak-leaves ; it was fairly abundant. 



Beicheia promontorii is not entirely blind ; close to the insertion of 

 antennae is a small, black protuberance, which under a high magnify- 

 ing power proves to contain a very small and rudimentary eye con- 

 sisting of only one very convex facet, the diameter of which is 

 y^o of a millimetre. The colour is darker than Scotodipnus, but still 

 amber-like and not darker than in most of the true subterranean, 

 cave-inhabiting beetles. I kept it alive so as to ascertain whether 

 it was blind or not. Placed on a sheet of white paper, surrounded 

 by a small barrier which it would have been very easy for the 

 insect to surmount, Beicheia went straight forward, and quickly, 

 until the antennae came in contact with the obstacles ; it would then 

 stop, the antennae vibrating quickly to try and ascertain what the 

 barrier was. It would then go literally always in touch with the 

 obstacle, as if it was hoping to find an aperture by means of 

 which it would escape. This goes to show that the rudimentary 

 eye is of very little use, if of any use at all. 



It is now proved that subterranean forms occur in South Africa, 

 and the wish so judiciously expressed by Dr. Marloth has been, 

 or was already, partly fulfilled. 



It is of interest to find that these subterranean insects show such 

 a decided affinity to the European ones. 



It cannot be said that Scotodipnus and Beicheia, through a 

 special modus vivendi, similar to that obtaining in Europe, have 

 been affected in their evolution, because both species have been 

 found together with other minute beetles, decidedly peculiar to 

 the Cape and quite characteristic of a fauna which is perhaps one 

 of the best defined and most isolated, so far as we now know — and 

 a good deal is known — in the world. 



In South Europe and Algeria, so far as my experience goes, 

 these insects live by themselves under very big stones where 

 no other insects are found ; at the Cape they are found under 

 comparatively small stones and together with other insects. 



This peculiarity of an isolated Cape entomological fauna has 

 been already proved many times, and the best proof of it is 

 afforded by the entomological collections of the South African 

 Museum, which- — I have no hesitation in saying it — are, so far as 

 South Africa, is concerned, the best and most extensive in the world. 



