ONYCHOPHORA OF WUST AUSTRALIA. 



369 



OCCURRENCE OF THE SPECIMENS OP PERIPATOIDES 

 IN WEST AUSTRALIA. 



It is noteworfcliy that all the specimens of Peripatas taken up 

 to date have been found in the lulls and at some little elevation 

 away from the coastal plains. On the othei- hand they have not 

 been found very far into the interior. They h;ive been found in 

 situations which, at least daring the winter months, are some- 

 what damp but not excessively so. Tliere is no doubt that 

 Peripatus extends over a wide area in West Australia, but it is 

 very difficult to map out this area, for collecting is not exactly an 

 easy task and the animals have their usual eccentric local 

 distribution within it. For ex;imple, the author went out on 

 one occasion to a small valley in the hills where Peripatus w^as 

 believed to occur. An entire morning was spent searching 

 without signs of a specimen, and it was decided that after lunch 

 a new spot should be tried further ahead— the next little valley, 

 in fact. The next valley turned out, however, to be the one 

 where we had imagined ourselves a,ll the morning, and we soon 

 found Peripatus there as on previous occasions. Here were two 

 little valleys only ten minutes ap;U't, with the same vegetation, 

 the same amount of moisture, and presenting such a similar 

 appearance that one had been mistaken for the other. Yet in 

 the one we found many specimens of Peripatus, in the other, 

 none, 



Specimens have up to date been captured at the following 

 places: — -Lion Mill, Mundaring Weir, Armadale, Kelmscott, 

 Kalamunda (all specimens found at these places were supposed 

 to be P. gilesii), and at Tarrahdale and Bridgetown in the S.W. 

 (P.. occiclentalis). 



Most specimens have been obtained at Mundaring Weir, 

 Armadale, and Jarrahdale. At the latter place 13 specimens 

 ' were found under a small piece of branch about 1 foot square, 

 and nearly 150 specimens were captured in three days. Yery 

 few indeed ha ve been found under stones or under bark or fallen 

 trees. The usual place is on the surface of the soil underneath a 

 small or large piece of wood (a fallen branch or part of one). 

 Here the ground is more or less damp and there is no grass. In 

 the same situation white ants are l3y far the most ubiquitous 

 creatures, with nests of true ants frequently lending variety. 

 Large centipedes are often common, but not usually with 

 Peripatus, which prefers, on the whole, the absence of ants, 

 centipedes, and millipedes from its particular sheltering log. 



In the summer no specimens have ever been found and this 

 despite some very arduous work in the broiling sun. Peripatus 

 is, however, extremely sensitive to drought, aiid before the dry 

 season — November or December to April — it must find its way 

 either below the surface of the ground or far into the crannies 

 and cracks in fallen and decaying logs. As the breeding season 

 coincides with the dry season it is impossible to study the 



