STRIDULATION IN SOME AFRICAN SPIDERS. 19 
distinct stridulation may be easily produced artificially by rubbing 
| the leg and palp together, the long “notes” on the coxa of the 
first leg giving rise to a distinct “click, click” when scraped 
| against the spines on the maxilla; while the spines on the 
trochanter of the first leg, when rubbed against the stiff brush of 
_ hairs on the trochanter of the palp, gives out a sound resembling 
_ the rustling of a silk dress. 
But what is to be said respecting the function of these 
| organs, and what evidence, it may be asked, can be adduced in 
| support of the view that they subserve stridulation? To this 
| question the answer must be that so far as the African species 
| are concerned there is no direct evidence based upon observation 
| of the living animal to show what part they play in the Spider’s 
| economy. But that their true and probably sole function is the 
| emission of sound, as has been claimed in the preceding pages, 
|is so strongly supported as to reach practical certainty from what 
'is known of the function of the analogous organ detected by 
| Wood-Mason in the Assamese genus Musagetes. 
| Mr. Peal, it appears, was the first to notice the phenomenon. 
| His gardener, while engaged in digging up a field, unearthed one 
‘of these great Spiders, and, not being a collector, naturally 
| enough proceeded to strike at it with his hoe, with the object of 
ridding the world of such vermin. Thereupon the Spider raised 
| itself upon its two pairs of hind legs, brandished the two 
| remaining pairs in the air, opened its jaws, and waved its palpi 
up and down, scraping the basal segment to and fro against the 
| outer surface of the mandible, and emitting a sound subsequently 
described by Wood-Mason as resembling that produced by 
rapidly dropping shot on a china plate. Fortunately Mr. Peal 
rescued this historic Spider from the gardener, and afterwards 
| had the satisfaction of seeing it repeat the performance when 
attacked by a cat. In confirmation of this story, it may be 
jadded that Mr. EK. W. Pickard-Cambridge told me recently, in 
course of conversation, that one day, when leaving his bungalow 
| at Coremia in Assam, he met one of these Spiders coming up the 
steps, and on his approach the beast reared itself up, waved its 
| legs, and hissed at him. And lastly, Prof. Baldwin-Spencer has 
|made similar observations upon an allied genus Phlogius, observed 
by him in Australia, his account being accompanied by a beauti- 
| c2 
