SCORPIONS, SPIDERS AND CRABS 241 



On further examination of this " excreta " he found that 

 it was really a spider ! Later, when in Sumatra, the same 

 species once more in like manner deceived him. The 

 deception is more than usually remarkable, for it is not 

 due to the coloration of the body, but to what may almost 

 be described as a diabolically ingenious display of intel- 

 hgence. For the creature weaves upon a leaf a small 

 white patch of web exactly resembling the fluid excre- 

 ment of a bird sliding down the smooth surface of the 

 leaf. Having completed this, the weaver lies on its back 

 in the middle of the web holding on by the spines with 

 which the legs are furnished. It then awaits its victim 

 with the disengaged portions of the legs ready to close in 

 a deadly embrace the moment the lure has done its work. 

 Though somewhat in the nature of a digression, these 

 facts show that colour often plays a vital part in well- 

 being ; though in the matter of courtship its role has 

 probably been overestimated. Colour as an aid to " mate- 

 hunting " probably nowhere plays so important a part as 

 was at one time believed. The Warblers among the birds, 

 and the Spiders among more lowly animals, seem to 

 demonstrate this fact. 



The actual mating of Spiders, the act of coition, is 

 peculiar, and demands notice, for the orgasm is not 

 accomplished at the moment of the ejection of the sexual 

 products. The male discharges the seminal fluid upon 

 a small web woven for the purpose, and the liberated 

 spermatozoa are then sucked up into a tube — the 

 receptaculum seminis — which lies coiled up within a hollow 

 bulb attached to the base of the last joint of the leg- 

 Hke feeler, or " pedipalp " at the base of the head. The 

 precious fluid is there stored and retained until the 

 moment arrives when these palps can be thrust into the 



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