Falconey : Notes on Harvest-Spiders. 217 



much smaller size often attack them. One of these assailants, 

 the youngf six-legg'ed form of a red mite, one of the Tronibidiice, 

 attaches itself g-enerally to their leg's, but occasionally to the 

 upper and lower surfaces of their bodies, selecting" those situa- 

 tions which are out of reach of its victims. Being at this 

 stage of its existence a true parasite, its intention, in thus 

 effecting a lodgment on another animal, is manifest. Firmly 

 anchored in this position by peculiar modifications of the mouth 

 parts, it is enabled to suck the juices of its host, and at the same 

 time secure wide dissemination. Eventually it drops to the 

 g"round, in which it hides itself, changing in about three weeks 

 into the perfect eight-limbed free imago. Harvestmen, 

 especially when, as often happens, they carry several of these 

 mites at once, are, owing to the bright colour of the latter, 

 rendered much more conspicuous objects than from their sober 

 colouring they would otherwise be. Sometimes too, as has 

 often been observed in England * and in Germany,! the pseudo- 

 scorpion takes advantage of the free-roaming harvestman's long 

 legs as a means of locomotion, holding firmly by its strong pincers. 

 Its motive is much less obvious than that of the mite, and con- 

 sequently, naturalists who have enquired into the reason for this 

 strange habit, have not all come to the same conclusion. Some 

 think it merely desires a change of quarters, and adopts this 

 plan to attain its end ; some that being disturbed in its lair, and 

 being moreover of a very pugnacious and obstinate disposition, 

 it angrily seizes the intruding limb, will not let g^o, and is, 

 therefore, taking an involuntary ride. Mr. H. Wallis Kew, in 

 an interesting article, J concludes that the pseudo-scorpion, in 

 spite of its vastly inferior size, attacks other creatures for food, 

 and must therefore be regarded as an animal of prey ; he adduces 

 observations from various sources in support of his view, but 

 adm.its the subject will bear further investigation. Apparently 

 the harvestman does not (one wonders why ?) associate violence 

 with the treacherous attacks of the parasitical mite or predacious 

 pseudo-scorpion, and makes no attempt to clear itself of them by 

 throwing off" the infested limb. 



The twenty-five species (of which one is doubtful) of British 

 harvestmen are arranged in three families and nine genera, and 

 all belong to the section Plagiostethi of the Order Opiliones 

 '^\.w\A.= Pluilangidea Cb. While the different species are not 



* Rev. \V. W. Spicer, ' Science Gossip,' 1867, p. 244. 



4. Professor Leydig-, ' Skizze zu einer Fauna Tubingensis,' 1867. 



:J: ' Natiu-alist,' July, 1901, No. 534, pp. 195-215. 



1906 July I. 



