Spiders and Their Near Relatives 



It is not as easy to distinguish the sexes of harvestmen as 

 it is those of spiders, where a glance at the palpi is sufficient. 

 With some harvestmen there are no obvious secondary sexual 

 characters; but with most of them the sexes differ in size, coloura- 

 tion, and the proportions of the appendages. Usually the body 

 of the male is smaller and shorter and more brilliantly coloured 

 than that of the female; but the markings of the female are often 

 replaced by a uniform tint in the male. The granulations and 

 spines are usually more marked in the male; and the legs are 

 usually longer. The form of the chelicerae and of the pedipalps 

 often differ in the two sexes, but no general statement can be 

 made of these differences. 



The chelicerae are three-jointed and chelate, the third joint 

 forming the finger of a chela. They are comparatively long and 

 in some forms they are quite stout. The pedipalps are leg-like 

 in form; but are much shorter than the legs; a tarsal claw is usually 

 present; the coxae of the pedipalps bear endites, which are more 

 or less membranous. A similar pair of more or less membranous 

 endites are borne by the coxae of the first pair of legs. These 

 two pairs of endites have been described as two pairs of jaws 

 but in the forms examined by the writer they are hardly fitted 

 for chewing. The legs are very long and slender except that the 

 coxae are stout; but the coxae on account of their fixed condition 

 appear to belong to the body instead of to appendages; the first 

 two pairs of legs bear movable endites in some forms. The tarsi 

 and sometimes other segments of the legs are divided into smaller 

 portions by what are termed false articulations. The tarsal claws 

 vary in number and in form. 



Although the harvestmen have stilt-like legs, they do not 

 raise the body much above the ground when they walk, but carry 

 it low down, with the middle part of their legs high in the air. 

 When disturbed they stand on six legs and move the second 

 pair about in the air; this suggests that perhaps the tips of the 

 second pair of legs are furnished with especially sensitive tactile 

 organs. 



In the North most harvestmen die in the autumn; a single 

 species, Leiobunum formosum, is known to live over the winter 

 as an adult instead of depositing eggs and dying in the autumn, 

 as do the other species (Weed' 89 a). In the South more of them 

 hibernate; they hide under rubbish during the winter. 



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