3 1 86 THE JOINTED ANIMALS 



the great width of the carapace, we find the coxae of the third and fourth pairs of 

 legs widely separated, so that there is an oval sternal area, around which the coxae 

 of the five pairs of large cephalothoracic limbs are arranged radially. The anterior 

 and posterior sternal pieces of the preceding suborder are present between the coxae 

 of the first and last pair of legs respectively, and the space between them is filled 

 by horny pieces, varying in the degree of their development. The appendages also- 

 differ from those of the.Uropygi, the basal segments of the pincers being freely 

 movable and not united, while these appendages are longer, thinner, and very 

 spiny. The terminal segment forms a sharp claw, closing back on the penulti- 

 mate segment like the blade of a knife. The legs of the first pair are long and 

 slender, and all its segments, except the first three, are converted into a long, 

 thread-like, many-jointed lash acting as a feeler. The males do not, as a rule, differ 

 strikingly in external characteristics from the females; although the abdomen is 

 narrower, and the pincers and legs are longer. 



In geographical distribution the group resembles the Thelyphonidce , with the 

 exception that it is spread over Africa south of the Sahara, extending from 

 Senegambia and Abyssinia southward into Cape Colony; but there are no species 

 from Madagascar. It also seems to extend in India farther to the west than do the 

 Thelyphonidce, since species occur at Bombay, and thence spread along the south 

 coast of Arabia from Muscat to Aden. In the Indian region the species are not so 

 numerous as the true whip scorpions, and in the Philippines they seem confined to 

 caves, living permanently in the dark. None are known from Japan or China; but 

 in America a few have been recorded from Texas and California, and many from 

 Central America, the West Indies, and South America, as far down as Patagonia. 

 Like the last, this group dates back to the Carboniferous, a single genus, 

 Grceophonus, having been described from the coal measures of North America. A 

 single specimen has also been discovered in the Miocene gypsum beds of Aix. The 

 existing forms may be all included in the family Tarantulidce ; the genera being 

 mainly characterized by the degree of development of the horny pieces on the 

 lower surface of the cephalothorax. In habits the group resembles the last, 

 except that the species, instead of digging burrows, avail themselves of natural 

 , crevices and holes, hiding beneath stones or fallen tree trunks, for which they are 

 adapted by the flatness of their bodies. The species frequenting grottoes in the 

 Philippines cling to the walls, with legs extended, and dart into .rocky fissures at 

 the least disturbance. 



Order PALPIGRADI 



This group is represented only by a single South European form (K&nenia 

 mirabilis). Structurally, this minute creature occupies a position intermediate 

 between the whip scorpions and the Solifugce. As in the Thelyphonidce, there is a 

 long, jointed tail, articulated to the last abdominal segment, which with the two 

 that precede it, is narrowed to form a movable stalk; but, as in the Solifugce^ the 

 abdomen consists of only ten segments. The carapace is segmented and has no 



