ON TRACHEAN ARACHNID A. 513 



each side a small simple eye, placed a little obliquely. 

 Another, but a very small plate, covers the second segment, 

 that one which supports the second pair of feet. The rest of 

 the body is soft, forms an oblong oval, and is composed often 

 rings, which are simply folds of the skin ; the third and fourth 

 serve as an attachment for the four posterior feet. 



These four feet, as well as the preceding two, are united in 

 pairs, at their origin, by means of a common transverse arti- 

 culation, divided in its middle by a depressed line, and cor- 

 responding to the maxillary articulation of the first two feet, 

 and of the palpi. There is no sternum properly so called, the 

 space which occupies its place being taken up by this series 

 of radical articulations. These six feet, the lengths of which 

 augment progressively, present, as usual, those parts which 

 are distinguished by the names of haunch, thigh, leg, and 

 tarsus. The haunch is composed of two very short articula- 

 tions ; the thigh and leg are long, and of a single piece ; the 

 tarsus, more slender, as well as the leg, is divided into three 

 articulations, the first of which is very long, and the last very 

 short ; at the superior extremity of this last are implanted two 

 filiform appendages, arched, hairy, similar to two fingers, and 

 each terminated by a small scaly hook. All these divers arti- 

 culations are cylindrical. 



The feet are bristling with long hairs, and have here and 

 there some small mobile spines. The haunches of the two 

 last have, underneath, a range of small scales, very thin, trans- 

 parent, and composed each of a pedicle, at the end of which 

 is a mobile triangular piece, broad, folded in two, or forming 

 an angle, and inclined in some species. These scales might 

 be compared to one-half of a funnel, compressed, and cut in 

 two, in the direction of its length. They represent, though 

 but very remotely, the combs of the scorpions. The abdomen 

 is oblong, soft, and more or less hairy, as well as the body, 

 and without any appendage, at least any projecting one, at 



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