526 SUPPLEMENT 



having mandibles and palpi ; and from the phoxichili, because 

 their mandibles are forceps-like or didactylous. 



The nymphons are, of all the pycnogonides, those whose 

 body and feet are most slender and most long. They also 

 diflfer in the form of the first articulation of the body, which 

 may be considered as the head : it is proportionally longer, 

 and more narrowed in the middle. The sucker is cylindrical, 

 which is likewise the case with the phoxichili, but not with 

 the pycnogona, when this part has the form of an elongated 

 cone, and truncated at the point. The two neighbouring feet 

 in the females have two intermediate articulations, much 

 longer than the others, and curved. The external and general 

 organization of the nymphons, being otherwise similar to that 

 of the other arachnida of the same family, it would be super- 

 fluous to dilate upon it here. Of their history nothing parti- 

 cular is known. 



In the third family of Trachean Arachnida, that of HoLE- 

 TRA, we have now to treat of the genus Phalangium. 



The phalangia are very remarkable for the length of their 

 feet. The first naturalists who wrote upon these insects called 

 them long-legged spiders ; but they differ from the spiders, 

 not only in their internal organization, but also with respect 

 to the general form of the body, the number of the eyes, the 

 parts of the mouth, and the mode of living. They are to be 

 seen every where. In the country they may be found upon 

 plants, and also are observed in houses, upon plastered walls, 

 to which they are fond of hooking themselves. 



Their body is ovoid or rounded, often depressed, and 

 enclosed beneath a skin slightly coriaceous. Their corslet, 

 the anterior of which is angular, and which is about one-third 

 and a half of the length of the body, is separated from the 

 abdomen only by a transverse line. This abdomen is covered 

 with a skin of a single piece, forming several folds, which 

 mark the rings. It has a stigma on each side, near the origin 



