664 



AC AKIN A. 



Fig. 639. 



the fii-st joint very large, forming a toothed eating surface. 

 The ocelli are nearly obsolete, and the legs have from one to 

 three claws. The cephalothorax has generally two wing-like 

 projections, and two or three cup-shaped 

 pedicellated stigmata on the edge. They 

 generally live on vegetable matter. In 

 Oribates the side of the cephalothorax is 

 produced often into wing-like processes, 

 with the abdomen orbicular, flattened, 

 sometimes emarginate. The European 

 0. alatus Hermann is smooth, blackish 

 brown, and lives under moss. In Notlirus 

 the body is elongated, somewhat quadrangular, and has no 

 lateral expansions, while the legs are stout, with tripartite 

 claws. We have observed an undescribed species of this genus 

 sucking the eggs of the canker-worm in Salem. It may be 

 called Notlirus ovivorus (Fig. God). It is reddish brown, with 

 a dense hard body, with the edge of the abdomen expanded 



evenly, and with three 

 slender capitate processes 

 on the cephalothorax. 



AcARiD^. This family 

 comprises the true mites, 

 which have soft, thin- 

 skinned bodies, with 

 either scissor or style-like 

 mandibles, the latter form- 

 ing a retractile horu}^ 

 tube. The maxillae are 

 obsolete, as well as the 

 ocelli. The claws are 

 sometimes provided with 

 a sucker. The members of this, and the foUowiug gi-oups, 

 are among the most lowly organized of articulates, and are 

 found living parasitically on the skin of other animals, or 

 buried witliin their integuments, while certain acari have 

 been detected within the lungs and air passages, the bloodves- 

 sels and the intestinal canals of vertebrate animals. The 



Fig. 610. 



