Injurious to Man. 19 



legs composed of five segments and apparently without hairs. 

 The total length of the body was ■ 55 mm. I propose the name 

 hominis for this species of Cytoleichus. 



Another species (G. banks i) has recently been discovered by 

 Wellman on squirrels in California. 



Genus — Chorioptes, Gerv. 

 Chorioptes bovis, Gerlach. 



Chorioptes bovis is a parasite causing a localized skin-disease in 

 cattle, but this complaint is not very grave and extends but slowly. 



Most authorities are of opinion that this mite does not attack 

 man, but Ziirn states that he has found it on the head of a man 

 affected with alopecia. 



Genus — Psoroptes, Gervais. 



The mites of the genus Psoroptes can easily be recognized by 

 the long three- jointed pedicel of the tarsi. They are the cause of 

 Psoroptic Mange in cattle, horses, sheep, etc. 



Leslie Linzell, of the Divisional Veterinary Hospital at St. 

 Albans, who has spent much time in studying parasitic mange in 

 horses and is well acquainted with the different species of Acari 

 infesting these animals, informs me that he has been attacked 

 more than once by the Psoroptes of the horse (P. equi, Hering) 

 whilst attending to horses suffering from the mange caused by this 

 species of mite. The irritation set up by the bite of Psoroptes 

 equi was severe, but transient in nature, for all the ill effects had 

 disappeared the day after the attack. 



It is stated by most authorities, however, that P. equi only 

 attacks the horse, ass and mule, and cannot be transmitted to 

 other animals. 



Family— TYBOGLYPHIDAE. 



The Tyroglyphid mites are minute soft-bodied species ; the 

 cheese-mite (Tyroglyphus siro, Linnaeus) and the flour-mite 

 (Aleurobius farinae, De Geer) are familiar examples of this family. 

 These mites are closely allied to the Sarcoptidae, and, like the 

 Acari of that family, they are without tracheae or stigmata. 



Mites of the genus Glycyphagus sometimes swarm in raw sugar, 

 and formerly grocers and others handling this product used to be 

 troubled by a slight irritation of the skin caused by the mites. 



c 2 



