ACAEINA 



441 



A, male 



s pa 



; B, 



female. 



and the back 2 pairs of legs; mandibles usually chelate and beneath an 

 epistome; legs with 5 joints and with a terminal sucker; in some genera 

 the male has a pair of clasping suckers and copulatory legs; abdomen 

 often bilobed behind: 31 genera and 400 species, which live upon birds, 

 feeding on the feathers, epidermal scales, etc., and usually not parasites; 

 24 American species. 



1. ANALGES Nitzsch (Dermaleichus Koch). Body elongate, with the 

 hinder end rounded or pointed, and 



never deeply bilobed; spines on the 

 first pair of legs; third pair of legs 

 of male larger than the others and 

 ending with claws and not suckers; 

 basal joint of first and second leg with 

 a backward projection: on singing 

 birds; 23 species, American. 



A. passerinus (L.) (Fig. 694). 

 Length .45 mm. ; third pair of legs of 

 male enormously enlarged and used as 

 claspers: a European mite, found on 

 several species of American birds. 



2. MEGNINIA Berlese. Third pair 



of legs much larger than the fourth, with long spines on the terminal 

 joint; end of abdomen deeply bilobed in male: 42 species, 6 American. 

 M. columbae Buchholz. Length .33 mm.; each abdominal lobe in 

 male with 2 long and several small bristles; space between the lobes 

 filled in by a membrane: on domestic pigeons and other birds. 



FAMILY 5. TYROGLYPHIDAE.* 



Minute mites with an elongated body and a smooth integument; legs 

 alike in the two sexes; mandibles usually chelate; eyes and tracheae 

 absent; pedipalps close against the mouth parts; young born with 3 

 pairs of legs, in most forms passing through a stage called the hypopus, 

 in which it has 8 legs, but no mouth and no distinct mouth parts, but 

 with suckers on the under surface, which enable it to attach itself to 

 some insect or other animal which will transport it to some new local- 

 ity, where it completes its metamorphosis: about 47 species, 27 species 

 being American; they are not parasitic, but live on dried or decaying 

 animal and plant substances, but are often a pest to housekeepers, gar- 

 deners, and grocers, especially as the hypopus is often spread by 

 house flies. 



* See "A Revision of the Tyroglyphidae of the United States," by N. Banks, Tech. 

 r. No. 13. Bur. of Ent., Dept. of Ag., Washington, 1906. 



