132 ACARINA. 



tinguished within the body of the female (fig. 36) ; 

 they are oval and granular. 



Another species of Acarus, A. sac'chari, is found 

 abundantly in ordinary moist sugar. If a little of 

 the sugar be placed in a wine-glass, some water added, 

 and the mixture be stirred until the sugar is dissolved, 

 the Acari will be found both in the sediment and 

 floating on the surface. 



A somewhat larger member of the order occurs as 

 a parasite upon a species of Dung-beetle (Geotrupes 

 ster cor arms] which is vulgarly known as the Lousy 

 Watchman. The beetle is black, shaded with 

 purple, about three-quarters of an inch long, and is 

 found under cow-dung. The mites cling pertinaci- 

 ously to the under parts of the beetle, and can easily 

 be seen with the naked eye. They are whitish, with 

 the mandibles, the sucker, and two claws very dis- 

 tinct ; and the palpi are unattached to the labium, 

 or free. These mites form the species Gam'asus 

 coleoptrator'um. Another species, Gamasus teldrim, 

 is the red spider of the greenhouse. 



Trombirfwm fuliginosum (PL IX. fig. 37 d) is a 

 common red spider of gardens. It is of a scarlet 

 colour, appearing velvety from the presence of a dense 

 coat of feathery hairs (fig. 37/) . The palpi of this 

 mite are large, free, the last joint but one (PL IX. 

 fig. 37 a) being furnished with a claw, while the last 

 joint is obtuse, and resembles a lateral appendage. 

 The mandibles (fig. 37 b) are furnished with a sharp 

 curved claw. The legs are long, especially the an- 

 terior pair, and terminated by two claws, with a de- 

 licate sucker-like appendage (fig. 37 c). 



Another species of Trombidium, T. holoseric'eum, 

 greatly resembling the last, is also found in gardens. 

 It may be easily distinguished from the last by the 

 club-shaped hairs (fig. 37 e) existing upon the body. 

 The harvest-bug, which causes such irritation of the 

 legs of persons who frequent corn-fields in the 



