244 BRITISH TYROGLYPHIDyE. 



pairs are mounted on mammillary elevations, which 

 almost resemble a sixth joint, but are not chitinized. 

 The vulva is placed between the coxse of the fourth pair 

 of legs, and has two pairs of fine hairs anterior to it. 

 The anus nearly touches the posterior margin. 



Male slightly less broad in form than the female, 

 and smaller; the penis is placed between the coxas of 

 the third and fourth pairs of legs ; it lies in a small 

 depression with slightly chitinized edges, and is pro- 

 tected anteriorly by a short, transverse, curved, rod- 

 like sclerite, with a pair of very fine hairs at each end. 

 In other respects, except the absence of the bursa 

 copulatrix, the male practically resembles the female. 



The Hypopial Stage. This only exists in an ex- 

 tremely rudimentary condition; in order to avoid 

 repetition the reader is referred to page 168 for in- 

 formation on this point. The hypopial " case " in this 

 species (PL VIII, fig. 12) is covered with extremely 

 fine vermiform markings (fig. 16), and opens posteriorly 

 by a sort of trap-door (fig. 14). 



Habitat. This species is probably most abundant 

 in houses and buildings upon almost all sorts of dried 

 vegetable and animal matter which is not too hard ; it 

 swarms on hay and fodder in stables ; it is found in 

 great quantities on many vegetable drugs ; it is found 

 on dried insects and on dried fruits. I have known it 

 occur in such quantities in houses on rush furniture, 

 etc., that the occupants have stripped and fumigated 

 the walls and the furniture, and adopted numerous 

 supposed remedies of a chemical nature without suc- 

 ceeding in getting rid of it. Oudemans '* found the 

 same thing on furniture at Assen, the Hague, and 

 Utrecht ; he says that the Acari literally covered the 

 furniture of the whole house, and that they fed on the 

 animal fat which adhered to the not thoroughly cleaned 

 horsehair with which the furniture was stuffed ; he also 

 found it on cork and tobacco. It is also found in the 

 open, but much less commonly. 



* ' List,' p. 251. 



