528 15KITISII ORTRATIDJE. 



and marginal portions of the notogaster are sliglitly 

 raised and rounded, leaving a sliallow depressed line 

 between tliem (this does not apply to the progaster). 

 There are two longitudinal rows of about three setiform 

 hairs each on the notogaster; the pore of the expul- 

 sory vesicle is near the posterior of these. Genital 

 and anal plates close together, the former somewhat 

 broader than the latter, which come almost to a point 

 posteriorly. 



Nymph. 



The nymph is so like the adult that it is not neces- 

 sary to describe it elaborately ; the differences are the 

 softer cuticle without reticulations, the monodactjde 

 claw, and that the abdomen has a number of broad, 

 irregular, more or less transverse wrinkles, which give 

 it an irre ovular outline. 



Distribution. — I have only found a very few speci- 

 mens of this species at the Land's End, Cornwall, on 

 lichen growing on the granite rocks ; it is, however, 

 small and easily missed. 



NOTHRUS MONODACTYLUS,* Sp. nOV. PI. XLY, flgS. 



10—14. 



Average length about "29 mm. 



Average breadth about '19 mm. 



Average length of legs (first and fourth pairs) about 

 •1 mm. 



Average length of legs (second and third pairs) 

 about "08 mm. 



This very small species may be known by the shield- 

 shaped abdomen, short legs, the two hind pairs of 



* MovoQ, aloue; haKrvkoQ, a finger. 



