;320 



abdomen more or less cylindrical ; external genitalia large, the 

 valves produced at apex into an obtuse point. 



Key to the Species. 



\. Length over 2 mm. 



a. Scape of the antenna) very long, extending 



beyond the top of the head by more 



than half its length P. longipes, p. 320. 



b. Scape of the antennae short, extending 



very little beyond the top of the head. 

 '. Ocelli present. 



a-. Clypeus with a median vertical 



carina. 

 rt 3 . Basal two abdominal segments 



densely pubescent, opaque P. moclleri, p. 321. 



I*. Basal two abdominal segments 



sparsely pubescent, shining P. wrougktoni, p. 321. 



b-. Clypeus not carinate, convex P. ruthneyi, p. 322. 



b'. Ocelli absent P. watsotti, p. 322. 



1J. Length under 2 mm. 



a. Colour pale dull brownish yellow. 



a'. Head, thorax and abdomen punctured . P. e.viffua, p. 323. 

 b'. Head, thorax and abdomen smooth, 



not punctured P. dichroa, p. 323. 



b. Colour black or dark chestnut-brown. 

 a'. Frontal area distinct, well-defined. 



a 2 . Head striate, opaque P. ruyeri, p. 324. 



b-. Head smooth, polished and shining . P. jerdoni, p. 324. 

 b'. Frontal area indistinct, not well-defined. P. pissinn, p. 324. 



:J01 . Plagiolepis longipes, Jenhu (Formica), Madi: Jaiir. L. $ ti. 

 xvii (18.51), p. 122, ; Forel, Jour, liornb. N. H. Soc. viii 

 (1894), p. 414, $ . 



% . From pale honey-yellow to a light orange-yellow, antennae 

 and legs a shade paler, abdomen above with a tinge of brown ; 

 head, thorax and abdomen very minutely and closely reticulate 



Fig. 97. Plagiolepis longipct, . 



punctate, but shining, covered with a few scattered erect yellow 

 hairs; pubescence wanting. Head oval, very rounded posteriorly; 



