MANN: ANTS OF THE BRITISH SOLOMON ISLANDS. 385 



furrows. Scutellum a little broader than long, with nearly straight anterior 

 border. Basal portion of epinotum roundly margined at apical half; spines 

 as in worker. Petiole similar to that of worker. 



Feebly shining, with sculpture as in worker. 



Color as in worker. Wings weakly infuscated; veins and pterostigma 

 brown. 



Ugi: Pawa (Type-locality). San Cristoval: Wai-ai, Pamua, 

 Wainoni Bay. 



Closely related to P. ulysses Forel, but distinct in epinotal structure 

 and in the form of the petiolar spines, which are not as long and are 

 very much less divergent than in that species. The thorax is also 

 much more shining in osae than in ulysses. Type. — M. C. Z. 9,191. 



Fig. 56. — Polyrhachis (Myrmatopa) osae Mann. Worker. Petiole from front. 



This species, which is named for Mrs. Osa Martin-Johnson, the 

 first American woman to travel in the Solomons, is a characteristic 

 species of the extreme eastern end of the group. The nests, built on 

 leaves, usually on palm trees, are of carton, strengthened and lined, 

 as well as fastened to the leaf by silk, and are very common objects 

 in the forest. If a leaf bearing a nest is broken off and laid on the 

 ground the ants rush out, but soon enter the nest again and will remain 

 there, even though the nest be placed in a coat pocket and carried. 

 I examined large numbers of nests of this, as well as other species of 

 Polyrhachis, in search of inquilines, wnthout finding any. 



On several occasions I found two dealated females of osae, together 

 with larvae, in very small nests, which indicates that the colonies 

 are sometimes started jointly by more than one queen. 



Nests are shown on Plates 1, 2. 



