390 Bulletin American Museum of Natural History. [Vol. XXI, 



Prenolepis Mayr. 



54. P. imparls (Say) Emery. — Caldwell (Cresson) ; Camden Co. 

 (Fox); Halifax (Wheeler). 



This is the largest and most widely distributed of the North 

 American species of the genus. It prefers to nest in shady oak 

 woods in soil containing more or less clay. It is almost never found 

 nesting under stones but forms small circular craters consisting of 

 earthen pellets. The workers visit trees for the purpose of feeding on 



the excretions of 

 the extrafioral 

 n e ctaries. I 

 have seen them 

 eagerly licking 

 these organs on 

 the leaves of 

 Ailanthus glan- 

 dulosus. After 

 imbibing these 

 liquids the gas- 



Fig. I. — A outer, B median, and C inner genital valve of male Prenolepis 

 imparis Say. 



ter often be- 

 comes so d i s - 



tended that it 

 is four or five times its normal size and the elegant gait of the insect 

 becomes an awkward waddle. In this replete condition the P. im.- 

 paris worker may be said to represent a temporary stage of the more 

 extraordinary development of the gaster seen in the honey-ants 

 (Myrmecocystus) . The males and females of P. imparis often pass 

 the winter in the parental nest and celebrate their nuptial flight in 

 the spring. 



55. P. imparis var. testacea Emery. — Clementon (Viereck) ; Med- 

 ford (Viereck); Lakehurst (Davis and Wheeler). 



A pale variety which nests only in sandy regions and on this ac- 

 count is the only form of the species to be found in localities like the 

 pine barrens. It is exceedingly common at Lakehurst but seems to 

 be somewhat nocturnal in its habits. Once only during the daytime 

 have I seen the workers leaving the nest in a file to visit some Aphides 

 on a neighboring oak. They readily assume the replete condition, 

 and owing to their yellowish color resemble the honey-ants even more 

 closely than do the workers of the typical form. 



56. P. parvula Mayr. — Atco (Viereck); Clementon (Viereck); 



