ANTS. 



an arid region where moisture and food arc precious, and the storing 

 of honey in replete workers, in turn, is possible only in very dry soil. 



Prenolepis iinparis would seem to be an exception to the general 

 rule of distribution in the honey ants, since the typical form of this 



>pecies occurs in rather shady places and 

 in clayey soil which holds moisture rather 

 tenaciously. It is not improbable, how- 

 ever, that what is known as var. testacca 

 Emery is really the primitive form of this 

 species. This ant nests in sandy soil and 

 is one of the most abundant insects in 

 the pine barrens of New Jersey and in 

 similar localities in the Eastern States. 

 These are xerophytic regions, as shown by 

 the pines, scrub oaks and many other 

 plants. The sand in which this vegetation 

 grows does not retain water readily and 

 therefore presents conditions not unlike 

 those of the deserts and Great Plains. 

 The dark colored typical imparts is much 

 less abundant and probably represents a 

 secondary adaptation to moist woods and 

 firmer soil. This would explain the exist- 

 ence of repletes in an ant inhabiting rather 

 humid, shady localities. 



Most ants of temperate, mesophytic 

 regions have a mixed diet, consisting of 

 insects, honey-dew and plant secretions. 

 When such species come to live in deserts, 

 or rather arid regions, where the long 

 droughts of summer and the cold of 



winter restrict plant and insect life to a brief season, they usually take 

 on one of the four following adaptations : 



I. They may exaggerate the insectivorous habits which they already 

 possess and become ravenous and highly predatory hunters. They 

 thus manage to secure a sufficient amount of food even under unfavor- 

 able conditions. This adaptation is beautifully shown in the Old World 

 Myrmecocysti (Cataglyphis) , which are represented by the greatest 

 number of species, subspecies and varieties in the deserts of North 

 Africa. The same tendency, however, is apparent in certain races of 

 the American M. inclliger (orbiceps and mcndax). 



Fin. 223. Worker of Cre- 

 mastogaster inflata. a. Lat- 

 eral ; b, dorsal view, X 8. 

 (Original.) 



