201 



the form of a white mycélium likc thai cultivated by some olher 

 species of Cyphomyrmex {C. Wheeleri Forel, for example) but 

 consisiing of cluslers of small orange yellow, sphcrical or pyriform 

 nodules about 5 mill. in diameter. The exhausted masses of 

 Caterpillar- excréta are piled on the refuse heap in a distant corner 

 of the nest. The eggs of C. rimosus are very broad and short, 

 almost spherical. 



9. Cryptocerus aztecus Forel. 



Cuernavaca, Dec. 27. Common, nesting in the epiphytic Tillandsias 

 in a small acacia grove south west of the town. Soldiers and workers, 

 larvae and pupae were stored like sardines between the leaves of the 

 Tillandsias. No maies or females were seen. This species was often 

 found in parabiosis wiih Cremasfog aster brevispinosa Mayr (See 

 Wheeler : The Double and Mixed Nests of American Ants. American 

 Naturalist, 1901). 



10. Cryptocerus Wheeleri Forel. 



In the same situations as the preceeding but rarer. A single 

 immature maie was taken in one of the nests which was in the same 

 Tillandsia bud as a nest of Cremastog aster. 



11. Tetramorium (Xiphomyrmex) ^TVheeleri Forel. 

 Pacheco in Zacatecas, Dec. 21. A small colony found under a stone 



in the cactus-covered désert. This, or a very closely allied species, 

 occurs also at Austin, Texas. 



12. Wasmannia auropunctata Roger, var. rugosa Forel. 



Cuernavaca, Dec. 25. A single large nest under a stone in a hilly 

 pasture south of the town. The nest contained huudre is of workers 

 wiLh a single queen. In its movements and the style of its nest, which 

 is an irregular chamber dug about th-^ roots of the grasses, this ant 

 reminds one of Cyphomyrmex. The nest contained a small mass of 

 ihe same peculiar fungus as in the nests of Cyphomyrmex rimosus 

 above described, but it Was impossible to détermine the nature of the 

 substance on which it was growing. 



13. Leptothorax petiolatus Forel. 



Cuernavaca, Dec. 25. A single nest cousisting of a deàlated queen 

 and about 25 workers in a Tillandsia in parabiosis with Cryptocerus 

 and Cremastog aster. 



14. Stenamma (Ischnomyrmex) Cockerelli André. 

 Pacheco in Zacatecas, Dec. 21. Common in the cactus-covered 



désert under moderately large stones. It makes large, irregular bur- 

 rows in the coarse pebbly scil. 



