542 PROCEEDINGS OF THE ACADEMY OF [Oct., 



the ants, and its sprouting spores may be seen on their surfaces 

 under a magnification of about five hundred diameters. If the 

 spores are left undisturbed they cover the young with a delicate 

 dense white coat that becomes sage-green with the ripening of the 

 new spores. It appears j^robable that the ants find nuti'iment in 

 the new mycelium of the mould, from which they relieve the young 

 by licking them frequently and thorouglily. If the surfaces of 

 the ant-children be a kitchen-garden spontaneously supplying the 

 nurses with aliment, then these ants enjoy an economic indepen- 

 dence surpassed only liy that of an ideal creature that could lay 

 eggs sufficient for its own nourishment. 



This delicate mould does not grow upon the bodies of dead 

 ants, but is there replaced by Rhyzopus nigricans, with long and 

 spreading hyphse, and in this may lie the cause for the carrying off 

 and casting away of all ants that die or are kiUed in the nest. 



So long as the eighth and ninth segments of the antennce are unin- 

 jured, the ant may continue to lift and care for the eggs, larvce or 

 pupce, but after the removal of these segments she loses all interest in 

 the young and performs no further ivork in the nursery. I proved 

 this to be true in several CDlonies. In ray colony B, which had 

 been queenless during many months, the workers had been singu- 

 larly devoted to the larvse and pupse from their own eggs,^" and from 

 among these ants I selected several that never failed to lift a larva 

 when the cover of their Petri cell was taken away. Some of these 

 assiduous nurses took all usual precaution for the safety of their 

 young so long as the eighth segments of the antennre were unin- 

 jured, but none lacking the eighth segment ever gave heed to 

 nursery duties of any sort. From none of the other ants could I 

 secure any attention to the young after the excision of the ninth 

 segment. 



Marked ants of two hostile colonies, when clipped across the 

 tenth segment, associated freely and amiably with one another 

 during several days in the care of pupas belonging to one of the 

 two colonies. A whole queen resident in the small nest appeared 

 unable to tolerate the alien odor among the nurses, and often with- 

 drew from the ever-alluring pupio pile where they congregated. 

 When the callows appeared, the queen aggressively took her place 



'- One of these worker's-egg-larv£e, separately reared, was oue hundred 

 and forty days in the larval stage. 



