LONGEVITY OF A VELVET ANT. 



ADELE M. FIELDE. 



Finding no printed record concerning length of life in the 

 Mutilidae, I think there may be value in an observation recently 

 made by me upon a single female of Spheropthalmia occidentals. 



She was captured in Arizona early in June, 1905, by Professor 

 Edward S. Morse, of Salem, Mass. ; reached my hands on the 

 first day of the ensuing August ; and lived under my observation 

 until the twelfth of August, 1906. She was kept by me in a 

 small glass ant-nest of the Fielde pattern, in which I fixed three 

 glass vials whose interior diameter was scarcely greater than that 

 of her own abdomen. Into one of these vials she often crept ; 

 and she hibernated there during the winter of 1905-6, at a tem- 

 perature between 65 and 75 F. Whenever the temperature 

 rose as high as 80 F. she awoke, walked about and perhaps 

 ate from the particle of honeyed sponge-cake that always awaited 

 her in the adjoining compartment of the nest, where there was 

 also a bit of sponge that was kept saturated with clean water. 

 In summer she often sought the more humid part of the nest. 



She preferred darkness to light ; but, like the formicid ants, 

 she avoided only the ultra-violet rays. When sheltered by an 

 orange pane which excluded the ultra-violet rays, she was mani- 

 festly unaware that she was not in complete darkness. Like the 

 formicid ants she appeared to be blind to other than the actinic 

 rays. 



When first received by me, she once stung me sharply, but 

 thereafter she became acquainted with my hand, seemed to 

 greatly enjoy walking about upon it, and never left it willingly 

 except to enter her nest. 



I never heard her stridulate when in the nest ; but whenever 

 I enclosed her in the warm darkness of my fist, she sounded her 

 charming, harmonious notes, representing but two keys. Prob- 

 ably each key was determined by one of the two overlapping 

 sclerites on the top of the abdomen. Great variation in the 



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