20 Bulletin of the Brooklyn Entomological Society Vol. XI 

 NOTE ON PSENOCERUS SUPERNOTATUS. 



By R. p. Dow, Brooklyn, N. Y. 



In January I inspected a number of twigs of sumac, two species, 

 Rhus copalina and R. glabra, hoping to find evidences of Nemo- 

 soma cylindricum. The live twigs contained nothing, the dead 

 ones were thickly populated with very small Scolytid larvae and 

 some species of Cerambycid, the almost full grown larvae boring 

 the pith chamber lengthwise. 



A bundle of twigs put in a cloth covered jar yielded imagos 

 in April. The longhorn proved to be Psenocerus supernotatiis. 

 This seems to be a new food plant record. The New Jersey list 

 gives currant, but others are known. 



The first arrivals were two males, one about twice as big as 

 the other. On the first day both were observed to find an attrac- 

 tion in a particular spot on one of the twigs. They met and 

 fought. The smaller had his left antenna bitten off above the 

 third joint. Two days later I inspected the jar at daybreak. 

 The " woman in the case " had arrived, making her entrance on 

 the very spot where the fight had occurred and had already gone 

 to housekeeping, but with the cripple as her partner. The victor 

 was not seen to come near them. It is evident that some sense 

 organ revealed the female to the males not less than 36 hours 

 before her emergence from the unbroken wood. 



Two weeks later a number of Liodes alpha emerged from the 

 twigs. This was the species to be expected from this food plant. 



