224 



PSYCHE. 



[July, igoi 



larvae of Microdon niiitabilis were com- 

 pletely ignored by the ants in a mixed 

 colony of Formica saiiguinea-fusca. 

 Bnt h'e observed that the fly, which is 

 covered with delicate yellow pile, was 

 assiduously licked by F. saiigiilnca 

 although it soon died. Except for this 

 last observation, vvliich relates only to 

 its imaginal stage, Microdon may be 

 regarded as belonging to Wasmann's 

 category of synoeketic myrmecophiles, 

 or indifferently tolerated guests, a great 

 company which also comprises the tiny 

 crickets of the genus Myrmecophila. * 

 The imagines of a number of species 

 of Microdon have been described from 



North America but they all appear to 

 be rare insects. They fly reluctantly 

 and are fond of lurking about the roots 

 of grasses and other plants in situations 

 where they readily elude the observation 

 of the most careful collector. I am un- 

 able to conjecture to which of the de- 

 scribed Mexican species the larva ob- 

 served in the Pseudomyrma nests be- 

 longs. The accompanying photograph 

 will enable any future observer to iden- 

 tify it without much difficulty, even if 

 it should be found, as I have no doubt 

 it will be, in the nests of other species 

 of ants in Mexico and Central America. 



NOTE.S ON THE MATING OF ATTACUS CECKOPIA AND OTHERS. 



BY CAROLINE G. SOULE, EROOKLINE, MASS. 



In most of the large collections of 

 cecropia cocoons which I have examined 

 the female pupae have outnumbered the 

 male by about five to one, twice by three 

 to one. For this reason I have inferred 

 that the males were polygamous, and 

 this spring I have tested them, as the 

 moths emerged very early. 



Close observation has convinced me 

 that the female cecropia requires sixteen 

 hours out of the cocoon before she is 

 ready to mate. In no instance did a 

 female protrude the whole ovipositor 



*See Wlieeler, The Habits of Myrmecophila nebras- 

 censis Eruner. Psyche. Oct., 1900. pp. 1 11-115 ; and Was- 

 mann, Zur Lebensweise der Ameisengrilleii (Myrmeco- 

 phila). Natur u. Offenbarung. 47. Bd. 1901pp. 129-152). 



sooner, and in no instance did the male 

 in the cage with her attempt mating or 

 seem in the least attracted or excited 

 before the protrusion of the whole ovi- 

 positor. Partial protrusion occurs ear- 

 lier. 



I feel convinced that there is a differ- 

 ent odor diffused when the whole ovi- 

 positor is protruded, in the case of all 

 the large Saturniids, and often I think I 

 can detect it in spite of the previous 

 powerful odor of both male and female. 



With one exception no female flew or 

 moved about the cage after her wings 

 were expanded until mating had taken 

 place, nor did any female show the least 

 sign of noticing the male or of preference 



