ENTOMOLOGICAL CONTRIBUTIONS. Ill 



ing even along the nervures, yet their attachment is very slight, for 

 with the utmost care, I have never succeeded in preparing S. Buffa- 

 loensis ex larva, without an attendant loss of many of its scales. 

 Field collections of Sesia yracilis Gr. & Rob., regarded as " perfect," 

 show none of these scales. 



S. diffinis appears to be eminently a day-flier, for I have never 

 taken it at twilight when others of its congenors and of Thyreus have 

 been abundant. In 1869, I captured it twice on lilac blossoms, but 

 it was usually met with hovering over flowers in open spots, particu- 

 larly those of Lupinus perennis. It was observed at Center, 

 K Y., during the year 1869, on May 25th, 27th, June 1st, 3d, 7th, 

 9th and 15th. The earliest date of its capture which I have 

 recorded, is May 12th. Its usual time of apparition, in this State, 

 would seem to be the last week of May. It has, as appears from the 

 above larval observations, a spring and a summer brood ; the latter, 

 in seasons not unusually forward, may be expected about the last of 

 July, extending into August. 



The female appears to be quite rare. Among a considerable number 

 of captured individuals of the species in my collection, not a single 

 female occurs. 



