TWENTY-FOURTH REPORT ON THE STATE MUSEUM. 



they were dropped head downward ; they readily availed themselves 

 of the assistance, and in a few minutes all had buried themselves out 

 of sight. On the morning of the 13th, twenty-one additional larvae 

 were ready for pupation, and were placed in the same box with the 

 above, in which they soon buried themselves ; none reappeared 

 above the ground, as the Smerinthini in most of my experiments in 

 rearing them heretofore, have shown a tendency to do, probably 

 from the omission of such a preparation of the ground as was made for 

 the present colony. On the 14th and 15th, the remaining nine 

 larvae entered the ground and remained therein, in a small box 

 (6 x 9 x 4), divided into compartments by card partitions, as a pre- 

 ventative against interference in the construction of their cells. 



Perfect insect. On the 30th of July, a male imago was found in 

 the morning to have emerged from pupa, eighteen days after the 

 first larva entered the ground ; on the 31st, five emerged ; August 

 1st, nine (five males and four females) ; on the 2d, two ; on the 3d, 

 eight (six males and two females) ; on the 4th, four ; on the 10th, two, 

 and the last. From thirty-six larvae, thirty-one imagines were obtained. 



Metamorphoses. The length of time required for the several 

 changes above recorded is as follows : 



From deposit of egg to disclosure of larva 7 days. 



disclosure of larva to first molt 6 



first molt to second molt 4 



second molt to third molt 5 



third molt to earthing 8 



earthing to the pupa, probably * 5 



the pupa to the imago 13 



Development of the ovum 7 



Development of the larva 28 



Development of the pupa 13 



Development of the insect . 48 



Double brood. These observations establish the fact not previously 

 recorded of two annual broods for this species, occurring in the months 

 of June and August; of these, captures have been made by me as 

 early as June 9th, and as late as August 16th. It is probable that 

 the larvae from which are produced the first brood of moths, will be 

 found to undergo four moltings. 



Variety. Among the above imagines was a female, having but a 

 single blue pupil on the black ocellated spot of the secondaries. 

 The occurrence of this variety is peculiarly interesting -from the fact, 

 that from specimens diifering from the type of S. geminatas mainly in 



* AB observed in Ceratomia guadricornit, Proc. Ent. Soc. Ph., vol. i. p. 891, Sesia Buffaloensi* and 

 Thyreui Abbotii, pp. 113, 115, of this report. 



