I 



SMERINTHUS GEMINATUS 



GENUS, smerin'thus (a cord — antennae like cords). 

 SPECIES, GEMiNA'Tus (twin — the cye-spots are double). 



The first time we encountered geminatus was a chance 

 lost. We found a white birch with many rather large, 

 ovoid green eggs laid singly on the under side of the 

 leaves. In a few days the eggs hatched, and as the 

 little caterpillars grew and changed they seemed alike, 

 except that some were bluer-green than others — a 

 difference not unusual in excoecatus, which we had 

 reared and thought we had again found. When the 

 moths emerged the next summer, part proved gemina- 

 tus^ and we were much disgusted that we had not 

 recognized the larvae and kept their record. Even 

 now, however, we should not feel sure of distinguishing 

 geminatus from excoecatus unless we had eggs from a 

 moth we had seen, or which had been seen by some 

 one who knew. The books give geminatus a blue or 

 violet caudal horn and exccecatus a green or bluish one, 

 but we have seen both in one brood of the latter, and 

 cannot consider tliis difference in color a sure test; 

 moreover, some geminatus larvae have pink horns. 



Our nex-t experience was with eggs found on poplar, 

 and we kept a record of the crawlers, whose egg-stage 

 is doubtless about as long as that of excoecatus — about 

 seven days. 



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