100 [April, 1905. 



SOME OBSERVATIONS ON HASTULA HYERANA, Mill. 

 BY T. A. CHAPMAN, M.D. 



I took a good deal of interest at Cannes, for some years, in 

 Tortrix unicolorana feeding on Axphodelus albus, in the Esterel. 1 

 found the study of this species very attractive, owing to the peculiar 

 circumstance, that of all the Lepidopterous larvte I knew anything 

 of, that of this species is the only one that certainly confers a favour 

 ou the plant it devours. T unicolorana occurs as a single larva to a 

 plant ; when, very rarely, two occur together, there is little doubt the 

 second one is from an egg laid by a second parent, and the accident is 

 an undesired one. 



When first the larva shows its ravages, when the Asphodel leaves 

 are only a few inches above ground, it looks as if the plant were to 

 be severely punished. As time goes on, however, the larval ravages 

 do not increase much, and the plant grows vigorously. At one stage 

 the outer leaves, or even all the leaves more or less, have a few inches 

 of the tips fastened together by the larval silk, the larva living within 

 this shelter, the leaves a foot or rather less long, instead of falling 

 apart are held together as a tent or sheath over the now just appearing 

 flowering stem. It is just at this period that severe frosts occasionally 

 occur ; in two different seasons I have seen, in the Esterel, ice an 

 inch thick on the rock pools and the little streams, and more than 

 twelve inches at trickles of water over rocks and banks. In both 

 these seasons I also noticed that tlie flowers of the Asphodel were in 

 many cases much injured, but never in those cases where they were 

 protected by the tent of 7'. unicolorana. As ihe Asphodel grows and 

 the leaves become two feet or moi'e long, the spinning of the larva 

 still holds their tips together, and they fall to one side, but look no 

 more deformed than if they had been blown so by the wind. The 

 total damage to the plant is little more than what appeared in earliest 

 spring. A very small price for the plant to pay for insurance against 

 damage to its inflorescence by frost. 



Plate II. 



In many parts of the Esterel I have seen nearly every plant of 

 Asphodel tenanted by a larva of T. unicolorana. 



Tortrix unicolorana is not so abundant at Hyeres as in the Esterel, 

 but it occurs freely enough here on the Asphodelus microcarpus. I 

 was naturally very desirous to make the acquaintance of Hastula 

 hyerana, of which I knew nothing, except that it was rather later than 

 T. unicolorana.^ and replaced it at Hyeres. I was accordingly pleased 



