284 fiNtOMOLOGlCAL NEWS. [Nov., '05 



Some of my larvae which I placed together with lupine 

 stumps in a large glass aquarium half filled with sandy soil, 

 buried themselves in the latter, others were contented with 

 holes in lupine into which I introduced them. These latter 

 immediately closed the entrance to the burrows with particles 

 of wood fastened together with silk, those which had descended 

 into the soil pupated therein mostly in January and February. 

 The larvae in the lupine appeared to hibernate as well as those 

 in the earth, as they ate little or nothing and did not pupate 

 for some time. 



The cocoons formed below the surface of the soil do not 

 differ essentially from those spun in the lupine. Both vary in 



Hepialus sequoiolus. Fig. I, mature lan'a. 



length, some being hardly two inches long, while others are as 

 much as six inches or even more in length. 



Those cocoons spun in the soil extend vertically in the same 

 to within a fraction of an inch from its surface. Grains of 

 earth loosely attached to the cocoon form a weak outer cover- 

 ing. The cocoon itself is quite thin but of strong texture, 

 dirty white or brown, cylindrical in form, usually more pointed 

 below and weakly closed at its summit. In making this 

 cocoon which requires several days, the larva appears to work 

 by night, rounding off the cocoon, smoothing its sides and 

 probably enlarging it by strking the wall of the cocoon with 

 its strongly chitinized head which together with the forepart of 

 its body it vibrates rapidly from side to side. This procedure 

 continues for two or three seconds at a time and when the 

 cocoon is spun against a hard surface, this vibration produces 

 a sharp rattling noise audible from quite a distance. When 

 the vibration ceases the larva resumes its spinning until more 

 thumping is necessary. The cocoon being finished the larva 

 retires to its basal part where, in the course of a few days or in 

 some cases in a few weeks, the pupa is formed. Those larvae 



