SAC-BEARING LEPIDOPTERA. 31 



opening in the hinder whorls of the sac, although the animal 

 with its empty, shrivelled body could easily force its way out 

 through the uppermost narrow whorl, and through the narrow 

 aperture at the apex of the sac. But there is probably another 

 circumstance which prompts the caterpillar instinctively, \vhilst 

 finishing and enlarging its sac, to introduce a lateral opening 

 below the uppermost narrow whorl ; I mean the eventual per- 

 mission of the act of copulation, which in this case, from the 

 peculiar form of the sac, could only be effected through a low 

 lateral aperture of this kind. 



This Sac-bearer was first mentioned by Reaumur*, but has 

 since remained entirely unnoticed by entomologists. It is only 

 very recently that greater attention has been given to these 

 Heliciform caterpillar-sacs. My attention was first called to 

 this Sac-bearer in Freiburg in the latter part of the summer of 

 1849 by Von Heyden, to whom entomology is indebted for so 

 many interesting discoveries. It was discovered by Von Heyden 

 spun down on rocks on the Schlossberg near Freiburg, and sub- 

 sequently the same animal was found on the Isteiner Klotz be- 

 tween Freiburg and Basle f- This Sac-bearer was forwarded to 

 me by Zeller from the neighbourhood of Glogau, and I received 

 several living specimens, collected a couple of miles from Vienna, 

 near Modling, through the kindness of Kollar, in whose com- 

 pany I afterwards (in the year 1850) collected many specimens 

 in the same locality. Dr. von Frantzius also brought me some 

 specimens of this Sac-bearer from Meran. By Herrich-Schaffer's 

 intervention, I obtained many of the same sacs from the district 

 of Tegernheim near Ratisbon, and this Sac-bearer was also ob- 

 served by Mann and Zeller in Sicily J. Besides the habitat 

 given by Reaumur, Besanyon and Dijon in France have recently 

 been indicated by Bruand as localities for this Sac-bearer . In 



* See Memoires pour servir a I'Histoire des Insectes, torn. iii. part i. edit. 

 12mo, p. 249. pi. 15. fig. 20-22, figures of the sac of Psyche Helix (see the 

 copies of these in my plate, figs. 10-12). 



t See Reutti's Uebersicht der Lepidopteren-Fauna des GrossJierzogtJiums 

 Baden, in the Beitr'dge zur rkeinischen Naturgeschichte, Heft 3. 1853, p. 49. 



J See my Bemerkungen iiber Psychiden, in the Jahresbericht der schlesischen 

 Gesellschaft flir vaterlandische Cultur iiber 1850, p. 87 (transl. Ent. Trans. 

 new ser. vol. i.). 



See his Essai monographique sur la Tribu des Psychides, in the Memoires 



