NOTES 



ON THE THELE-PERCEPTION OF SEX IN 

 SILKWORM MOTHS 



PROFESSOR OSV. POLIMANTI 



The Physiological Institute of the University of Perugia 



While carrying on a series of researches on the caterpillar of 

 Bombyx mori L., 1 my attention was attracted by a phenomenon 

 presented by the male moth just after emerging from the cocoon. 

 The moth began to move its wings very rapidly while clinging 

 with its feet to some one of the still unopened cocoons, and it 

 remained thus even after the moth from that cocoon had emerged. 

 It occurred to me that this might be due to the fact that the 

 unopened cocoon held a female, to which the male was guided 

 by some peculiar scent. After postponing for several years any 

 attempt to prove the truth of this supposition, I have at last 

 made some systematic observations which are here recorded. 



It has long been noticed by naturalists that the male moths 

 of the Bombicidae, immediately on emerging from the cocoon, 

 seek out the female, guided, it is supposed, by the sense of 

 smell. The wings of the female are not well developed, and 

 they seldom fly far; the males, on the other hand, may make 

 real migrations in search of the female. 



It is also well known that certain moths emanate peculiar 

 odors. The seat of the odor was shown by Fritz Mliller 2 to be 

 small blades provided with a gland at the base, situated in the 

 superior part of the anterior wings near the junction with the 

 thorax. To these he gave the name "Andraconia." He de- 

 scribed the odors of a large number of moths and butterflies, 

 some of which were pleasant and others disagreeable. Miiller 



1 Polimanti, O. Contribute alia fisiologia del baco da seta ( Bombex mori) Scan- 

 sano. Tessitori. 1906. Contributions a la physiologie de la larve du ver a soie 

 {Bombyx mori). Archives italiennes de biologic T. 47. 1907. P. 341-372. 



2 Miiller, Fritz. 1. Wo hat der Moschusduft der Schwarmer seinen Sitz ? 

 Kosmos. 1878. 2 v. 3. p. 84. 2. Duftbiischel von Sphingiden. Transactions 

 Entomological Society, London. 1878. P. 2. 



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