100 PARTHENOGENESIS 



the idea, whether the property possessed by certain female silk- 

 worm moths, of laying eggs capable of development without 

 fecundation, might not be of use in furnishing aid to his theory 

 of the reproduction of the Bees, by means of exact trials and 

 experiments. In consequence of this, Dzierzon recommended 

 such experiments to the silk-worm breeders*. 



Experiments were hereupon made in this direction in several 

 quarters with silk- worms, but up to this time the reports furnished 

 of them are still imperfect f. A notice contained in these 

 Reports from Dr. Kipp, who had obtained a quantity of eggs, 

 and from all these caterpillars, from a Poplar Hawk-moth (Sphinx 

 Populi) which had been excluded and kept shut up in a box, 

 speaks against Dzierzon's theory, as both male and female moths 

 were reared from these caterpillars J. I myself took the greatest 

 trouble with the rearing of those young caterpillars which I had 

 obtained from the unfecundated silk-worm eggs given to me by 

 Herr Schmid, and of fifteen caterpillars which grew large, I 

 brought twelve individuals to spin up. The different forms of 

 the cocoons at once allowed me to judge that different sexes 

 would be excluded from them, and subsequently seven male and 

 five female moths actually crept out of these twelve cocoons. To 

 convince myself whether these moths produced by Partheno- 

 genesis were really sexually mature and capable of propagation, 

 I did not prevent them from copulating, which they did imme- 

 diately on making their escape. After the performance of copu- 

 lation the females deposited a number of eggs, which showed 

 themselves to possess vitality, and in the following year furnished 

 the same number of caterpillars. Schmid, who had supplied me 

 from his store of unfecundated, vitalizable silk-worm eggs, made 

 similar experiments at the same time with the rest of the eggs 

 which he had retained, and obtained the same result as myself. 

 That Schmid performed his experiments with great care and with 

 the necessary caution, appears from the report which he sent 

 me on the subject, from which I extract the following as worthy 

 of notice. In the year 1853, Schmid captured twenty-four silk- 



* See the Bienenzeitung , 1853, p. 103. 



t Bienenzeitung, 1853, pp. 144 & 175, and 1855, p. 26. 



J Bienenzeitung, 1853, p. 175. 2. 



