VII PARTHENOGENESIS 255 



since in all cases Siebold found the receptaculum 

 seminis filled with moving spermatozoa, he was able 

 to feel assured that he had really removed the queen 

 in each case. We will merely direct the attention of 

 those interested in histology to the minute description 

 here given of the ovary, which in the main agrees 

 with Leydig's, and of the receptaculum seminis, which 

 in opposition to Leydig, on account of its nerve supply, 

 Siebold holds to be contractile. After waiting some 

 days Siebold had the gratification of finding the first 

 eggs laid in the cells of several of the nests from 

 which he had removed queen, eggs, and larvae, and 

 he felt convinced that they could only have been laid 

 by the small virgin workers who alone tenanted the 

 combs. The whole business of the colonies proceeded 

 just as well as when the queens were there, and the 

 virgins watched and worked with the same assiduity 

 as had done their queen -mother. In some cases 

 Siebold actually saw a worker deposit an egg, and 

 such egg -laying workers, when anatomically tested, 

 showed, firstly, in the presence of corpora lutea (the 

 precise signification of which the investigator had 

 ascertained by his histological studies of the ovary) 

 that eggs had been extruded, and, secondly, in the 

 complete absence of spermatozoa from the recepta- 

 culum seminis, that the insect was a virgin. Out of a 

 hundred nests which he had begun to observe in one 

 season, and out of one hundred and fifty in another, 

 only some twenty or so in each case came through all 

 the long series of accidents from weather, insects, 

 birds, etc., to which they were necessarily exposed, 



