Bramble-bees and Others 



male has about a week's start. Consequently, 

 in a populous gallery, there is always a certain 

 number of males, who are hatched seven or 

 eight days before the females and who are dis- 

 tributed here and there over the series. This 

 would be enough to make any regular hatch- 

 ing-sequence impossible in either direction. 



These surmises accord with the facts : the 

 chronological sequence of the cells tells us 

 nothing about the chronological sequence of 

 the hatchings, which take place without any 

 definite order. There is, therefore, no sur- 

 render of rights of primogeniture, as Leon 

 Dufour thought: each insect, regardless of 

 the others, bursts its cocoon when Its time 

 comes; and this time Is determined by causes 

 which escape our notice and which, no doubt, 

 depend upon the potentialities of the egg it- 

 self. It is the case with the other bramble- 

 dwellers which I have subjected to the same 

 test {Osmia detrita, Antliidium scapiilare, So- 

 leniiis vagus, etc.) ; and it must also be the 

 case with Odyncriis rubicol: so the most stri- 

 king analogies inform us. Therefore the sin- 

 gular exception which made such an impres- 

 sion on Dufour's mind is a sheer logical 

 delusion. 



19 



