ARRANGEMENT OF MALE AND FEMALE CELLS. 261 



inner narrower portion with a diameter of five to five 

 and a half millimetres, which is too small for a female, 

 but just large enough for a male. This arrangement 

 placed the Osmias in a difficulty. Thoy could not 

 follow their natural instinct and construct at the end 

 of the tube cells large enough for females. 



What happened ? Some of the Osmias shut off the 

 narrow ends, and used only the outer wider portion. 

 Others, reluctant, as it were, to throw away a chance, 

 built also in the narrow part of the tube, and under 

 these circumstances, contrary to the otherwise invari- 

 able rule, the inner and fiist constructed cells contained 

 males. 



M. Fabre concludes then, and it seems to me has 

 given very strong reasons for thinking so, that these 

 privileged insects not only know the sex of the insect 

 which will emerge from the egg they are about to lay, 

 but that at their own will they can actually control it ! 

 Certainly a most curious and interesting result ! 



He concludes his charming work as follows : — " Mes 

 chers insectes, dont I'etude m'a soutenu et continue a 

 me soutenir au milieu de mes plus rudes epreuves, 11 

 faut ici, pour aujourd'hui, se dire adieu. Autour de 

 moi les rangs s'eclaircissent et les longs espoirs ont fui. 

 Pourrai-je encore parler de vous ? " and every lover of 

 nature will, I am sure, echo the wish. 



