Bramble-bees and Others 



Is there nothing beyond a laying in two series? 

 Are the Osmiae, the Chalicodomae and the rest 

 of them fatally bound by this distribution of 

 the sexes into two distinct groups, the male 

 group following upon the female group, with- 

 out any mixing of the two? Is the mother 

 absolutely powerless to make a change in this 

 arrangement, should circumstances require it? 



The Three-pronged Osmia already shows 

 us that the problem is far from being solved. 

 In the same bramble-stump, the two sexes 

 occur very irregularly, as though at random. 

 Why this mixture in the series of cocoons of 

 a Bee closely related to the Horned Osmia 

 and the Three-horned Osmia, who stack theirs 

 methodically by separate sexes in the hollow 

 of a reed? What the Bee of the brambles 

 does cannot her kinswomen of the reeds do 

 too? Nothing, so far as I know, can ex- 

 plain this fundamental difference in a physi- 

 ological act of primary importance. The three 

 Bees belong to the same genus; they resemble 

 one another in general outline, internal struc- 

 ture and habits; and, with this close similarity, 

 we suddenly find a strange dissimilarity. 



There is just one thing that might possibly 

 arouse a suspicion of the cause of this irregu- 



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