44 PROTECTION OF PLANTS, 1918-19 



and dark brownish in colour. Not having been successful in rearing larvae in 

 cages it is difficult for me to give details of the duration of the different stages of 

 the insect. 



The following, however, are several dates for 1916 and 1917 — April 18 

 emergence from the ground ; April 22nd exrcavation of the gallery; April 2nd and 

 29, mating, May 22nd egg found in cell. Small larva in another cell. August 30th 

 and November 29th adults, pupae and well developed larvae found in different 

 nests. This latter date, when the soil is already frozen, shows us that the Colletes 

 pass the winter in different stages. One cannot do justice in words to the dainty 

 appearance which these bees present, when at the end of the autumn one tears 

 asunder the delicate membranous shroud which shelter them. 



There they are, immaculate and fresh looking, in an attitude of profound 

 meditation, the tarsi folded over on the chest, the wings perfectly developed, their 

 little silky fleece unruffled. 



Surely it would seem just that bees, so gentle and hard working as these, 

 should have no enemies? Alas as in our human society, here also exploiters are 

 to be found. Averse to toil they are, and they only seek how they may make 

 profit out of the labours of honest workmen. 



Flying unceasingly in the neighbourhood of the colony, they watch for the 

 favourable moment, when the mother departs to collect provisions, to penetrate 

 the cell, then to effect their egg laying and depart hastily, to repeat the same deed 

 elsewhere. 



Such is the case with Sphecodes dichroa. More than once I have seen her 

 slipping into a tunnel in the absence of its owner ; at times however, her plans go 

 awry, and she ventures into an occupied domain. The intruder is quickly sent 

 about her business; hustled out, knocked over and roughly handled, she is thrown 

 out of the gallery, and departs hastily, content to have got off so easily. Others 

 Bomhylius major and 5. pygmaetis act in a different fashion; as quick as lightning 

 they flash over the site of the nest; now here, now there they fly, so quickly that 

 the eye can hardly follow them. All at once they come to a standstill, like a 

 fixed point in the air they hover motionless over the site of the orifice. Then in 

 one mass they drop to the ground, hardly stopping for an instant at the entrance 

 to the gallery. The moment of action, short as it is, suffices for the disposition 

 of a minute egg, which in all probability the Colletes herself in her comings and 

 goings will unconsciously suffer to remain. The study of these Dipterous 

 parasites forms the basis of a very interesting subject, which if fortune favours me 

 I shall pursue. 



We have now thoroughly investigated the life history of Colletes inaequalis, 

 her birth, diversions, labours and mishaps. But this life is a short one; those 



