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Amongst the early bees is found one, whose habits are veiled in 
mystery, it is a bee without the necessary hirsuties for conveying 
pollen; these are invariably absent in the parasitic bees, but it does 
not necessarily follow that all bees without these appendages are 
parasitic, for example: the genus Prosopis or Hylceus, is entirely 
without them, but are, nevertheless, constructive bees; the parasitic 
bee lays its eggs on the honey and pollen collected by another bee, 
when it finds one suited for its purpose ; many of these parasites 
are constant in their attacks on certain species of constructive bees, 
others (of which perhaps the best example is Nornada rujicornis), 
attack several species varying greatly in size, and consequently in 
the quantity of honey and pollen they collect for the future young; 
the Nornada vary in size according to the species they attack, the 
size being influenced by the quantity of food ; the above mentioned 
insect varies from three to six lines ; as a rule there is not a great 
variation in tho size of the constructive bees, but amongst the 
Sphecodes there is just the same variation in size as there is in 
the Nornada’ ; these insects are generally found running or flying 
about the dry banks infested by tho Halicti, which in the different 
species, vary as much in size as the specimens do in the species of 
Sphecodes. 
And it is not Halictus only that Sphecodes attacks, (that is 
supposing it to be parasitic) for in May last I found a large colony 
of And rena albicrus, which had made their holes in the hard 
ground by the side of a road, and flying about the burrows, were 
several large specimens of Sphecodes rufescens, busily hunting 
about the burrows, the entrances to which were not exposed, but 
each was covered by a little heap of dry dust, which is pushed out 
by the insect when forming the hole; presently I saw a female 
Andrena turn its head downwards into one of the little 
heaps of dust, as they did when they wanted to enter the burrow ; 
at the same instant up flew a Sphecodes, and by tugging at its 
legs and wings, tried to pull the A ndrena out, which at last, I 
suppose annoyed by the persistence of the Sphecodes, turned out 
and flew away, when the latter quartered the ground in all direc- 
tions, as if searching for some thing it had lost, and not being sue- 
