1918.1 121 



variable, even in healthy examples, that an examination of this character 

 in stylopized ones is not of much value. The surface of the 2nd 

 abdominal segment of parasitized individuals is generally duller than 

 in normal ones, this being apparently chiefly due to a change in the 

 minute surface sculpture between the punctures. The male bee, 

 attacked only by $ Sti/lops, is, • in the material examined, generally 

 less a:ffected than those yielding 6 parasites, and sometimes hardly 

 differs from a healthy individual. 



Female bees with male Stylops may have the abdominal pubescence 

 greatly shortened or diminished on the second segment and excessively 

 short on the following ones. In those bearing the female parasite the 

 pubescence of the apical impressions of the segments often forms wider 

 or more distinct pale bands there than in normal specimens, though 

 more or less evident bands may generally be seen in the latter in 

 some aspects. 



The tibial scopa shows more or less degeneration in all the speci- 

 mens that I have examined, thousrh in some this deoreneration is slisrht. 

 In one certainly stylopized, though the Stylops itself is not visible 

 (either having died as a larva or not developed sufficiently to push out 

 its head through the intersegmental membrane), enough pollen remains 

 in the scopa and in the femoral basket to show that this is no accidental 

 collection. Another very old one with discoloured and tattered "wings, 

 the abdomen almost entirely denuded, and the head and thorax largely so, 

 bears a single discoloured $ Stylops, which has probably produced its 

 triungulins. It was caught during the first half of July 1911, so that 

 its life must have been a long one. I have minutely examined about 

 forty stylopized examples in making these notes and have seen very 

 many others in past years. Both the external and internal changes 

 caused by Stylops in this species have been detailed by Geoffrey Smith 

 and Hamm in their paper already referred to. 



2. A. fihialis {atriceps), — The effect of stylopization is in general 

 like that shown by A. nigroaenea, the (5 d of these two species being 

 very^ similar superficially, but structurally remotely allied. The 6 in 

 healthy examples varies in the colour of the facial clothing, but in the 

 $ normally the face is pale-haired, with whitish or whitish-fuscous hair 

 below the line of the antennae. The latter sex has yellow or red 

 hind tibiae. 



In the worst affected males (<?. y. one n'om which .several J Stylops 

 liave issued) the alxlomen is shining and appears nearly glabrous to the 



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