APATHUS. 305 



closely, or nearly so, resembling its sitos, if not al- 

 ways in colour, certainly in habit. Having no labours 

 to undergo they consist of merely males and females, 

 but the latter, although very like the large female Bombi, 

 are much less pubescent than these, for they have a broad 

 disk, upon the upper surface of the abdomen, always 

 smooth and shining. Both sexes appear to have free 

 in- and egress to the nests of those Bombi which they 

 infest, without any let or hindrance on the part of the 

 latter, with whom they seem to dwell in perfect amity. 

 In the times of their appearance they closely resemble 

 the Halicti and the neighbouring Bombi. Thus the 

 females, after impregnation in the autumn, having hi- 

 bernated during the winter in selected receptacles, come 

 out with the first gleams of -spring conjunctively with the 

 large maternal Bombi, in whose nests they have taken 

 their long repose in perfect torpidity ; and as soon as 

 these begin to accumulate the masses of conglomerated 

 honey and pollen whereon to deposit their eggs, the 

 parasite takes advantage of it, lays her eggs too, and 

 thus secures food for her offspring. There being two 

 broods of them in the year, many are gradually deve- 

 loped with the advance of summer, but the great hatch- 

 ing takes place in the autumn, when the thistles are in 

 blossom. Then both males and females come forth in 

 abundance, the latter are made fertile, and their partners 

 enjoy the brief interval of the still blossoming flowers 

 until the usual period is put to their existence by natural 

 decay, the first frosts, or the rapacity of insectivorous 

 birds. Connected with this last circumstance I have a 

 personal experience to record, and which its repetition 

 would indicate as being one of .Nature's prompting acts. 

 A lofty sandy level, very near the high-road which leads 



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