134 H. von Ihering on the 



exist in an almost inactive condition with a diminished 

 number of individuals : it is true that this is not the case in 

 Rio Grande do Sul, though it certainly occurs in Sao Paulo. 

 In Rio Grande do Sul it was a very remarkable sight to watch 

 PoUstes (females and workers) at the commencement of 

 winter seeking out human habitations, in order to search for 

 suitable hiding-places in which to hibernate. Even thus many 

 perish, but in spring I have repeatedly seen on freshly-begun 

 nests a female carrying on building-operations already in 

 company with workers. Whether in such cases remnants of 

 a colony have come together to build a new home, or whether 

 the hibernated female has accepted the assistance of chosen 

 hibernated workers, I am unable to say. 



In the case of PoJyhia and its allies the influence of winter 

 is much less noticeable than in Polistes. Polyhia scutellaris^ 

 White, still hibernates even in Rio Grande do Sul. The 

 very solid prickly envelope of the large nest doubtless aflbrds 

 a good protection against the weather. Moreover this very 

 species collects honey freely and in relatively large quantities. 

 It is amassed in pretty irregular fashion in the lower cells, 

 especially at the edge of the combs, but it nevertheless in- 

 duces boys, and also adults with a penchant for sweets, to 

 destroy the nest. I have seen many nests inhabited for a 

 long period. Here in S. Paulo, too, I have made the same 

 observation upon the paulista variety of this wasp, which 

 will be referred to later on. It is consequently not a matter 

 for surprise when one notices these wasps again in the open 

 during exceptionally fine weather in the middle of winter. 



Another new observation upon Polyhia is the fact that it 

 swarms. Whether a fertilized female PoJyhia is ever capable 

 of commencing a nest alone, as is, indeed, still probable, is a 

 point which iuture study must decide : at any rate, it is not 

 the rule for it to do so. I have very often observed the com- 

 mencement of new nests of Polyhia ; the task was .ilways 

 undertaken by a swarm. A closely packed cluster of Polyhia 

 scutellaris, of the size of a large orange or larger, settles on 

 some spot or other, often by no means a suitable one, without, 

 however, at once deciding to begin to build. 



Not infrequently is the spot changed several times before 

 work commences. Then, however, it proceeds astonishingly 

 fast, so that in from two to three weeks a nest is built con- 

 taining from four to five combs. At the same time, however, 

 the whole of tiie attention is in the first place devoted exclu- 

 sively to nest-building, so that one finds charming new nests 

 with from three to four combs in which there is not yet a 

 single cell that has received even an egg. In the case of 



