Prof. R. L. Edgeworth on Irish Vespidse. 467 



trances observed in an hour ; ov, conversely, the sum of exits and 

 entrances is three times the number of wasps. Accordingly, in 

 a nest of 30,000, the number of exits and entrances would be 

 90,000 per hour, or 1500 per minute ; and such a nest, I be- 

 lieve, has not yet been observed. I should also add that I have 

 seldom seen a nest which contained 2000 wasps. Mr. Smith 

 has seen one with 2590 ; but it is very possible that climate 

 may affect the size of wasps' nests very considerably. The nests 

 of wasps vary in size very much, according to the favourableness 

 of the weather. In dry seasons they are generally larger. The 

 mildness of April and May, not so much as the number of 

 queens seen in the spring, or the quantity of nests the preceding 

 yeai', seems to affect the number of nests for the present year. 

 Wasps are very delicate animals, and peculiarly subject to the 

 influence of the weather ; but the severity and wet of winter 

 itself do not appear to affect their number the following summer. 

 It is impossible, at least from such circumstances, to predict the 

 number or the paucity of wasps. Such, at least, is my expe- 

 rience, confirmed by carefully comparing the various notices in 

 the ' Zoologist,' which form valuable statistics on this point. 



The Vespa Germanica seems to be almost a variety of the V. 

 vulgaris ; at any rate, the habits of the two are so similar that 

 one descriptioD will answer for both. The Vespa vulgaris is the 

 common wasp of Ireland; but in the county Down Mr. Haliday 

 assures me that V. rufa is more common. I give no description 

 of this or any other wasp, as Mr. Smith has already completely 

 exhausted the subject ; but it is worth while remarking that the 

 colour and size of this insect seem to depend very much upon 

 the locality in which its nest is situated. I have observed that 

 nests which face the sun generally produce .small, bright yellow, 

 very active wasps, whereas the wasps from nests in dark and 

 shady places appear larger, darker, and lazier. The same phe- 

 nomenon is to be seen among ants — some being lighter and, 

 some darker than others, without any other very apparent cause 

 than that suggested by the situation of their nest. It has also 

 been remarked that each individual wasp as it grows older alters 

 considerably in size and colour. 



Locality selected for Building. — The situation in which each 

 wasp builds is generally very characteristic of the species, and 

 therefore it is a matter of some importance to endeavour to as-, 

 certain the usual locality selected by each different wasp. The* 

 nests of V. vulgaris are generally formed in dry banks, in the 

 roots of decayed trees, and occasionally in the thatch of cottages 

 or other similar places, but may occur almost anywhere. Mr, 

 Smith says he has seen one in a pump. In the ' Transaction^ 

 of the Ashmolean Society' (xx. 3), a nest was found in a loaf of 



