504 The American Naturalist. [j U n. 



the end of which time he gave signs, although somewhat uncertain, o 

 recovering his vision. The animal is well cared for in order that th 

 author may continue his observations for some time to come ; thei 

 later, he will he sacrificed in order that a complete study may be mad 

 of the new formation. (Revue Scientif. 1895, p. 406.) 



ENTOMOLOGY. 1 



Domestic Economy of Wasps.— Much attention has recently 

 been given to the biology of wasps. One of the most interesting ac- 

 counts is that of M. Paul Marchal 2 summarized in the Annals of Mag- 

 azine of Natural History. The investigator studied the earth-burrow- 

 ing wasps (Vespa germaniea, V. vuly'iri.*). The fully-formed nests 

 contain small and large cells, the latter constituting two or more of the 

 lowest combs, while the others make up the six to ten upper combs. 

 The large cells, built only by the workers in August, may, at an early 

 period, receive indifferently either females or males, the former being 

 either queens or very large workers, the latter always in small propor- 

 tion ; after the first of September these cells are entirely set apart for 

 the queens, so that in October no males are to be found in them. 



The small cells, from the time that the laying of eggs for males has 

 begun, contain indifferently up to the end of the season either workers 

 or males. The proportion of males in the combs of small cells decreases 

 from below upwards, with this remarkable exception — that if there be 

 B mixed comb containing both large and small cells, the small cells are 

 influenced by the proximity of the large cells, and contain very few 



The beginning of the period for laying males coincides very nearly 

 with the time of appearance of large cells, early in August. The curve 

 which represents their production rises suddenly in an almost vertical 

 manner to reach its maximum ; it then descends gradually with or 

 without oscillations to the end of the reproduction. The queen takes 

 a prominent part in this great production of males, because the laying 

 workers have already long since disappeared, whilst the young male 

 larvse are still to be found in great numbers in the nest. 



The queen has then (at least after the early days of September) the 

 power to determine with certainty the female sex of the eggs which 



1 Edited by Clarence M. Weed, New Hampshire College, Durham, N. H. 

 Aw, t. cxxi, pp. 731-734. 



