HYMENOPTERA 



967 



subfamilies, however, is not regarded as a natural division of the 

 family Vespidas, as each of the two groups is believed to be poly- 

 phyletic, and too, F. X. Williams ('19) has shown that in the genus 

 Stenogaster, found in the Oriental and Australian regions, some species 

 are solitary and others are social; but this grouping is useful in a 

 discussion of the habits of these insects 



THE SOLITARY DIPLOPTERA 



Fig. 1 1 83 .—Wings of Euparagia scutellaris. 

 Bradley.) 



(After 



The subfamily EUPARAGIIN^ includes the ^quus Euparagia, 

 two species of which are found in the Southwest. These wasps differ 



from other Vespidas 

 in that cell M3 of the 

 fore wings is four-sid- 

 ed (Fig. 1 183). Very 

 little is known regard- 

 ing the habits of these 

 insects. For figures 

 and descriptions of 

 the species see Brad- 

 ley ('22). 



The subfamily 

 MASARIN^isavery 

 widely distributed 

 group but it is repre- 

 sented in our fauna 

 only by the genus 

 Pseudomdsaris, of 

 which thirteen species have been described; these are found in the 

 Far West and Southwest. In these wasps there are only two sub- 

 marginal cells in the fore wings and the antennae are clavate. The 

 North American species were monographed by Bradley ('22). 



There are but few accounts of the nest-building habits of masarid 

 wasps. Giraud ('71) describes the habits of Ceramius lusitdniciis, a 

 species found in France. This is a mining wasp, which digs a burrow 

 in the ground, leading to a cell, in which the larva lives. The larva 

 is fed by the mother, who brings to it from time to time a supply of 

 a paste, described as being somewhat like dried honey. When the 

 larva is full-grown it lines its cell with a layer of silk, otherwise the 

 pupa is naked. 



Ferton ('10) describes the habits of Celonltes abbrevidtus, another 

 species found in France. This is a mason wasp, which makes earthen 

 cells attached to the sides of rocks or to stems of plants. A figure of 

 one of these nests is given by Sharp ('99) page 89. In this figure 

 the cells are represented as opening downward. This species also 

 provisions its nest with a paste made of pollen and honey ; and the 

 full-grown larva lines its cell with silk. 



The most remarkable feature in the habits of these two species 

 is that they provision their nests with a paste made of pollen and 



