950 



AN INTRODUCTION TO ENTOMOLOGY 



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 EUPARAGIINyE includes the genus Euparagia, 

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



from other Vespidae 

 in that cell M3 of the 

 fore wings is four-sid- 

 ed (Fig. 1 183). Very 

 little is knowii 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 lusitdnicus, 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, othenvise the 

 pupa is naked. 



Ferton ('10) describes the habits of Celomtes 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 



