A SYNOPSIS OF THE APHIDIDAE 43 



smaller than the others and has many more secondary sensoria, being 

 a male. From this evidence this species is the same as Baker lists as 

 P. populifoliae (Fitch) and should be so considered. The author has 

 reared a number of specimens of a species of Aphidiiw from material 

 obtained near Stanford University in May, 1915. 



42. Pterocomma smithiae (Monell) 



Monell, U. S. Geol. Geog. Surv., Bull. 5, p. 32, 1879. Chaitophorus (orig. 



desc.). 

 Davidson, Jour. Econ. Ent., vol. 2, p. 300, 1909. Cladobius salicti (Harris) 



(list). 

 Davidson, Jour. Eeon. Ent., vol. 3, p. 375, 1910. Cladobius salicti (Harris) 



(list). 

 Essig, Pom. Jour. Ent., vol. 4, p. 786, 1912. Melanoxantherium salicti 



(Harris) (list). 

 Wilson, Ann. Ent. Soc. Am., vol. 8, p. 355, 1915 (desc.). 



Records. Salix spp., Stanford University (Davidson, Morrison). 



Both Davidson and Morrison have taken this species in the vicinity 

 of Stanford University on various species of willow. According to 

 Wilson, with whom Morrison and Baker agree, this is P. smithiae 

 (Monell), the salicti of Harris being synonymous. The sexuales were 

 observed by Davidson in October, the eggs hatching in January. 





Tribe Lachnini Del Guercio 



Del Guercio, Eedia, vol. 5, 1908. 



This tribe is represented in California by three genera, viz., Essig- 

 ella Del Guercio, Tuberolachnus Mordwilko, and Lachnus Burmeister, 

 while there are six genera included in the tribe as it is here considered. 

 Following is a brief characterization of the tribe adapted from Mord- 

 wilko : 



The body and appendages are very hairy, and usually quite large. The cauda 

 is absent, the cornicles cupola-shaped, being black or brown in color. Sometimes 

 they are reduced to mere pores or not fully developed [Lachnus taxifolia Swain]. 

 The antennae in general are not longer than the head and thorax, six- jointed 

 [except in Essigella Del Guercio], with the spur of the sixth segment very short, 

 not being as long as the segment itself. The beak is almost always elongated, 

 generally reaching to or beyond the middle of the abdomen. All this group possess 

 the anatomical peculiarity that the narrowed hind end of the stomach is covered 

 with the intestine. The stigma of the fore wing is elongate linear [in Longi- 

 stigma Wilson it reached past the tip of the wing (fig. 89)]. The cubitus is twice- 

 branched. 



