A SYNOPSIS OF THE APHIDIDAE 47 



45. Lachnus ferrisi Swain 



Figures 89, 91 



Davidson, Jour. Econ. Ent., vol. 2, p. 299, 1909. Lachnus abietis Fitch 



(list). 

 Davidson, Jour. Econ. Ent., vol. 3, p. 374, 1910. LacUnus dbietis Fitch 



(list). 



Essig, Pom. Jour. Ent., vol. 4, p. 773, 1912. Ladhnus abietis Fitch (list). 

 Swain, Trans. Am. Ent. Soc., vol. 44, p. 9, 1918. 



Records. Abies concolor, Stanford University (Davidson) ; Pinus sp., Stan- 

 ford University (Swain). 



This large lachnid, recently described by the author, has been 

 found only in the vicinity of Stanford University, in 1909 and 1910 

 by Davidson on lowland fir, and in 1915 by Ferris on some young 

 pine trees. Since then it has not been observed. 



46. Lachnus glehmis Essig 



Figures 96, 97 



Essig, Pom. Jour. Ent. Zool., vol. 7, pp. 180-187, 1915 (orig. desc.). 

 Eecord. Picea glehni, Sacramento (Essig). 



Essig described this species from specimens taken on a Japanese 

 spruce in Capitol Park, Sacramento, in 1912. At the time it was so 



abundant that control measures were deemed necessary. The author 



\ 



has had access to the type specimens in Essig 's collection. 



47. Lachnus occidentalis Davidson 



Davidson, Jour. Econ. Ent., vol. 2, p. 300, 1909 (orig. dese. apterae). 

 Davidson, Jour. Econ. Ent., vol. 3, p. 374, 1910 (list). 

 Essig, Pom. Jour. Ent., vol. 4, p. 773, 1912 (list). 

 Wilson, Can. Ent., vol. 44, p. 193, 1912 (desc. all forms). 



Records. Abies grandis, Stanford University (Davidson, Morrison, Ferris 

 and the author) ; Abies concolor, Corvallis, Oregon (Wilson). 



This species is practically always present on a lowland fir tree in 

 the cactus garden of the Stanford University grounds. Wilson has 

 found it in the vicinity of Corvallis, Oregon, on white fir. Davidson 

 states that it is heavily preyed upon by the larvae of Syrphus arciuvtus 

 and Syrphus opinator. 



