SYSTEMATIC TREATMENT 65 



ceanothi, established by Cockerell because of the "considerably longer second and 

 fourth joints of the antennae," is hardly to be taken seriously. Among the ma- 

 terial of Pseudococcus agrifoliae received from Mr. Essig is a slide labeled "co- 

 type" which contains specimens of larvae of a Puto taken from Quercus agrifolia 

 near Claremont. It is impossible to identify these specimens with certainty, but 

 it is possible that these are P. yuccae. 



Genus HETEROCOCCUS new genus 



Pseudococcine forms with quinquelocular dorsal pores instead of the 

 usual triangular pores ; with cerarii on the posterior portion of the ab- 

 domen only; with a more or less distinct denticle on the tarsal claws; 

 with 9-segmented antennae in the adult female. 



Type of the genus Heterococcus arenae n. sp. 



Notes: Morphologically the species upon which this genus is based seems 

 to belong to the Phenacoccus series, the 9-segmented antennae and the presence 

 of a denticle on the claw being indicative of this. However, the presence of circular 

 dorsal pores is quite distinctive. It is possible that Pseudococcus poae (Maskell) 

 is congeneric with this, for it is said in the original description of that species that 

 "All over the body are small circular spinnerets." Otherwise I know of no similar 

 species. 



Heterococcus arenae n. sp. 

 Text figure 16C ; plate 3, fig. 32. 



In life. Found beneath the leaf sheaths of its host, where it is sur- 

 rounded by a small amount of secretion. 



Morphological characteristics. Cerarii present on the last two ab- 

 dominal segments only ; each with two slender and rather long spines 

 which are distinguishable from the body spines only by their position and 

 paired character ; without grouped pores. Anal lobe cerarii accompanied 

 by a few spines which are as large as the cerarian spines. Dorsal body 

 setae slender, scattered, ventral body setae few, slender. Dorsum with 

 numerous pores, all of which are circular and quite large. Tubular ducts 

 few and very small, all without a raised rim about the mouth. Tarsal 

 claws typically with a denticle, although in some specimens this appears 

 to be lacking. Anal ring large. Anal lobe setae slightly longer than the 

 anal ring setae. Antennae of the adult female 9-segmented. 



Immature female differing from adult only in reduction of number 

 of antennal segments. 



Type host and locality. From Poa douglasii, on the sand dunes near 

 Asilomar at Pacific Grove, Monterey County, Calif., December 1, 1917. 



Hosts and distribution. Known only from above host and locality. 



