SYSTEMATIC TREATMENT 39 



Pseudococcus azaleae (Tinsley). 



1898. Dactylopius azaleae Tinsley, Can. Ent. 30:319. 



1914. Pseudococcus azaleae (Tins.) ; Essig, Mon. Bull. Calif. State Com. Hort. 

 3:108. 



This species was originally described from specimens taken from 

 azalea in a Japanese nursery at San Jose. It is not now known to occur 

 in this state and is not here considered. 



Pseudococcus citri (Risso). 

 Plate 1, figs. 7, 9. 



1910. Pseudococcus citri (Risso.) ; Essig. Pomona Col. Jn. Ent. 2, no. 4:289-320, 



figs. 111-119. 



Note : The literature in regard to this species is so voluminous that only the 

 reference to the above admirable article is given. 



In life. Covered with thick white cottony wax, the marginal tassels 

 short but distinct, becoming somewhat longer posteriorly with the caudal 

 pair equaling perhaps one-fourth the length of the body. Eggs deposited 

 in large, more or less irregular masses. 



Morphological characteristics. With 17 pairs of cerarii, none of 

 which contain more than two conical spines, these quite large, the anal 

 lobe pair not exceeding in size those preceding it. All the cerarii without 

 auxiliary setae and with very few pores. Anal cerarii without a definite 

 chitinized area, but occasionally showing a very slight chitinization. 

 Ventral side of each anal lobe with a narrow, very distinct, chitinized 

 area extending in from the base of the anal lobe seta and bearing a small 

 hair at about midway of its length. Dorsal body setae scattered, quite 

 small and slender. Cylindrical ducts very few in number, of the small 

 type, without raised rim at the mouth. Anal lobe setae somewhat longer 

 than anal ring setae. 



Immature female differing but little from the adult. 



Hosts and distribution. In the northern part of the state this species 

 appears to be confined to greenhouses, although I have at hand specimens 

 taken from citrus at Marysville. In the vicinity of Stanford University 

 it does not appear to live out of doors. Its distribution and status in the 

 southern part of the state are too well known to require comment here. 



Authentication. Common repute. 



Notes : The only California species with which this is likely to be confused 

 are P. krauhniae (Kuwana) and P. eriogoni (Ehrh.). It is indeed very similar 

 to the former, but may readily be distinguished by the fact that the tips of none 

 of the spines are prolonged into a sort of flagellum and by the much scantier cov- 

 ering of hairs. From the latter it may always be distinguished by the presence 

 of cerarii between the eyes. 



