34 



SCALE INSECTS OF SANTA CRUZ PENINSULA 



emarginate at the tip. The anal ring lies directly beneath the anal plate. 

 The ventral furrow is open, its margins diverging anteriorly and not 

 heavily chitinized. 



Fig. 14. Aclerda tokionis (Ckll.) : A, dorsal aspect of posterior extremity of ab- 

 domen of adult female ; B, marginal spines ; C, anal plate. From California 

 material. 



Genus PULVINARIA Targ. 

 Pulvinaria ehrhorni King. 



Originally described from this area, from alder and willow. It is 

 apparently rather rare, as I have obtained but a single specimen in five 

 years of collecting. Presumably native. 



The single specimen available shows some indications of abnormality 

 and is hardly suitable material upon which to base a re-description. I 

 may note, however, that while the species in life resembles P. vitis it is 

 evidently distinct, as the marginal spines are filiform. In this respect it 

 somewhat resembles P. rhois, differing however, from the latter in having 

 the derm of the dorsum heavily chitinized instead of membranous. In 

 certain respects it appears to resemble P. amygdali Ckll. 



Pulvinaria rhois Ehrh. 



Fig. 15. 



Described from this area. As far as known it occurs only on the 

 "poison oak," Rhus diversiloba. I have seen specimens taken from this 

 host at Walnut Creek, Contra Costa County, California. The species is 



