58 A CONTRIBUTION TO THE KNOWLEDGE OF 



Xerophilaspis prosopidis Ckll. 

 Fig. 31. 



Type host and locality. From Prosopis, near Phoenix, Ariz. 



Material examined. From Prosopis velutina, near Tucson, Ariz., 

 and from undetermined host (probably Prosopis sp.), San Diego, Cal. 



Scale. Scale of the female circular, composed almost entirely of 

 the hardened, jet-black second exuvium. Covering this exuvium is a very 

 thin, white secretionary scale which is so transparent that it is frequently 

 practically invisible. First exuvium naked. Before the hardening of 

 the second exuvium the white secretionary scale is plainly visible. It is 

 perhaps this stage which Cockerell has described as the scale of the male, 

 although he has himself stated that he had described the male of Aspid- 

 iotus candidulus as the male of X. prosopidis. I have not myself seen the 

 male. 



Fig. 31. Xerophilaspis prosopodis Ckll.: A, adult female; B, pygidium of adult 

 female; C, margin of pygidium of early second stage; D, antenna of first 

 stage. 



Female. Adult female (Fig. 31 A) more or less circular in form, 

 with the anterior end produced into a rounded projection; derm of the 

 cephalothorax (which comprises far more than half of the body) heavily 

 chitinized, especially in the anterior part. Pygidium (Fig. 31B) with 

 two pairs of small lobes and with several submarginal spines, entirely 

 without plates. Tubular ducts extremely small, arranged in a narrow, 

 transverse belt at some distance from the margin and on a line passing 



