80 REPORT UPON A COLLECTION OF 



Genus XEROCOCCUS n. gen. 



Coccidae referable to the subfamily Dactylopiinae (of the Fernald 

 Catalogue) and belonging probably to the Eriococcus group, that is with- 

 out dorsal ostioles, with tubular ducts which have the inner extremity 

 of the basal portion reflexed into a cup and with the anal ring bearing 

 setae. Adult female with the antennae reduced to mere vestiges and 

 with the legs represented by minute chitinized points ; body terminating 

 in a pair of large, swollen lobes ; anal ring non-cellular, bearing six smail 

 setae; tubular ducts numerous, of the ordinary Eriococcine type. Inter- 

 mediate stages resembling, in general, the adult. First stage with the 

 antennae 6-segmented, of the usual Eriococcine type ; anal ring very small 

 and apparently the same in form as that of the adult; dorsum without 

 spines, margins of the abdomen with short, stout spines. 



Type of the genus Xerococcus fouquieriae n. sp. 



Notes: This genus departs rather widely from the usual Eriococcine type, 

 yet it appears to belong to this group. I know of nothing that very closely re- 

 sembles it. 



Xerococcus fouquieriae n. sp. 



Fig. 8. 



Type from Fouquicria peninsularis ("palo de Adan") at La Paz. 



Habit. Occurring beneath the bark scales of the host, imbedded in a 

 considerable amount of amorphous secretion ; insects of a bright red 

 color in life. 



Morphological characteristics. Adult female (Fig. 8A) about 2.5 

 mm. long (on slide), elongate-oval, tapering posteriorly, the body terminat- 

 ing in a pair of large, swollen lobes. In fully mature individuals the 

 derm becomes quite heavily chitinized throughout, but in younger 

 examples only the posterior portion of the abdomen and the lobes are 

 chitinized, these heavily so. On the anal lobes and the posterior portion 

 of the abdomen the derm presents a somewhat papillate appearance. 

 Antennae (Fig. 8E) very small, consisting of three minute segments. 

 Legs represented by small chitinized points. Derm almost destitute of 

 setae except for a few that are extremely small and slender. Anal ring 

 (Fig. 8D) quite small, almost concealed between the lobes, simple and 

 bearing six small spines. Derm with large numbers of tubular ducts 

 (Fig. 8F) which bear internally a filamentous prolongation and have the 

 larger basal part terminating in a reflexed, somewhat asymmetrical cup. 

 Spiracles (Fig. 8B) rather small, surrounded by many small ducts with a 

 trilocular center (Fig. 8C). 



