34 A CONTRIBUTION TO THE KNOWLEDGE OF 



Cryptoripersia arizonensis (Ehrh.). 



1899. Ripersia arizonensis Ehrhorn, Can. Ent., 31 :5. 

 1911. Eriococcus salinus Ehrhorn, Can. Ent., 43:276. 



1918. Cryptoripersia salinus (Ehrh.) ; Ferris, Cal. Species Mealy Bugs, p. 74, 

 pi. 3, fig. 30. 



Through the kindness of Mr. Ehrhorn I have been enabled to ex- 

 amine the type slides of both Ripersia arizonensis and Eriococcus salinus. 

 The two are certainly identical. I may record the species from the roots 

 of Elymus sp. at Fort Tejon, Cal. 



Genus ACLERDA Sign. 



Aclerda ariditatis n. sp. 



Fig. 15. 



Type host and locality. From a perennial grass, probably HUaria 

 cenchroides, on the Jornada del Muerto, fifty-one miles north of Las Cru- 

 ces, N. Mex. 



Habit. Occurring chiefly at the nodes of the stems, beneath the 

 sheathing bases of the leaves. Surrounded by a small amount of secre- 

 tion. 



Morphological characteristics. Length of adult female 2 mm. Form 

 elongate, nearly parallel-sided, sometimes somewhat irregular. Derm 

 membranous except for the posteriof portion of the abdomen, which is 

 heavily chitinized and presents a wrinkled appearance. Margin of the 

 body, except for this chitinized portion, beset with small, tubercle-like 

 spines (Fig. 15C), which are arranged in a single or irregularly double 

 row (Fig. 15H), their distance apart depending upon the age of the 

 insect and the consequent expansion of the derm, these spines rounded at 

 the tip, not pointed or "spearhead-shaped." Mingled with these spines 

 are a few large tubular ducts of the type shown in Fig. 15G and slightly 

 back from the margin is a row of such ducts (Fig. 15H) accompanied by 

 others of a much smaller size. On the chitinized portion of the abdomen 

 the large ducts are very abundant and are irregularly distributed. Anal 

 plate (Fig. 15F) entire, bearing several long setae. Ventral side of the 

 abdomen with a median furrow, which is continuous with the anal cleft, 

 and with the derm somewhat less wrinkled than on the dorsum. 



First stage (Fig. ISA, E) of the type common to the genus. 



Second stage ? Without appendages. Posterior end of the abdomen 

 (Fig. 15D) chitinized, marked with numerous wrinkles which are more 

 or less perpendicular to the margin. Anal cleft shallow, continuous with 

 a shallow furrow on both dorsum and venter. Anal opening at some 



