22 PROC. ENT. SOC. WASH., VOL. 23, NO. 1, JAN., 1921 



First stage larva. Body elongate, .5 mm. in length when full grown, with sides 

 nearly parallel and caudal end abruptly acute. (PI. Ill E.) In lite of a brownish 

 color and surrounded with rays of wax. Head separated from and distinctly 

 narrower than rest of body, and with prominent eyes. Antennae 6-segmented, 

 bases well separated: segment 1 rather large and broad, 2 long without spines or 

 setae, 3 very short, 4 long, bearing 1 broad stiff spine, 5 medium, 6 very long 

 bearing 2 broad stiff spines and a small nipple-like process on its tip. Legs 

 rather small, femur broad, tibia, tarsus and claw slender, the latter bearing 2 

 knobbed digitules. Trochanter bearing 1 long slender seta. Segmentation of 

 abdomen distinct. Spiracles each on a raised process, together resembling a 

 row of buttons on each side of abdomen; also a very small transparent pore 

 dorsad of each spiracle. Tip of abdomen rounded, bearing a short and a long 

 slender seta on each side of apex. Dorsum somewhat chitinized. First exuvium 

 rupturing on dorsum. 



Male. Unknown. 



Types. Holotype, an adult female, and paratypes of adults 

 and larvae from exposed portions of the needles of the single-leaf 

 pinon (Pinus monophylla) from southern Idaho. Holotype and 

 paratypes in the Entomological Collection at Stanford Univer- 

 sity. Paratypes also in the National Collection of Coccidae 

 and the Forest Insect Collection at Los Gatos, California. 



This material was received by Prof. R. W. Doane from Mr. 

 P. J. O'Gara several years ago, simply with the information 

 that it was apparently doing some damage in Idaho and request- 

 ing a determination. It was recently inspected by Mr. G. F. 

 Ferris, who, upon finding it to be a Matsucoccus, kindly turned 

 it over to the author to be described with the request that the 

 type be deposited in the Entomological Collection at Stanford 

 University. This has been done. To the above mentioned 

 gentlemen the fullest thanks are due for the privilege of describ- 

 ing this species. 



EXPLANATION OF PLATE III. 



A. Section of Pinus rigida twig showing pits or galls containing immature forms 



of M. mastumurae. 



B. First stage larva of M. matsumurae. 



C. Apodous larva of same. 



D. Immature forms of M. acalyptus, n. sp., on needles of Pinus monophylla. 



E. First stage larva of same. 



F. Apodous larva of same. 



G. Adult female of same showing tracheal system. 



H. Top view and cross-section of spiracle of apodous larva of M. acalyptus. 

 I. Same of M. mastumurae. 



J. Cross-section of internal duct of M. matsumurae and top view of same, show- 

 ing 8-shaped pore surrounded with compound ring. 



All greatly enlarged, the early stages more than the later stages. Drawn by 

 F. B. Herbert. For illustrations of adult legs, antennae, etc., see Plates XIII 

 and XIV, Proc. Ent. Soc. Wash., Vol. 21, No. 7 (Oct., 1919). 



