152 Annals Entomological Society of America [Vol. X, 



and Matsucoccus have been placed in a new sub-family Mar- 

 garodince. The common characters of the sub-family are, in the 

 female, the absence of legs and antennae in the intermediate 

 stages and of mouth-parts in the adult, in the adult male, the 

 presence of compound eyes. The following table will assist in 

 the identification of the North American species of Xylococciis. 



I. In first larval stage one median ventral pore. 



In apodous stages anal tube without median circles of spinnerets. 



niacrocarpcE Cole. 

 II. In first larval stage more than one median ventral pore. 



In apodous stages anal tube with median circles of spinnerets. 



a. Anal tube with one median circle of spinnerets. Five median ventral 



pores betiilce Perg. 



b. Anal tube with two median circles of spinnerets. Median pores varying 



from 2 to 4 quercus Elir/i. 



c. Anal tube with three median circles of spinnerets. Median pores 



varying from 6 to 7 ; alrii n. sp. 



Xylococcus macrocarpae Cole. 



Eggs. — Length, .55 mm., diameter, .275 mm.; oval, highly polished; 

 colour pale lemon 3^ellow. 



Larva, first stage. — Length about .7 mm., diameter about .3 mm. 

 Color on hatching very pale yellow, later becoming tinged with red. 

 Shape oblong-oval, sides sub-parallel narrowing a little posteriorly. 

 Segments all well defined. Eyes black, situated on prominences lateral 

 and posterior to antennae (PI. XIV, fig. le). Antennae six-jointed, 

 short, stout; fonnula 6, 1, 2, 5, (3, 4); joint one stoutest, joints two to 

 five approximate!}' equal in diameter, last joint slender; all joints 

 except three and four bearing hairs that increase in length towards 

 apex; on joint five at base of exterior lateral edge a stout spine; on joint 

 six a ring of four stout spines and a single spine on apex; a very long 

 bristle at aj^ex; a single pore on joint two (PI. XIV, fig. 1). Legs 

 long and stout; tarsus longer than tibia; a ring of pores, one long hair and 

 one short one on trochanter; digitules on tarsus fine tmknobbed hairs, 

 on claw knobbed hairs (PI. XIV, fig. 2). Rostrum large, situated 

 about middle of body; sucking bristles very long. Anal tube rather 

 short and broad, formed by an extension of the outer walls of a circle 

 of chitinous spinnerets which surround and open into the posterior end 

 of the alimentary canal. Spiracles, two pairs on thorax, eight pairs 

 on abdomen; the former inconspicuous, the latter \vith well developed 

 stigmatal tubes (PI. XIV, fig. 3). Body with hairs sparsely scattered 

 over cephalic and thoracic areas, and on dorsal and ventral surfaces 

 of abdomen in transverse rows, one on each segment; a pair of backward 

 directed short lateral spines on each abdominal segment; on ventral 

 surface of segment eight single long lateral bristles ; pores of three types ; 

 a simple median ventral pore anterior to anal tube; compound lateral 

 pores on each thoracic and first seven abdominal segments dorsally and 

 ventrally; small pores as follows — a pair on cephalic area anterior to 

 pro thorax, a pair on the meso thorax, a pair on the metathorax, a pair 



