August, '15] 



DAVIDSOX: WESTERN PLANT-LICE 



427 



Smaller and more blunt tubercles occur on the sides of segments 3 to 6 inclusive, but 

 these are not very obvious. Cornicles hyaline, ahnost twice as long as broad, some- 

 what constricted in the centre. Cauda globular, pale green, longer than the cornicles 

 and thickly beset with bristles. Anal plate deeply cleft, spinous, pale gi^een. Beak 

 pale, extreme tip bro^\'n, almost reaching the second pan of coxae. 



The three pairs of dorsal tubercles in living specimens appear white. 

 The two abdominal pairs are about three times as long as the meso- 

 thoracic pair and of them the pair on the second segment is the longer. 

 In living examples the whole body has many delicate pruinose mark- 

 ings. The areas of darker green occur mostty about the base and 

 along the sides of the abdomen. 



The insect is noticeably narrow-bodied and occurs on the under side 

 of the leaves of tan-bark oak {Pasania densiflora Oerst.). The pupa 

 is of the same color as the winged female, but is shorter and more 

 robust. Dates of collection and localities for the winged viviparous 

 female are as follows: Berkeley, CaL, June 12, 1914; Congress Springs, 

 Cal., November 6, 1914; Berkelej^ CaL, February 17, 1915. The tan- 

 bark oak is an evergreen tree. 



Measurements; Length of body, 2.04 mm. to 2.60 mm. Max. width of body, .73 

 mm,, to .97 mm. Cornicles, .09 to .12 mm. Cauda, .17 to .19 mm. Wing expanse, 5.7 

 mm. Antennae I, .078 mm.; II, .05 mm.; Ill, .72 to .87 mm.; IV, .60 to .70 mm.; 

 V, .53 to .59 mm. ; VI, .26 to .29 mm. Filament, .29 to .31 mm. 



Macrosiphum heucherce Thomas 



Siphonophora heucheros Thos. Thomas, 8th Rept. 111., Xox. Ben. Ins., 1880. 



Apterous viviparous female. — General color dark reddish-bro\\Ti. Eyes red. An- 

 tennae and cornicles black. Cauda reddish-bro'^ii. Legs black, basal third of femora 

 and median portion of tibiae reddish-bro^-n. Antennae about equal to the body in 

 length, on shghtly gibbous frontal tubercles. Filament of VI longer than III; IV 

 and V subequal. Cornicles cyhndrical, imbricate but not reticulate. Cauda ensi- 

 form, twice as long as broad at base. Body sparsely armed with short hairs. Sen- 

 soria cncular tuber culate, about 26 on III, 7 on IV, 2 beside usual apical on V. One 

 specimen has the joints III to V inclusive all fused together. Measurements : Length, 

 2.13 mm. Max, width (3d. abd. seg.), 1.00 mm. Hind tibia, 1.64 mm. Cornicles, 

 .34 mm. to .40 mm. Cauda, .233 mm. Beak, .58 mm. Antennae III, .53 mm.; IV, 

 .355 mm.; V, ,355 mm.; VI, .12 mm. Filament, .70 mm. Beak reaches beyond 

 second coxae. 



Winged viviparous female. General color dark green. Wing insertions and iU- 

 defined spots on the sides of the abdomen brick-red. Disk of abdomen with a large 

 dusky spot. Head, thorax and cornicles black. Antennae black, base of III green. 

 Cauda reddish-bro^-n. Eyes dark red. Stigma gray, long and narrow. Legs 

 black, basal foiuth of femora and tibiae except the apex pale greenish-yeUow. Anten- 

 nae on frontal tubercles a httle exceeding the body in length, filament longer than III, 

 IV and V subequal. Cornicles cyhndrical. Cauda ensiform. Beak reaching to 

 middle coxae. Sensoria circular tuberculate, about 39 to III, 22 on IV, 7 on V. One 

 specimen has the antennal joints III, IV, V fused together so that the articulations 

 are not discernible. Measurements: Length, 2.18 mm. Max. width (thorax) .83 



