287 



triangular spots united basally on middle of pronotum, a large quadrangular spot on 

 middle of mesonotum, one row of small spots on each side of the dorso-meson on the 

 segments posterior to this, another row along each side margin of all the dorsal seg- 

 ments, and a few smaller spots between the middle abdominal terga, together with 

 cornicles, black ; coxa? dusky ; trochanters and femora, except tips, reddish brown; 

 tips of femora, together with tibije and tarsi, black, except that the middle of the 

 tibia is often reddish-brown. Cornicles very short, conical, truncate. Ventral sur- 

 face dusky, with a glaucous bloom. Rostrum dusky, reaching posterior cox:«. Body, 

 legs, and antennae furnished with rather long, light-brown hairs. Anteunse rough- 

 ened ; joint III very long, equal to iv plus V, the latter being subequal, though V is 

 slightly longer than iv ; vi short, with a well developed thumb, forming vii ; v 

 slightly enlarged near tips by a distinct sensorium ; and another on vi at the base of 

 the projecting thumb. 



Winged Viviparous Female. (Plate 1, Fig. '.i, 3a). — Body 6 millimeters long, by 

 3.5 millimeters wide across middle of abdomen; head to tip of folded wings, 10 milli- 

 meters; wing expanse, 18 millimeters; antennae, 3 millimeters; posterior legs, 11 

 millimeters. 



Head and thorax bluish-black with a glaucous bloom ; antenn;© and cornicles 

 black ; dorsum of abdomen whitish, with two rows of black spots on each side of 

 median line, and a transverse series of small, black, indented dots on each segment. 

 Cornicles short, conical, truncate. Ventral surface of abdomen yellowish-brown, 

 with a glaucous bloom. Coxae concolorous with thorax ; trochanters and femora ex- 

 cept tips, reddish-brown ; tips of femora, together with tibiae and tarsi, black. 

 Rostrum dusky, reaching posterior coxae. Body, legs, and antenniB clothed with 

 rather long, light brown hairs. Joints of antennae of same relative length as in ap- 

 terous viviparous form. Wings clouded, especially towards base ; insertions reddish- 

 brown; veins piceous. 



Oviparous Female. — This form does not differ in external appearance from the 

 apterous viviparous female. 



Winged Male (Plate 1, Fig. 1, la). — Body 5 millimeters long, by 2 millimeters 

 wide, across middle of abdomen; head to tip of folded wings, 9 millimeters; wing 

 expanse, 16 millimeters ; antennae, 2.4 millimeters ; posterior legs, 8 millimeters. 



Head and thorax bluish-black, with a glaucous bloom ; antenuje piceous ; eyes 

 black. Abdomen small, dorsum whitish, but nearly covered with two rows of large 

 black spots on each side of dorso-meson, and having transverse rows of less distinct 

 indented black dots. Ventral surface of abdomen yellowish-brown, with a glaucouf 

 bloom, except posterior extremity, which is black. Coxae concolorous with thorax ; 

 trochanters and femora, except tips, reddish-brown ; tips of femora together with 

 tibite and tarsi black. Rostrum dusky, reaching slightly behind posterior cox;b. 

 Cornicles black, conical, truncate. Body, legs, and antenme clothed with rather long, 

 light-brown hairs. Antennae roughened ; joints of same relative length as in apter- 

 ous viviparous female. Eyes as seeu from above subtriangular in form. Wingf 

 clouded ; insertions light yellowish-brown ; veins piceous. 



The Egg (Plate 1, Fig. 4). — Length, 1.8 millimeters ; width, 0.5 millimeter. Elon- 

 gate-ovoid. Orange-brown at first, but changing on exposure to shining black. 

 Covered when first laid with a viscid substance by which it is securely attached to 

 the bark of the twig or limb. Great numbers deposited together. 



The Box Elder Chaitophorus {Chaitophorus negundinia Thomas). 



This species has been abundant the past season on certain trees in 

 this vicinity. After the leaves fall off the insects congregate upon the 

 twigs where the eggs are deposited. The sexed forms ai)pear early in 

 October. The male is apterous, and is represented magnified at a, Fig. 

 23. The oviparous female is shown at h of the same figure, while the 

 eggs are represented at c and d. 



