$,0. 1310. NORTH AMERICAN THYSANOFTERA—IflNDS. 207 



1.^ 



Frmalc. — Length about 4 mm. (3.34 to •i.2<) mm.); breadth of meso- 

 thorax 0.55 mm. (U.5(> to 0.(50 mm.). Color coal-blaek without mark- 

 ings. 



Head long" and cylindiical; proi)ortional length more \'aria])le than 

 in most species, but averaging about two and one-third times as long 

 a.s wide; surface of head transverseh' finely striated; cheeks set with 

 a number of short, stout spines; head In'oadened a trifle just before the 

 neck-like constriction at the l)ase; vertex produced into a very promi- 

 nent, conical hiuiip in front of the 03'es and overreaching the insertion 

 of the antenna*. Eyes large, finely faceted, bulging slightly, extend- 

 ing as far around on under side of head as on u])])er; ocelli small, 

 Avidely separated, the anterior one occupying the extreme vertex; the 

 posterior ones, nearly on a line Avith the middle of the eyes and close 

 to their margins, are often invisible, unless in favorable light, owing 

 to the opacity of the head. Mouth cone short and rounded. Antennae 

 approximate at base, inserted under the vertex, only about one and 

 one-sixth times as long as the head, and slender; relative lengths of 

 segments as follows: 



15 



Segment one concealed at base; three to five clavate; six to eight 

 fusiform. Three mostly yellow (two-thirds); four nearly one-half, 

 and five about one-third yellow; rest of antenna brown-black. Spines 

 and sense cones light and inconspicuous, but the cones especially are 

 long, slender, and acute; three apparently bears only one sense cone, 

 and that is on outer side; six has but one, which is on inner side; four 

 and live have four each. 



Prothorax small, only al)out two-tifths as long as head; only the one 

 long spine on the outer angle of each fore coxa is at all conspicuous. 

 Pterothorax appears nearly square; sides straight and parallel; more 

 than twice as wide as head. Wings present, but short as com]:)ared 

 with great length of abdomen, not reaching bej^ond fifth or sixth seg- 

 ment, heavily fringed; hind fringe of fore wing double for about 26 

 hairs near tip. Legs short as compared with length of body; fore 

 femora but slightly thickened and tarsi armed with a tiny tooth; legs 

 set with a number of quite long, slender, black spines. Legs black, 

 except fore tibiae dark yellowish brown along middle of inside, and 

 all tarsi dark brown. 



Al)domen extremely long and slender, about two-thirds the length 

 of the entire body and less than one-fourth as wide at base as it is 

 long; tapers gradually irom second segment to tube. Tube of female 

 fully five-sixths as long as head and a little moi'e than one-third the 

 width of head; terminal hairs weak and only about two-thirds the 

 length of the tube; spines on sides of abdomen short and weak. 



Redescribed from four females. 



