86 INDEX TO MISSOURI ENTOMOLOGICAL REPORTS. 



longitudinal suture, and a transverse one dividing it in two, the anterior half pale, 

 the posterior darker; the metathoracic portion showing a sub-triangular scutel, and 

 separated from mesothorax by the transverse baud (apodema of Targioui). Wings 

 about as long as body, arising from base of mesothorax, spatulate, closing tlat on back 

 in repose, and appearing whitish, finely and uniformly covered with short, stiff hairs; 

 supported, by a bifurcate vein, the bifurcation arising from basal fourth, and each 

 fork running near and almost parallel with the wing-margins; balancers dark, with 

 the hook quite long. Legs with the middle pair longest, and from large size of cox;e 

 further from front than from hind pair ; the cox;e and femora large and swollen, the 

 latter with a more or less distinct lobe near the base below; the tarsi one-jointed, 

 with a constriction occasionally indicated, and terminating in a single flexible claw, 

 surrounded by four clubbed hairs; the tibue and tarsi are quite bristly, but on the 

 femora there are usually but two bristles, one about the middle above, and one on the 

 basal lobe below; the coxre also have one above. Abdomen, seen from above, nearly 

 as long as thorax ; appearing shorter from below; 8 joints only discerned ; the last 

 joint abruptly narrowed into a large tubercle bearing four bristles on the under side, 

 and sending forth the genital armor in the form of an awl-shaped style as long as the 

 abdomen. 



$ Scale Larval part golden yellow; the anal shield yellowish-brown, sometimes 

 quite pale, inclining to white, flattened, straight, rather more than twice the length 

 of larval scale, increasing in width from tip to end, where it is slightly truncate; at- 

 tached by a white film ; average length, 0.035 inch. 



9 Average length, 0.05 inch; color, pale yellow; jug-shaped and flattened when 

 young, more globular when mature, and twice as long as wide ; the cephalo-thoracic 

 portion rounded and entire, but narrower than the abdominal, at the juncture with 

 which it forms a more or less conspicuous lateral projection ; on its inferior side is a 

 tubercle, having two longitudinal ridges, and giving rise to a corneous, filiform pro- 

 boscis, longer than the body, and composed of four separate parts ; posterior abdomi- 

 nal joints deeply lobed laterally, with two or three blunt, fleshy hairs to each lobe; 

 anal plate gamboge-yellow, corneous, with an irregular border, presenting two larger, 

 slightly tri-lobed, median projections, and one or more smaller ones each side, fur- 

 nished with spinous hairs, two especially between the tri-lobed projections aforenamed ; 

 five more or less complete sets of secretors visible from below, arranged around anus 

 in form of an arc, the median set with normally 10, the upper laterals 20, and the lower 

 laterals 14 ; besides these, some six or more blunt tubes, and a series of shorter pointed 

 ones, may be noticed along the border, and doubtless serve as secretors. (See Fig. 32 &.) 



9 Scale Larval scale golden-yellow ; median scale somewhat darker; anal shield 

 varying from pale brown to deep purplish-gray, and generally of a color with the bark 

 it is upon. The whole scale is often iucauous, but the hoary film easily rubs off; it 

 averages 0.12 inch in length, but is quite variable in form and size, being either straight 

 or curved, narrow and strongly arched, or broad and flatter, but always rounded at 

 the end ; the white inferior laminne at sides sometimes show distinctly from above, and 

 give the appearance of a pale border. 



The lice, whether $ or 9 , vary in appearance according to position and state of ma- 

 turity. In making the foregoing descriptions and figures, I have taken what appeared 

 the most natural positions, after examination of many specimens. The $ abdomen 

 shrinks very much in drying, and the more detailed 9 characters are variable. While 

 the normal number of secretors in the middle set is never more than 10, I have some- 

 times found but 8 or 9 ; that of the upper laterals never surpasses 20, but may be as 

 low as 15 ; while that of the lower laterals is more uniformly 14, though I have some- 

 times found 16, and at others 12. Opposite sets do not always contain the same num- 

 ber. [Fifth Rept., pp. 95-96. Figs. 31, 32. 



This is the species previously known us Aspidiotus conchiformis, or 

 popularly as the Oyster-shell Bark-louse, and the reasons for separa- 

 ting it are given in the report. 



