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other places are mere spots of the longitudinal stripes, or, sometimes, together form regular 
horizontal stripes. In very young specimens the spots and stripes are often very distinct. The 
compartments are longitudinally ribbed along the inner side, and have no pores. Basis with 
delicate canals radiating from the centre. Radii very narrow, with the summits oblique, and 
no pores. Alae broader with the upper margins rounded. 
The scutum (Pl. XVII, fig. 8, @ and c) has narrow and numerous growth-ridges and 
longitudinal striae crossing the growth-ridges, delicate but distinct, in the larger specimens 
especially. The striae are more distinct than in &. aldus and tenuis, but not quite so pro- 
minent as in 2B. amaryllis and B&B. bdimae. The articular ridge is well-developed, extending 
slightly over half the length of the tergal margin; adductor ridge rather prominent, but only 
in the superior half of the valve; pit for the depressor muscle rather large and distinct. 
The tergum (Pl. XVII, fig. 8, 4 and d) has the scutal margin distinctly hollowed 
out, and the apex beaked. The spur is short and broad; its extremity is cut off obliquely, its 
posterior margin going over almost insensibly into the basal margin of the tergum. The distance 
of the spur from the basi-scutal angle is shorter than the width of the spur. There is no longi- 
tudinal furrow. The crests.for the depressor muscles are moderately developed; numerous longitu- 
dinal and parallel ridges occupy the interior surface between the occludent margin and the spur. 
The larger specimens measure at the basis 10.5 to 12 mm.; their height is about 
7 mm. Most specimens are, however, much smaller. 
With regard to the structure of the animals body, the following may be of interest: 
Mouth. Labrum (Pl. XVII, fig. 9) with the notch not very deep, wide at entrance 
and 3 well-sized teeth on each side, standing close together. In one instance, two teeth were 
seen on one side and three on the other. Lateral parts with the upper margin rounded; the 
interior terminal part of the sub-triangular portion relatively narrow. 
Palpi nearly quadrangular, or elongately-quadrangular, with the upper margin straight, 
only slightly hollowed out in the middle, the inferior margin distinctly convex, gradually going 
over in the distal margin, which makes an angle with the upper margin. A dense row of 
short hairs disposed in several rows along the upper margin. The outer surface, near the angle 
where upper and distal margins meet, is furnished whith a dense group of longer hairs, which 
together form a tuft, extending far beyond the shorter hairs arranged along the upper margin. 
This group of longer hairs occupies an almost triangular corner of the outer surface, and terminates 
with a row of similar hairs, which make an angle with the basal margin of the palpus; the 
inferior part of the outer surface without hairs. The distal margin is furnished with only a few 
microscopical hairs. The inner surface is furnished with shorter and curled hairs; a longitudinal 
row of such hairs is inserted parallel to a fold or rim which, if the palpus is not elevated, 
extends along the free margin of the labrum. 
Mandible (Pl. XVII, fig. 10) with the first and second teeth sharply pointed, the 
third slightly shorter and blunt. Teeth 2 and 3 indistinctly double at the extremity. The distance 
between the extremities of teeth 2 and 3 nearly equals that between teeth t and 2. Fourth 
tooth small, fifth rudimentary, the part of the mandible behind the 3*¢ tooth small. 
Maxilla (Pl. XVII, fig. 11 and 11*) short, edge relatively long, shape triangular. 
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