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other places are mere spots of the longitudinal stripes, or, sometimes, together form reo-ular 

 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 (PI. XVII, fig. 8, a 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 B. albus and tennis, but not quite so pro- 

 minent as in B. amaryllis and B. bimae. 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 (PI. XVII, fig. 8, ó 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 (PI. 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. 



Pal pi 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 (PI. XVII, fig. 10) with the first and second teeth sharply pointed, the 

 third slightly shorter and blunt. Teeth 2 and 3 indistinctly doublé at the extremity. The distance 

 between the extremities of teeth 2 and 3 nearly equals that between teeth 1 and 2. Fourth 

 tooth small, fifth rudimentary, the part of the mandible behind the 3 rJ tooth small. 



Max il la (PI. XVII, fig. 11 and 11*) short, edge relatively long, shape triangular. 



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