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The scutum (PI. XVIII, fig. a and c) has the occludent margin arched, and the tergal 

 and basal margins of about the same length ; there is no adductor ridge, and the articular ridge 

 is feebly developed, not at all prominent. On the outer surface the growth-ridges are not very 

 distinct, and no tracé of striae can be observed. The whole surface is slightly arched, the 

 apex curved inwards. 



The tergum (PI. XVIII, fig. b and d) has the scutal margin slightly convex, and the 

 basal margin concave. The outer surface does not show the growth-ridges even so well as 

 the scutum. The spur extends slightly beyond the basal margin, and is rather broad; its anterior 

 margin is separated from the basi-scutal angle by a very short anterior part of the basal margin ; 

 in other specimens, however, it is confluent with the scutal margin. Crests for the depressor 

 muscles well-developed. The chitinous membrane covering the tergum bears a distinct group 

 of short hairs along the carinal margin, near the apex. The latter is blunt, not produced. 



With regard to the structure of the animal's body, the following was observed : 



Mouth. Lab rum (PI. XVIII, fig. 15). The normal number of teeth on each side of the 

 wide notch seems to be 3. Often, on one, or on both sides, only two of these are developed, 

 in which case one of the teeth may be double-pointed. The subtriangular portion representing 

 the thickened part of the labrum terminates on the inside in a somewhat narrower part, looking 

 like a handle. 



Pal pi with numerous hairs scattered irregularly over large part of outer surface. There is 

 no distinct tuft of longer hairs disposed at the distal extremity of the palpus. Shape of the 

 palpus oval, with the inferior margin distinctly rounded. 



Mandible (PI. XVIII, fig. 16) with teeth 2 and 3 doublé, and 3 thicker. Distance 

 between extremities of teeth 1 and 2 slighty longer than that between the extremities of teeth 

 2 and 3. The part behind the 3 rd tooth rudimentary: teeth 4 and 5 small, the inferior angle 

 represented only by a minute point. 



Maxilla (PI. XVIII, fig. 17) with the edge nearly straight, a small and shallow notch 

 behind the upper pair, and 3 to 5 somewhat shorter spines situated between this notch and the 

 inferior pair. The notch is narrower in some specimens than in others ; as a rule one or two 

 hairs are seen at the bottom of the notch. 



Outer maxi 11 ae (PI. XVIII, fig. 18). Outer lobe relatively broad and short, obtusely 

 pointed, and with the inner margin more or less straight. A moderate portion of the inner 

 surface of the outer lobe is covered with hairs, from which a single or doublé row can be foliowed 

 to the inner lobe. The latter is somewhat elongated towards the basis, the hairs disposed 

 along its inner surface point towards the basis of the maxilla; they are more distinctly feathered 

 than those of the remaining parts of the maxilla. 



Cirri. First pair has the rami unequal, of 6 to 7, and 11 to 12 segments. Anterior 

 faces of the segments of shorter ramus rounded, not protuberant. 



Second pair has 7 to 8, and 8 to 9 segments in the two branches. The anterior 

 faces of the segments protuberant, furnished with dense brushes of hairs. 



Third pair has 9 to 10, and 10 to 11 segments. Brushes of hairs less dense than on 

 the protuberances of the segments of the second cirrus. No tracé of teeth on or along the 



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