224 kobert h. wolcott: 



extreme width at a point a short distance beyond the middle is equal to 

 two-thirds of the length; from the side the dorsal convexity is seen to be 

 considerable and quite uniform, but highest posteriorly. Its surface is 

 smooth and without chitinous thickenings or lines of any kind, though 

 the epimera show the regular reticulation referred to in regard to the 

 two preceding species. 



Eyes as in the two preceding forms, lai-ge and deep black in color, 

 though a little farther apart than in the others. 



Maxillary shield similar to that of the preceding; suture between the 

 two plates running about half way f orward from the posterior end and a 

 little farther than even with the posterior lateral angles. 



Mandibles. — Ventral margin nearly straight; dorsal parallel to it, 

 curving outwardly however toward the posterior end, and this curve con- 

 tinued evenly around the posterior end to the produced posterior ventral 

 angle. Distal joint medium in size and not noteworthy as to form; claw 

 slightly curved, and concave margin slightly arched outwardly in middle. 



Palpi large and heavy, similar to those of the preceding in form. 

 Convex dorsal margin of 2, two and a half times the length of the nearly 

 straight flexor margin and 2 one-third as broad as the length of the whole 

 palpus; there are two spines near the middle of its outer surface, one on 

 the inner near the middle and another near the distal margin which is 

 flat, blade-like and serrate. 3 very broad, its breadth four-fifths that of 

 the preceding and one-half its length; inner margin one-half of outer and 

 both nearly straight. 4 thick, considerably tapering, at the base two- 

 thirds as broad as 2 and at the tip less than one-fourth as broad. Paired 

 papillae three-fourths the distance to the distal end. 5 has the inferior 

 distal angle produced and a spine at the base of the projection on the 

 outer side. 



Epimera occupying two-thirds of the ventral surface, with the spaces 

 between the groups narrow; the inner ends of the anterior groups ap- 

 proach each other much closer than in the preceding, and the posterior 

 margin, instead of being smoothly rounded, shows an excavation oppo- 

 site the junction of the two epimera. Anterior median angles of posterior 

 groups produced, anterior margin concave; the inner margins diverging 

 posteriorly ; the posterior median angles rounded off; and the posterior 

 margin convex, but only moderately so. Suture separating III and IV 

 nearly complete. 



Legs moderately heavy, rather more slender than in the other two 

 species and proportionately shorter, while the species is peculiar in the 

 fact that III is longer than II. In the male I equals about three-fourths 

 the body length, II is somewhat shorter than the body, III about equal 

 to it, while IV, which is shortened, is only one-tenth longer. In the fe- 

 male, all the legs are relatively shorter still and IV is scarcely longer than 

 the body. Length of individual segments in order, beginning with the 

 longest, 4, 5, 6, 2, 3, 1, except in III where 5 is about equal to 4 and in IV 

 of both male and female where 5 is greater than 6 and that than 4. In 

 the female more or less of the spines on the legs are serrate along both 



