204 E. W. SEXTON. 



filament on alternate joints ; 1st joint long, nearly equalling the 3rd 

 joint of the peduncle in length ; 2nd joint very short ; 3rd joint 

 half as long again as the 2nd ; apical joint tipped with long setae 

 and one ciliated hair. Accessor^/ ftaf/cUitm as long as the 1st and 2nd 

 joints of the primary taken together. 



0ml parts much as in >S'. papyntcea Stebbing. 



Upper Lip (PI. Ill, fig. 1) partly carinate, distal margin truncate, 

 corners rounded and edged with microscopic spinules. 



Loiver Lip, outer lobes large and rounded, covered with fine hairs, with 

 two double-tipped sensory spines on the inner margin of each, near 

 the apex, similar to those described by Stebbing in S.pcqyyracea; inner 

 lobes inflated, covered with fine hairs ; mandibular processes widely 

 divergent, and narrowed distally. 



Mandibles (PL III, figs. 2 and 3). Eight mandible, cutting-plate 

 margin irregularly crenate, produced below into two large teeth, with 

 one small one between them ; accessory plate large, dentate, the three 

 sharp teeth above separated from the two large rounded ones below 

 by a transverse row of three minute sharp denticles, the uppermost 

 tooth with a denticle at its base. In the figure the plates are laid 

 back to show their structure, which, owing to their great curvature, 

 it is impossible to see in the natural position. In the left mandiljle, 

 tlie cutting-piloie margin is crenate, produced below into two large 

 rounded teeth; accessory plate with five rounded teeth, the lowest the 

 largest. There are six spines in the right spine-rou\ two large ones 

 covered with minute tubercles, and four slender flexible ones, feathered 

 on both sides; eight in the left spine-row, three large and five slender; 

 the 1st spine is falciform in both rows. Molar prominent, strongly 

 denticulate, with a feathered seta inset posteriorly, the teeth on the 

 posterior edge of the crown longer and sharper than those on the 

 anterior portion, front edge sinuous. 



Maxilla 1 very like S. papyracea. Outer plate truncate with eleven 

 spines in two rows, seven long spines in one row, and four shorter in 

 the other. In the row of long spines, the two innermost are finely 

 plumose, the next three denticulate with from twelve to sixteen 

 denticles plumose on the outer side near the tip, the two outermost 

 spines with five and three larger denticles respectively. In the other 

 row, the two inner spines are simple, the 3rd carries one large and 

 two small denticles, and the 4th spine is very stout, curved, and 

 simple. The inner plate is fringed with ten plumose setae, the apical 

 two much shorter than the others. The pxdp is considerably longer 

 than the outer plate, with both margins microscopically serrate; 1st 

 joint short, with three setules on the outer margin ; 2nd joint nearly 



