* Dew 
this is a6 seen in profile, or very nearly so, and is even-« little more obvious in. 
the dorse-ventral aspect. The slight elevations at the base of the conical part of 
the head are due to the presence of four, flattish-hemiepherical, submedian papillae, 
4 microns in diameter, whose summits barely penetrate the cuticle. These papillae, 
fron whatever direction they—ere viewed, have much the same expearanse, but appear 
souewhat wider when seen from in front. The nay musculature extends to the region 
of the papillee and is dietinetly and probably rather strongly developed. The head 
is bilaterally eymnetrical and there are two large,/equal lateral lips GF wand sbLE8, 
7 with outer lateral Broerer or "valleye® along the middle of their distal verte: To- 
ward ‘the base theese depressions, or ‘valleys; are wide, appearing to occupy one-third 
| “the width of the head. The pharynx extends backward & distance somewhat less than 
the sidth of the head, ite posterior Limite being indicated by the refractive nature 
of the "roots" of the two mandibles. The pharynx, ie LONE in the specimen under 
examination jand ite appearance when open remains to be seen. The posterior region 
of the mandiblea, as seen in profile when doaed, consists ef ¢: events twontifthe as 
AJA \IVRAA 
aoe 
long ae the entire pharyae, Jying parallel 4o each other and /eccupying a. space about 
equal to one-eighth the diameter of the base of the head. The number of these ele= 
ments lying side by side remains uncertain but there are et least $00, each perhaps 
alent 
duplex. These organs extend forward to that larger portion of the phar; seal capsule 
which surrounds the anterior part of the mandibles. These latter are bluntly pointe 
ed in front (about 1 micron at the apex) and, in the epecimen under examination, 
terminally they do not quite close together. 
PROFILE VIEW. As seen in perfect lateral view, the head is convex-conoid, and 
then toward the end of the two mandibles almost imperceptibly and slightly irregulare- 
ly concave-conoid, in contour. The mandibles are bluntly pointed, end, when seen 
in profile in the closed position, the external contours lie at en angle of sixty 
‘degrees near the terminus for @ distance of 6 microns. As seen in optical section 
the depth of the pharynx ie again ae already stated. The two mandiblee can be seen 
to be losated in a head capeule 20 microns deep,the wall of which is of considerable 

