52 The Philippine Journal of Science 1921 
articulation of maxille, twice as wide as at narrowest region ; 
maxillary palpi longer than mandibles. 
Fontanelle circular, aperture directed somewhat posteriorly, 
channel of about same diameter running forward to base of post- 
clypeus. Antennal carine prominent, edged with red, project- 
ing laterally over bases of antennz, ending at each posterolateral 
corner of postclypeus in a little rounded chitinous projection, the 
medial articulation of the mandible; postclypeus short and 
narrow, more than twice as broad as long; anteclypeus very short 
and white; labrum short, tongue-shaped, with roundly pointed 
apex bearing two hairs. Mandibles as in P. flavus but with 
more gradually incurved tip; antennz of 18 or 20 segments, 
much like those of adult. Compound eye distinct, hyaline, 
lying in midlateral line of head just behind and considerably 
below posterior end of antennal carina. Pronotum considerably 
narrower than the head, somewhat arched with a middorsal longi- 
tudinal groove, slightly concave anteriorly, with shortly rounded 
anterolateral corners; sides rounding broadly into the nearly 
straight posterior margin which is very slightly concave in its 
central region; pronotum 1.35 millimeters broad and 0.65 milli- 
meter long. Pronotum broadest near anterior end, mesonotum 
near middle, and metanotum near posterior end; mesonotum 
narrower, shorter, and less heavily chitinized than pronotum. 
Small soldier —Similar to large soldier but smaller and body 
broader and flatter with head carried at an angle to body, broader 
in proportion to length and not converging anteriorly so much 
as in large soldier. 
Measurements of Prorhinotermes luzonensis sp. nov., small soldier. 
mm, 
Body length 6.00 
Head length, with mandibles 2.50 
Head length, without mandibles 1.60 
Head width: 
Maximum 1.45 
Minimum 1.00 
Pronotum width 1.25 
Pronotum length 0.55 
Worker.—Body much like large soldier. Head like adult 
but much less heavily chitinized and eyes much less prominent. 
Head sutures not very distinct and fontanelle much larger and 
roughly triangular; thickened, rounded articulations at lateral 
ends of clypeofrontal suture distinct as in adult and soldier; 
antenne and mandibles same as in adult; eyes hyaline, larger 
than in soldier, and in same relative position. Antenne of 18 
