132 
Psyche 
[December 
surfaces, 0.1-0.21 mm long, mostly bifid (a few with one 
of the branches reduced to a denticle), the branches smooth 
or with a very few denticles. Cranium as broad as long; 
occipital angles smoothly rounded ; occipital border straight. 
Antennae small, each with three sensilla, each of which 
bears a spinule. Head hairs few, long (0.027-0.18 mm), 
flexible and mostly simple (only rarely denticulate). 
Labrum small and very short (breadth three times length) ; 
narrowed dorsally; feebly bilobed due to a shallow medial 
impression of the ventral border; anterior surface of each 
lobe with three or four minute hairs and/or sensilla; ven- 
tral border of each lobe with one isolated and a cluster 
of three sensilla; posterior surface of each lobe with three 
isolated and a cluster of three sensilla; dorsal % of poste- 
rior surface spinulose, the spinules minute and in short 
arcuate rows. Mandibles heavily sclerotized ; somewhat 
short and stout; subtriangular in anterior view; apical 
tooth short; with two teeth on the inner border (one small 
and subapical, the other large and central). Maxillae short 
and lobose; palp a skewed peg bearing five sensilla (two 
apical and bearing a spinule each, two subapical and encap- 
sulated and one lateral with a spinule) ; galea a cone bear- 
ing two apical sensilla. Labium with the anterior surface 
spinulose, the spinules minute and in short rows; palp 
similar to maxillary palp but smaller; an isolated sensillum 
between each palp and the opening of the sericteries; the 
Explanation of Plate 9 
Mesostrumn laevigata Brown, Figs. 1-3. — 1, head in anterior view, 
X95; 2, left mandible in anterior view, X185; 3, larva in side view 
(hairs omitted), X17. 
Alistruma n. sp., Figs. 4-10. — 4, left antenna in lateral view, X740; 
5, head in anterior view, X95; 6, left maxillary palp in lateral view, X740; 
7 and 8, two types of body hairs, X185; 9, left mandible in anterior view, 
X222; 10. mature larva in side view, X30. 
Smithistruma talpa (Weber), Figs. 11-18. — 11, head in anterior vdew, 
X130; 12, anchor-tipped body hair, X370; 13 and 14, denticulate body 
hairs, X370; 15 and 16, bifid body hairs, X370; 17, mature larva in side 
view, X43; 18, left mandible in anterior view, X235. 
Smithistruma nigrescens (Wheeler), Fig. 19, very young larva in side 
view, X43. 
