40 ENTOMOLOGY 
base of the hypopharynx. In the most generalized insects, 
Thysanura and Collembola, the hypopharynx is a compound 
organ, consisting of a median ventral lobe, or lingua, and two 
dorso-lateral lobes, termed superlingue 
Fic. 48. 
l 
by the author. Superlinguz occur in a 
few other mandibulate orders (Orthop- 
tera, Fig. 48; Ephemerida, Fig. 49), but 
s have not yet been recognized in the more 
specialized orders of insects. 
Suctorial Types.—Owing to their 
greater complexity, suctorial mouth parts 
is rae area - are not nearly so well understood as the 
lingua; s, superlingua— mandibulate organs, but enough has been 
After HANSEN. : 
learned to enable us to homologize the 
two types, even though morphologists still disagree in regard 
to minor details of interpretation. 
The suctorial, or haustellate, orders are Collembola (in 
part), Thysanoptera (in part), Hemiptera, Trichoptera (im- 
perfectly), Lepidoptera, Dip- 
tera, Siphonaptera and Hy- 
menoptera (which have 
Fic. 49. 
\ 
\ MM// f ; 
\ WI U///// \ 
NY UZ Wj \ 
GZ wit ' HO Y WN \ y 
functional mandibles, how- 
vier). 
Hemiptera. — The beak, 
or rostrum, in Hemiptera 
consists (Fig. 50) ot a Hypopharynx of an ephemerid, Hepta- 
conspicuous, one- to four- genia, /, lingua; sl, hs superlingue.— 
our 3 5 After VAYSSIERE. 
jointed labium, which en- 
=> 
sheathes hair-like mandibles and maxilla and is covered 
above at its base by a short labrum. The mandibles and max- 
ill are sharply-pointed, piercing organs and the former fre- 
quently bear retrorse barbs just behind the tip; the two max- 
illa lock together to form a sucking tube. Though primarily 
a sheath, the labium bears at its extremity sensory hairs, which 
are doubtless used to test the food. This general description 
apples to all Hemiptera except the parasitic forms, which pre- 
