H. M. PARSHLEY 
21 
be inserted; the fioures are jdaced on the plates in positions eor- 
responding to those in whieh the specimens are most conveni- 
ently set for examination with the usual lighting arrangements. 
Finally, I would refer again to the variability in detail whieh 
tliese insects exhibit; in comparing specimens with the figures 
slight discrepancies will often lie noted, hut experience will soon 
obviate any difhculties which may be encountered on this score. 
Family APiADIDAE 
(Superfamily Aradoidea Reuter) 
Insects of flattened form, living under the dead bark of trees. 
Head horizontal; the tylus greatly enlarged to accommodate the 
coiled trophic setae; antenniferous tubercles usually provided 
with an acute lateral process; bucculae forming a rostral groove, 
which is often continued on the sterna; rostrum four-segmented, 
the first segment very short; ocelli absent; antennae four-seg- 
mented, usually longer than the head. Heniiclytra composeil 
of corium, clavus, and membrane; clavus narrowed toward apex, 
seldom extending beyond apex of scutellum; veins of membrane 
few, irregular, variable within th(‘ species, sometimes lacking. 
Pleural suture's of thorax vestigial. Hind coxae rotatory. Tarsi 
two-segmented, always without arolia. 
T.vpe genus . — Aniduft Fabricius. 
Table of Subfamilies 
Head narroweel behind the eyes, eyes projecting strongly; trochanters 
connate with femora; abdominal spiracles jilaced near basal margin of 
each segment (fig. la) Aradinae 
Head wider just behind eyes than immediately in front of them, eyes not 
projecting; trochanters free; spiracles midway between ba.sal and apical 
margins of segments Mezirinae 
Subfamily Aradinae 
(Family Aradidae Reuter) 
Insects of small to moderate size, wdth roughly tubeirulate 
surface; head narrowed liehind eyes; antenniferous ttdiercles pro- 
longetl in a prominent spine, which is often tootlu'd extei'iially; 
TR.\XS. A.\I. EXT. S()('., XLVII. 
