1935 ] 
Structure of the Pretarsus 
11 
closely associated with the unguitractor which are not act- 
ual processes of it. Eg., the setiform empodium of Asilid 
Diptera is articulated with the unguitractor rather than 
continuous with it ; also the coleopterous empodium in many 
cases gives some evidence that it may be retracted within 
(or beneath?) the unguitractor as pointed out by Hayes and 
Kearns. At any rate the empodium is not necessarily a 
distinct part of the unguitractor, so that the condition in 
Gryllotalpa may be intermediate between the typical iso- 
lated planta (as of Melanoplus) and the empodium of many 
Coleoptera where there is no discernable break between this 
structure and the unguitractor. Ceuthophilus and Gryllus 
may represent a step beyond the Melanoplus type towards 
closer association of planta with unguitractor. 
About all that can be definitely said for the Saltatorial 
Orthoptera (sensu strictu) at the present time is that they 
are linked by a universal absence of basipulvilli and by the 
nature of other more variable features such as planta and 
flexor membranes. In any case there appears to be a wealth 
of material to be investigated within this group. 
Phasmidae — Anisomorpha buprestoides (Stoll) (Fig. 12) 
The absence of basipulvilli would place the Phasmids with 
Saltatorial rather than Cursorial Orthoptera and this is in 
agreement with conclusions presented by students of other 
structures. The unguitractor is narrower than in other 
Orthopteroids, while the planta is more heavily sclerotized 
and is triangular in outline, but is distinct from the ungui- 
tractor, a condition nearer to that of Locustids than to the 
other Saltatorial Orthoptera. The arolium is large and is 
reinforced dorsally by thickened ridges. On the whole the 
condition of the claw segment of this insect may be con- 
sidered as supporting the general conception of the position 
of this family, i. e., related to the Saltatorial Orthoptera but 
developed along its own line of specialization. 
Order Dermaptera 
P satis sp. (Fig. 13) 
Apparently basipulvilli and planta are missing in Psalis. 
If this proves to be true for all Dermaptera, the order will 
