68 
Psyche 
[April 
shown in Fig. 8, and the termite shown in Fig. 10, the anal, or 
claval, area aa of the tegmen (fore wing) is connected with the 
notum by a region called the alula, or jugalula ja which may be 
involved in the formation of the jugum etc., of higher insects. 
An axillary ridge, or a crack-like rima po (Figs. 6 to 10), sep- 
arates this region from the anal or claval region aa (Figs. 6, 7, 8, 
9, 10, 16 etc. and the veins which are located behind this line of 
demarcation (i .e. such as those labelled ax in Figs. 8 ; 9, etc.) 
should be referred to as the axillaries or axillary veins. The 
faintly chitinized and pigmented areas labelled ju in Figs. 6, 10 
and 16, are formed in the basal region of the alula; and the 
sclerite behind the metathoracic ossicle ha of Fig. 16, may be 
associated with these areas of the fore wings. The sclerite pju 
of the hind wing of the roach (Fig. 16), however, seems to be 
formed behind the area containing the region ju in the fore wing 
(Fig r 16), and is connected with a different portion of the notum 
by a narrow neck as is shown in Fig. 16. The relation of these 
parts to the calypteres of Diptera, etc., will be discussed in 
another paper. 
In studying the fore wing of the roach I noticed a basal, 
ridge-like fold hp and a deep “marsupium” or basal sinus hsi 
(best seen after boiling the parts in caustic potash to spread 
them apart more readily), such as that shown in the tegmen 
(modified fore wing) figured in Fig. 16 These structions are 
very prominent, but have been apparently overlooked before, 
although they occur in a great many of the insects descended 
from the ancestral types included in the common Protorthop 
teron-Protoblattid stem — e. g. in such insects as those shown in 
Figs. 11, 16, 7, 8, 9, and 10. I do not find this basal fold and 
sinus in such insects as the ephemerids and Odonata which 
cannot lay their wings back along the top of the abdomen in 
repose, while the descendants of the groups which can do this 
(see division of insects into two groups on this basis in Yol. 16 
p. 33 of the Journal of Ent. and Zoology for 1924, or papers in 
the Transactions of the Amer. Ent. Society, ,LII, 1926, p. 239) 
show distinct traces of the fold and sinus (as I have also pointed 
out in the Bull. Brooklyn Ent. Soc., 1927, XXII, p. 1) so that 
the presence of these structures is of considerable importance 
