Nov., 1902 .] 
Passalus Cornulus. 
3°9 
there is a spindle-shaped area where the veins are separate. The 
proximal portion of this vein is connected by a transverse chitin- 
ized bar with the next vein, and from this point is continued as 
a strongly chitinized bar to the end of which the articular mem- 
brane lying in front of the wing is attached. 
The subcosta (14) lies just posterior to the costa and is 
closely fused to it except at the point mentioned above and also 
at the proximal end where after fusing with the transverse bar 
connecting it with the costa it projects toward the median line and 
articulates with a large movable sclerite. The fused costa and 
subcosta can be traced as far as a transverse articulation of the 
outer third of the wing. 
The radius (15) is a large vein lying posterior to the sub- 
costa and extending from the base of the wing to the transverse 
articulation. At its proximal end it is interrupted by an oval 
membranous area over which it extends as a narrow bar, and be- 
yond this enlarges and fuses with the enlarged end of the sub- 
costa. It also sends posteriorly a small process which articulates 
with one of the free sclerites. Distally beyond the tranverse articu- 
lation of the wing these veins are continued as a broad slightly 
chitinized area. Just posterior to this broad area which forms 
the anterior margin of the outer third of the wing is a short vein 
extending from the articulation of the wing. It is the posterior 
division of the radius. 
The next three veins arise together from an irregular plate 
formed by the fused and enlarged ends of the veins. The plate 
articulates with the movable sclerite by a well defined process ex- 
tending between two non-chitinized areas. The media (16) is the 
most anterior and the largest of the three. At its base it is in 
contact on its anterior border with the radius. Distally it separates 
from the radius and at the transverse articulation turns poster- 
iorly and reaches the margin of the wing. There is a second short 
vein lying anterior to the distal end of the medius and reaching 
from the transverse articulation to the tip of the wing. This is 
media No. 1, the main vein beyond the articulation being media 
No. 2. Posterior to the main branch of the media and within 
the transverse articulation is a small vein which is probably media 
No. 3. It does not come quite into contact with the media but 
arises near it. 
The cubitus (17) is the second of this group and arises pos- 
terior to the medius and is in contact with it for some distance 
after which it turns by a gentle curve to the anal margin of the 
wing. It forms a large triangle in which the third division of the 
media lies. 
The third ( 18) and most posterior vein arising from this plate 
is the first division of the anal vein. It is not in contact with the 
