92 
Psyche 
[April 
among themselves, but are mutually congeneric according to 
the characters in use at present. There is considerable variation 
in the width of the prosternum between the coxse, but this seems 
to have no generic value, and is often at least partly due to 
superficial lateral dilation of the sternum over the edge of the 
coxa rather than to a change in the insertion of the latter. In 
Helmis simplex, here described, which has a very broad proster- 
nal process, no pubescence is apparent inside the front tibiae, 
and, if the form were not almost exactly that of H. ferruginea 
Horn, the species might be referred elsewhere. The four species 
agree in having eleven- jointed antennae with the second joint 
moderately and regularly enlarged, in having the last joint of the 
maxillary palpus moderately elongate, and in having the last 
ventral segment of all specimens curiously emarginate, the 
emargination having removed a narrow, semi-circular strip from 
the edge of the apex of the segment, leaving the actual apex un- 
changed in form but causing the sides to appear lobed or toothed. 
This character is variable from species to species, but the dif- 
ficulty of describing it has rendered its use inadvisable at present. 
An attempt has been made to select only the more useful charac- 
ters for mention in the descriptions, and to avoid the repetition 
of statements which have been made in the discussion. 
For comparative purposes the key which precedes the des- 
criptive portion of the paper has been constructed to include 
Helmis smithi Grouvelle, which I know only from the literature, 
and the two Texas species H. ccesa Lee. and H. ferruginea Horn, 
of which I have seen the type and authentic specimens, res- 
pectively, in the Museum of Comparative Zoology. I must 
express my thanks to Mr. Banks and the authorities of the 
museum for permitting me to examine these and many other 
specimens, and I must also thank Dr. Thomas Barbour and Dr. 
W. M. Wheeler for arranging my Cuban trip, and Mr. R. M. 
Grey and other friends at Soledad for helping to make my stay 
profitable and enjoyable. 
Key : Cuban and related species. 
1. Pronotum with a pair of sublateral, elevated carinse 
paralleling the lateral margins; palpi pale; intercoxal portion of 
prosternum about half as wide as that of mesosternum 2 
