OF WASHINGTON. 105 
the beautiful ears of the grass so that I had difficulty in finding perfect 
specimens of the plant. This fact induced me to look a little more care- 
fully into the insects living on Uuiola with the following result: 
A species of Oxacis is extremely abundant on the ears of the plant and 
most injurious thereto. Many ears are entirely denuded by the hundreds 
of specimens found upon a single large plant. They are very active and 
warj', and many specimens fly off on the approach of a person. At this 
season I failed to find the larva in the old roots of the plant, but the same, 
or an allied, species has been bred before by Mr. Hubbard from larvae liv- 
ing in decaying wood buried in the sand along the beach. The particular 
species to which this Oxacis belongs cannot yet be ascertained, owing to 
the confusion into which this genus has fallen by the accumulation of more 
abundant material, which shows' an extraordinary degree of variability in 
coloration and sculpture. 
This Oxacis is vigorously assisted in its destructive work bv numerous 
specimens of Hymenorus densus, the earlier stages of which still remain 
unknown to me. It is true that a large number of larvae are met with 
among the old roots of Uniola as well as other plants growing on the bank 
of the beach, but if the larvae of Hymenorus were among them I have been 
unable to distinguish them from what I took to be the larvae of Blapstinus 
or Phaleria. At any rate, the larvae of Hymenorus and Oxacis live in de- 
caying vegetable matter, and are not injurious to the living plant. 
A third species not infrequently seen on the ears is Mordellistena splen- 
dens. It was observed by me to feed upon the pollen, and of its natural 
history I shall speak further on. 
A fourth abundantly-occurring species is Collops nigriceps, which is seen 
actively running up and down the plant. I could not find out whether it 
feeds on the pollen or on the larva of the insect presently to be mentioned, 
viz : 
The common Chinch Bug (Bltssus leucopterus), which occurs in large 
number on the upper parts of the Uniola, and which, in this southern lati- 
tude, develops some peculiar traits. In regard to geographical distribu- 
tion, it may be of interest to state that the Chinch Bug extends along the 
Atlantic coast as far south as Cape Florida, being absent on the shores of 
Biscayne Bay and on the chain of the Keys, but reappearing on the coast 
of Cuba, and probably also on other islands of the West Indies. The same 
distribution is participated in by Uniola panictilata and many other insects 
and plants. The Chinch Bug further occurs in this southern latitude only 
in the brachypterous form, as I never, among thousands of specimens, saw 
a single macropterous specimen, and it appears that the warm climate of 
semi-tropical Florida, which ought to be rather favorable to the develop- 
ment of the macropterous form, is more than counterbalanced by the tough 
and coarse nature of the food-plant. Uniola paniculata appears to be the 
only food-plant of the Chinch Bug at Lake Worth and Cape Florida, as I 
found only a few scattered imagos on the few other grasses growing on the 
bank of the beach, and on these the bugs may have been blown down 
