May 3, 1912] 
Dr. R. J. Terry reported on ‘‘A Grove of 
Deformed Trees.’’ 
A grove of four or five hundred small per- 
simmon trees in St. Louis County has suffered 
from the ravages of a beetle which has been iden- 
tified as Oncideres cingulata. Limbs varying in 
diameter from 5 to 15 mm. are girdled and the 
ends fall to the ground. All the trees, old and 
young, have been attacked. The girdling is done 
in the fall, mainly in September and October. 
During this time the larger trees present scores 
of branches bearing dead leaves and the ground 
is strewn with fallen branches often laden with 
fruit. There is no tree in the grove that does not 
present crooked trunk and limbs. The deformities 
in some cases are extreme. Most of the trees are 
as a consequence dwarfed, although able to make 
some advance in growth. Some trees only a meter 
and half tall bore fruit in 1911. 
A few beetles have been observed working. The 
cut was begun on the upper side of the branch and 
was made 3-4 mm. wide and about 3 mm. deep. 
Most of the limbs fall, probably within a few 
days after the girdling. A small proportion re- 
main throughout the following winter. On every 
severed branch, near the distal ends of the twigs, 
one or more small deep excoriations of the bark 
were found. That the beetle makes similar abra- 
sions of the bark of twigs of the honey locust is 
known from observation on Oncideres in captivity. 
Limbs recovered from the ground in winter in 
some cases presented no evidence of the propaga- 
tion of the beetle, whereas in others more or less 
of the wood had been destroyed under the bark 
along one side of the branch extending from the 
distal end proximally. The cavity never quite 
reached the proximal severed end. lLarve which 
are now being studied were discovered in some of 
the tunnels. 
Av the meeting of the Academy of Science of 
St. Louis, held at the Academy building, March 4, 
1912, Dr. Charles A. Todd addressed the academy 
on ‘‘A Problematical Geological Phenomenon in 
Colorado.’’ 
In the Estes Park district of Colorado there is 
a remarkable collection or aggregation of rocks, 
the exact nature of which at present is undeter- 
mined. This geological puzzle is in the form of 
an oblong pit with sides sloping at an angle of 
45° and meeting at the bottom. Its length is 600 
feet; width, 200; depth, 50. These measurements 
are only estimates. At the eastern extremity of 
this oblong is a circular pit 150 feet in diameter. 
SCIENCE 
715 
Both pits have the same general characteristics. 
Their walls are of more or less cubical masses of 
country granite, sharp angled and solidly jammed 
together for the most part. The largest blocks are 
on the upper part of the wall; one I judged to 
be 30 X 40 feet with irregular thickness. These 
pits are in the valley of Fern Lake on a branch 
of the Thompson River and about three miles 
from the Continental Divide. They are on the 
right-hand side of Fern Lake, forming part of the 
shore. All this district has been subject to glacial 
action and this valley gives all indication of having 
been plowed out by the ice. Fern Lake is a cir- 
cular glacial lakelet about one fourth of a mile in 
diameter and said to be 75 feet deep. Its shores 
drop off abruptly with the depths. Just above the 
lake is a bench extending two miles up stream to 
another and larger glacial lake. At the lower end 
of Fern Lake is a terminal moraine, filling the 
valley (which is here about three fourths of a 
mile wide) and extending down stream two miles, 
where the main Thompson flows through a rather 
wide cafon. The question is, how came these rocks 
here and so arranged. Two theories are advanced: 
One is that the pits represent a ‘‘blow-out.’’ In 
that case the applied force must have been gaseous, 
since there is no lava or ash in the neighborhood. 
The second theory is that the rocks are glacial 
deposit. They are, as stated, in the course of the 
ice stream and next an extensive moraine. But 
the peculiar configuration of the pits, the sharp 
angles of the cubical fragments, ete., seem to 
oppose this view. The surest way to settle the 
matter evidently would be to sink a shaft in the 
bottom of the main pit and determine whether or 
not the broken rock extends well below the general 
level of the valley at that point. 
Dr. H. T. A. Hus, of the University of Michigan, 
read a paper on ‘‘ Inheritance in Capsella.’’ 
Professor Nipher made a verbal communication 
concerning some of his more recent work on the 
nature of the electric discharge. Former results 
of his work seem to point very strongly to the one- 
fluid theory. It would follow that the two waves 
which were shown to exist in the Wheatstone ex- 
periment were compression and rarefaction waves. 
The negative wave is in the nature of a super- 
charge which travels along on the outer surface of 
a thin outer film of the conductor. The positive 
wave is one in which a thin outer film of the wave 
is suddenly drained of the negative charge, at the 
instant of passing of the wave. We had been led 
to suspect as a result of recent experiments that 
