3 62 
The Ohio Naturalist. 
[Vol. Ill, No. 3, 
AN ENUMERATION OF THE PLANTS GROWING 
ON A BIG ERRATIC BOULDER. 
Edo C[.aasskn. 
The valley of the Rock}- river abounds in erratic boulders, a 
small number of which represent the limestone of the Lake Erie 
islands, and the balance the granite, etc., of the Canadian high- 
lands. The largest among the latter is found on the bottom of a 
creek, flowing into a river which empties into Lake Erie. 
The boulder in question is of the granite type, almost spherical 
in shape, and has a diameter of seven feet. While a large por- 
tion of its surface is vertical or too smooth to allow any vegeta- 
tion to grow, there are many places that furnish the necessary 
substratum for the spores or cells of various cryptogams to ger- 
minate and develop. Sufficient moisture during the greater part 
of the year and a shady locality, now and then penetrated by the 
sun’s rays, have, no doubt, exercised no small influence on the 
growth of this boulder flora. 
All plants occuring on the boulder are cryptogams. Besides 
one alga they represent the following species, of which only those 
marked with an X were found in a fruiting condition : 
LICHENS. 
LIVERWORTS. 
I. 
Cladonia pyxidata (L.) Fr. 
7* 
Lophocolea heterophylla Nees. 
2. 
Lecidea albocreruleseens (tVulf.) 
8. 
Metzger ia myriopoda Lindb 
Schaer. X 
9 - 
Porella platyphyl’a Lindb. 
3 - 
Leptogium tremelloides (L.) Fr. 
IO. 
Radula complanata Dumort. X 
4 - 
Parmelia caperata (L.) Ach. 
MOSSES. 
5 - 
Parmelia saxatilis (L.) Fr. 
1 1 . 
Dicranum fulvum Hook 
6. 
Peltigera canina (L.) Hoffm. 
I 2. 
Hedwigia ciliata Ehrli. X 
Towkshend Hall. 
The Club met in Townshend Hall in order to avail itself of the 
lantern. Prof. Osborn gave the address of the evening on “ The 
Achievements of Economic Entomology.” He outlined thy 
methods, based on superstition, which were formerly used to free 
a country from insect pests. The losses due to insects are 
extremely large but probably underestimated. He gave then 
brief descriptions, illustrated by lantern slides, of many of the 
most destructive insects, and gave accounts of methods of dealing 
with them. He then spoke of the beneficial insects, the domesti- 
cated forms, the bee and the silk worm. He concluded by em- 
phasizing the dependence of economic Entomology on other 
sciences. 
Mr. Sweezy was elected to membership. 
Robert F. Griggs, Secretary. 
