362 The Ohio Naturalist. [Vol. Ill, No. 3, 



AN ENUMERATION OF THE PLANTS GROWING 

 ON A BIG ERRATIC BOULDER. 



Kdo Cr.AASSKX. 



The valley of the Rock}- river abounds in erratic boulders, a 

 small numiier 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 jDor- 

 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 moisttire 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 : 



I^ICHENS. LIVERWORTS. 



1. Cladonia ]nxidata (L.) Fr. 7. Lophocolea heterophylla Nees. 



2. LecideaalbocLerulescenslWulf.) •'^- Metz^eria iiiyriopoda Lindb. 



Srhaer X 9 Porella platyphyl'a Liiidb. 



,, . , ,T \ T^ I'-'. Radula coniijlanata Duniort. X 



3. Leptotiiuni treiiielloides (1^.) Fr. ' 



4. Pariiicliu caperata ( Jv. ) Ach. MOSSES. 



5. Parmelia saxatilis (L.) Fr. u. Dicrainim fulvum Hook 



6. Pelti_yera caiiina (L.) Hoffiii. 12. Hedwigia ciliala Ehrli. X 



TowNSHEND 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 Entomolog)-." He outlined the 

 methods, based on superstition, which were formerly used to free 

 a country from insect pe.sts. The losses due to insects are 

 extreiueh' large but probabh' underestimated. He gave then 

 brief descriptions, illustrated by lantern slides, of many of the 

 most destructive insects, and gave accoinits 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. 



