24 SANDUSKY FLORA. 



late in the fall it is dangerous sailing in their bark 

 canoes; and in the summer they are so infested with 

 various kinds of serpents, (but chiefly rattlesnakes,) 

 that it is dangerous landing." It is not probable then 

 that the Indians planted anything there, or that any 

 great number of seeds were introduced by them 

 accidentally. 



The difliculty of seeds floating to the islands is two- 

 fold. The prolonged soaking in the absence of definite 

 currents to carry them in that direction is sufficient to 

 destroy the vitality of many kinds. The shores of the 

 islands do not afford conditions suited to the growth 

 of many of the species found in the interior. On Green 

 and Rattlesnake islands there is not a single spot 

 where it seems possible for a plant to start from seeds 

 washed ashore, except such as grow on bare rocks. Six 

 kinds of oak and three of hickory grow on the islands. 

 If all these kinds came from nuts that drifted ashore, 

 one would expect to find somewhere on the shore of 

 some island a tree so situated as to suggest the possi- 

 bility of its having originated in this way, but not a 

 single one has been found. These are long lived trees, 

 and if within the period represented by the growth of a 

 large oak or hickory, there has not been a single in- 

 stance of a nut drifting ashore and finding a suitable 

 place to grow it may well be doubted, if in several 

 thousand years there would be opportunities for all the 

 different kinds to reach so many different islands. The 

 fact that acorns left in the water soon lose their power 

 to germinate increases the difficulty, yet it is not easy 

 to see how, except by floating, acorns or pig-nuts 

 would be likely to reach the islands as long as they 

 were separated from the mainland as far as the3' are 

 now. 



The weeds that have followed civilized man from 

 the Old World, or have spread since the culti- 

 vation of the land from other parts of this, grow on 



