MUSSEL FAUNA OP MAUMEE EIVEB. 



7 



the edge of the old lake plain or " prairie," near the Indian portage 

 and at no great distance from the Little Wabash, struck the main 

 Wabash below Huntington, Ind., and then followed the latter river 

 down to the Ohio. This canal was fed from the two rivers and 

 opened into them at various points along its course. 



There was thus established a channel of communication which, 

 during its half century of existence, must have resulted in the ex- 

 change of many species of mussels, as well as other portions of the 

 fauna of the two rivers. 



Such a canal furnishes an excellent breeding ground for mussels, 

 as is well shown in the case of the old feeder canal at Fort Wayne 

 (p. 19) and the Miami and Erie Canal still in existence between 

 Defiance and Toledo (p. 34) . 



This artificial opportunity for interchange of species, occurring 

 so recently, must have greatly supplemented the original similarity 

 due to the former identity of the drainage basins. It would also 

 go far toward destroying any local peculiarities that might have 

 developed since the two basins were separated. 



The Maumee Basin is situated in the northeastern part of Indiana 

 and the northwestern part of Ohio, and covers an area of 6,500 

 square miles. There are no large hills in or around it, it being a flat 

 glacial plain, covered with moraines and low ridges. The basin 

 abounds in clay and solid subsoil, so that the river is rather muddy 

 most of the time. The water is also quite hard, furnishing an abun- 

 dance of lime to the mussels for their shells. In the upper part of 

 the river, as far down as Defiance, Ohio, there is considerable sand 

 and gravel bottom, but below Defiance a good deal of the bottom 

 is solid bedrock. As already stated, the Maumee is a very young 

 river in point of geological time, yet, next to the Detroit River, it is 

 the largest tributary of Lake Erie and is one of the largest rivers 

 within the State of Ohio. The Maumee is formed by the junction of 

 the St. Joseph and St. Marys Eivers, just beneath the Columbia 

 Street Bridge in Fort Wayne, and flows northeast to Lake Erie at 

 Toledo, Ohio. From origin to mouth is about 100 miles in a straight 

 line, but as a result of the angular or crescentic form of the glacial 

 moraines which separate the Maumee from the Wabash Basin, the 

 river winds greatly, especially that portion of it above Defiance, and 

 thus adds fully 50 miles to its length. 



As might be expected, the current is not very swift except during 

 high floods, since the river falls but 164 feet in its entire course, or a 

 trifle over a foot a mile, and much of this is accumulated in a series 

 of riffles at Defiance and Grand Rapids. Elsewhere the river is made 

 up of long, sluggish stretches, alternating with short riffles of varying 

 lengths, and it is in the vicinity of the latter that most of the mussels 

 are found. 



