9 



56 Lake Maxinkuckee, Physical and Biological Survey 



unable to compare our lake specimens with the form that would be 

 most interesting in this connection. 



The mussels of Tippecanoe Lake at the head of Tippecanoe 

 River were examined in this connection. Blatchley (Indiana 

 Geological Report for 1900, p. 190) has reported Anodonta 

 grandis as common, and the subspecies footiana as frequent in 

 Tippecanoe Lake. The Anodontas of that lake differ markedly 

 both in the size and shape of the individuals from those of Lake 

 Maxinkuckee. The difference in size can be easily explained by 

 the more favorable conditions in Tippecanoe Lake. This body of 

 water is more fluviatile than Lake Maxinkuckee, being directly con- 

 nected with the Tippecanoe River, which is already a fairly large 

 stream when it leaves the lake, and the mussel beds of the lake 

 and river are continuous. The upper part of Tippecanoe Lake is 

 exceptionally favorable for Anodontas ; the living mussels are large 

 and abundant, and the dead shells almost pave the bottom near 

 shore, several dead shells often being telescoped within each 

 other. Some of the shells reached a size not often surpassed in 

 the neighboring rivers, one example measuring 172.5 mm. long, 

 95 mm. high and 65 mm. in diameter. A few were thickened with 

 a tendency to form half pearls, but most were thin. A number 

 of the shells approached Anodonta corpidenta in general form, 

 and one flattened, rounded shell resembled A. suborbiculata. The 

 Anodontas from other lakes of the Tippecanoe River system, such 

 as Center Lake and Eagle Lake near Warsaw, resembled those of 

 Lake Maxinkuckee, but were generally smaller and shorter. 



The Anodontas of Lake Maxinkuckee were also compared with 

 those of Yellow River a few miles to the north, and with the various 

 lakes of the Kankakee system, including Upper Fish Lake, Lake 

 of the Woods (Marshall Co), Pretty Lake, Twin Lakes, Bass Lake 

 and Cedar Lake. Some of the Yellow River Anodontas were nor- 

 mal, oval shells such as are common in the rivers of northern In- 

 diana; a few were exceptionally thin and exceedingly inflated, re- 

 sembling A. corpidenta. Those of Upper Fish Lake — originally a 

 fluviatile lake containing other fluviatile shells such as Q. undulata 

 — were large shells like those of Tippecanoe Lake. The Anodontas 

 of each of the othf3r lakes differed more or less from those of the 

 others, though all probably had a common origin. The only lake 

 of this group, the Anodontas of which closely resembled those of 

 Lake Maxinkuckee, is Bass Lake, and even here the shells were 

 somewhat different, being smaller and with the epidermis more 

 deeply stained. Even the Anodontas of Lost Lake differ slightly 

 from those of Lake Maxinkuckee, being somewhat more inflated 



