66 Lake Maxinkuckee, Physical and Biological Survey 



with marl as are those in the Lake Maxinkuckee beds. Typical 

 Lake Maxinkuckee specimens are dwarfed and stained a deep 

 brown, which obscures the rays. Most of them are thickly coated 

 posteriorly with incrustations of marl. It is principally this spe- 

 cies which has associated with it the little water-beetle, Stenelmis 

 undulatus Blatchley. At Long Point, where L. luteolci is the most 

 common mussel, examples of the peculiar Lost Lake form are 

 rather frequent. In comparing sets of shells from the various 

 mussel beds of the lake — Long Point, Farrar's and the Norris Inlet 

 beds — it was noted that the mussels of each bed, as one approached 

 the upper portions of the lake, averaged somewhat smaller. 



As regards food, movements, reproduction, etc., L. luteola does 

 not differ greatly from the other mussels of the lake with the ex- 

 ception that it appears to be considerably the most active species 

 in the lake. A few were observed moving about during the 

 winter of 1900-1901. The deep water individuals rarely move 

 about at all. In the autumn of 1913 the migration of those near 

 shore into deep water was strikingly shown by a series of numer- 

 ous furrows, with a mussel at the deep water end and extending 

 from shore outward near Long Point. 



As with the other mussels of the lake, reproduction is a rather 

 inconspicuous phenomenon, not attended with the marked display 

 common in the larger river examples. Of 252 examples collected 

 at Long Point Oct. 17, 1907, 25 contained glochidia in the gills, 

 some being very full and much distended. One was found gravid 

 May 24, 1901, and on August 22, 1906, some in Lost Lake appeared 

 to be about ready to spawn. 



The young of this species were found rather frequently in the 

 lake, much more frequently, indeed, than any other kind. The 

 smallest examples were obtained while sieving sand for Sphaeriums 

 at Long Point. These young mussels live buried in the fine sand 

 near shore. Specimens up to about a half inch long are very 

 crinkly, being covered with narrow elevated parallel ridges, gen- 

 erally 5 in number, each consisting of 2 open loops placed end to 

 end, the sides of the loops being roughly parallel with the ventral 

 margin of the shell ; the ends where they join form a sharp curve 

 upward toward the umbone. These double loops are followed by 

 a number of broken irregular ridges. The markings just described 

 persist on the umbones of the older shells until eroded away. The 

 half grown shells are beautifully rayed with green on a whitish 

 background. As the shells grow older they become gradually 

 stained a deep uniform brown, obscuring the rays. 



