500 CHARLES A. DAVIS 



Of the two bays on the west side of the lake, one is much 

 narrower than the other, and at the mouths of both, marl points 

 are extending towards each other to a noticeable degree. 



At all points along the shore the slope of the marl is very 

 abrupt from the shallow water to the bottom, always more than 

 45 , and frequently nearly 90 , this steepness being noticable in 

 the small as well as in the parent lakes, while on the east side 

 of the island at the south end of the lake, the wall of marl 

 seemed positively to overhang, although this appearance was 

 probably due to refraction. 



The texture of the deepest part of this marl deposit is appar- 

 ently that of soft putty ; a sounding rod passed through it with 

 comparative ease, and samples brought up have a yellowish or 

 creamy color, which disappears as they dry, leaving the color 

 almost pure white. At the surface the marl is coarser, slightly 

 yellowish, and more compact. Where it lies above the water line 

 it is distinctly made up of granular and irregular angular frag- 

 ments, resembling coarse sand, but the fragments are very brittle, 

 soft, and friable, and may be converted into powder by rubbing 

 between the thumb and fingers. 



On the parts of the shores where apparently the wave action 

 is chiefly exerted, there are small rounded calcareous pebbles, 

 mixed with molluscan shells, drift material, and considerable 

 quantities of stems, branches, and more or less broken fragments 

 of the alga Chara, all parts of which are heavily incrusted with 

 calcareous matter. This Chara material was often piled up in 

 windrows of considerable extent at the high-water mark. 



The marl banks of the lake, from a little below the water's 

 edge down as far as could be seen, were generally thickly cov- 

 ered with growing Chara. At the time of the writer's visit, and 

 wherever a plant of it was examined, it had a heavy coating of 

 limy matter, which was so closely adherent to the plant as to 

 seem a part of it, and because of this covering the plants were 

 inconspicuous and would easily escape notice. 



Little if any other vegetation of any character was growing 

 in the lakes at this season ; indeed, from the steep slope of the 



