BOTANICAL GAZETTE. 26- 



above I have found j^lenty of the typical form, like those gathered by 

 Rev, Morong "in shallow rapids at Streets Island above Niagara 

 Falls," mentioned in the Botanical Gazette for May, 1880. They 

 grow in the rapids of St. Mary's River. Those found were on the 

 American side, near the head of the rapids. The water is shallow 

 and the bottom thickly covered with pebbles and stones, among which 

 they root. A few were seen above the rapids. 



Potamogeton (undetermined). This plant, mentioned in the Bo- 

 tanical Gazette of May, 1880, as occuring at Ashtabula, Ohio, and 

 thought to be a variety of P. zostemfolius, Schum., was again found 

 the past season at Manistee. As it grew in abundance, opportunity 

 was given to study it in all stages of growth. The plants gathered at 

 Ashtabula were too itw and imperfect to determine with definiteness. 

 It will apparently have to rank as a new species unless identified with 

 some European form. It grows in stagnant water, in the four places 

 where it has yet been seen, in pools or ponds without an outlet. These 

 are common in Michigan, being 'kettle-holes" made in the boulder 

 clay of the drift formation. Sunk many feet beneath the rim of sur- 

 rounding hills, they furnish a fine soil in their slimy bottoms for the 

 growth of aquatic jjlants. 



Broad leaved forms of another Potamogdon, allied to P. pcctinaius^ 

 also occur at Manistee and Frankfort. At the time of finding, 

 in August, the fruit was barely formed, too immature for determina- 

 tion. It must ripen in September or October. Apparently the same 

 species was detected in the St. Mary's River the present year. Mr. 

 Morong thinks it may be P. flabellatiis, BaDington,a species found in 

 Europe. The attention of collectors is called to this, that those who 

 may have an opportunity to gather it later in the year may secure 

 some with ripened fruit. It may be lookcLl for in situations in which 

 P. pcctinatiis grows, though on the whole it seems to prefer more rapid 

 water. In the St. Mary's River the current was so strong as to bow 

 the stems, three or four feet long, into a nearly liorizontal direction. 

 Some were seen growing in the same condition in the Little Manistee. 

 The broader leaves, the stem pinnately rather than dichotomousiy 

 branched, and tlie late fruit, are good external distinctions, between it 

 and P. pectinatus. I have found the fruit of the latter well formed as 

 early as June 20. All forms of P. pedinatus found at Manistee and 

 Ludington had all the fruit ripe and plants decaying. 



It may be added incidentally that the study of these Potamogdons 

 furnished good examples of the principle of "compensation in 

 growth." When the leaves of P. pusillus, var. major, P. paiiciflorus, 

 and of the last mentioned kind were particularly remarkable for 

 breadth, they were cpiite uniformly devoid of fiuit. They seem to 

 have exhausted their forces in the production of leaves. 



Goodyem Menzicsii, Lind. Sparingly found at Frankfort. Other 

 stations are Petoskey and Boyne Falls, Northport and along Grand 

 Traverse Bay, Mackinac. Common at Sault Ste. Marie, on the Cm 

 ada side. Resembles Goodycra piibcsceus, the common torm at all 



