34 



always clear, cold and surcharged with lime, and often con- 

 centrated in springs. Many rock mosses form green matted 

 layers covering the rock face, with numerous algie intermixed, 

 particularly Spirogyra species. Marchantia and Lunulria or, 

 less abundantly, Concephalus, are liverwort forms that often 

 clothe great spaces with a solid green covering, and winter 

 or summer are obtainable for purposes of study or collection. 

 A half dozen flowering plants form an association at once 

 interesting and attractive. The most remarkable species is 

 Priniiihi Mistassinica, which forms a thick mat-like growth, cov- 

 ering in one instance a space about three rods long by about six 

 feet of vertical height, on that part of the cliff with the greatest 

 amount of drip. The winter rosettes of this plant are well 

 formed by September 1, and the numerous leaves evidently 

 act as a cold protection for the innermost, immediately sur- 

 rounding the root-crown, and these latter, are doubtless full 

 of elaborated food fit for the immediate use of the plant the 

 following spring, for in average years it is in full bloom by April 

 20, and then often tints the otherwise bare rock a lavender 

 purple with the multitudes of its blossoms. By the end of May 

 its seeds are ripe, and evidently many soon germinate, for tiny 

 plants with but three or four root leaves are common in 

 August. Steironema qnadrifloriim adds a brilliant hue to the 

 green of these same zones, in July and August when nothing but 

 the leaves of the primrose are to be seen. The yellow flowers of 

 this species are produced in great abundance, and as a rule, 

 the plants seem in every way more vigorous than when found 

 growing in the ordinary boggy home of other regions. 

 Dasiphora fruticosus is a very abundant form and extends ver- 

 tically over much more of the cliff face, blooming until cold 

 puts an end to its growth. This plant never assumes on the 

 cliffs the robust habit it has in the tamarack marshes of Michi- 

 gan and Wisconsin. Galium tinctorhim is another very com- 

 mon plant of this association but not at all conspicuous. In the 

 crevices and narrow ledges occasional robust specimens of 

 Cypripedium reginae are to be found. So astonishingly differ- 

 ent is such a hal)itat fnjm the slough margins of Lake county, 



