312 Lake Maxinkuckee, Physical and Biological Survey 



parsnip, Riccia, and other forms found growing in places where 

 it is dry ground part of the year and a good depth of water other 

 times, this plant is remarkable for its protean changes of form, 

 and exhibits the remarkable adaptability of organisms to changed 

 conditions. In winter and spring the leaves, covered with water, 

 are finely dissected, and with the exception of a few choice forms 

 like the water parsnip and some of the Potamogetons, which have 

 exceptional beauty of form, few plants show up so beautifully 

 through the clear ice of early winter. There are few richer ex- 

 periences than walking over the clear ice of some shallow pond, 

 when all the world outside is sere and barren, and looking down at 

 the green velvety water-meadows of water-crowfoot beneath. 



In summer, when the pond is a dry cracked mud-flat, the crow- 

 foots still .persist bright green as ever, but so changed in form as 

 to be hardly recognizable; instead of the leaves being flaccid and 

 finely dissected, they are firm of texture and merely lobed. 



In spring, after the ice has disappeared, and the plant puts 

 forth its new growth, bearing floating leaves and flecking the sur- 

 face of the pond with golden blossoms, we have a vertical variation, 

 the lowermost leaves being finely fimbriate and flaccid, the success- 

 ively higher ones less fimbriate, and the floating leaves like those 

 of the land plant, merely lobed, and rather firm. 



346. PURSH'S BUTTERCUP 



RANUNCULUS PURSHII Richards 



Noted in flower at the tamarack west of the lake May 23, 1901. 



347. KIDNEY-LEAVED CROWFOOT 



RANUNCULUS ABORTIVUS L. 



One of our common, homely weeds found scattered in moist 

 open places, and preferring a heavy clay soil. Quite variable in 

 size and form, with inconspicuous flowers. Found in flower east 

 of the lake May 3, 1901. 



348. HOOKED CROWFOOT 



RANUNCULUS RECURVATUS Poir. 



Common in the woods between Farrar's and Overmyer's near 

 the edge of the pond which joins the lake. Collected in blossom 

 May 20, 1901. The globose heads with their hooked beaks remind 

 one somewhat of the fruits of species of Geum of the Rosacese. 



