186 THE PLANT WORLD 



loose sand on north exposures, not attaclied to rocks. It is very abun- 

 dant here but always sterile. Being a reduced form of a rather vari- 

 able species, considerable care has been taken to determine its exact 

 relationship (see The Bri/ologisf, July, 1901). It appears that this par- 

 ticular form occurs also in England and in the Canadian Rocky Moun- 

 tains, 



4. Grimmia feretmervis occurs abundantly near Winona in the same 

 dry situations as do the Coscinodons. It is not known elsewhere in 

 Noi-th America, and we have to go to the alpine regions of southern 

 Europe before we find it again — to Tirol, Kiirnthen, Steiermark. From 

 both regions it is known only sterile. 



5. Webera proligera occurs abundantly but always sterile at several 

 stations within twenty miles of Winona. It was recently found also in 

 Massachusetts, but is at the present writing not known from any other 

 stations in North America.* In Europe it is found in the alpine regions, 

 ranging through Steiermark, Karnthen and Tirol. It also occurs in 

 England and Norway, where it occasionally fruits. 



6. Weisia rP^/w?wer?V«?ft may also be cited here. It was first found near 

 Taylor's Falls, Minn., in the valley of the St. Croix river, and was recog- 

 nized as this species by my friend M. Jules Cardot. Plants since col- 

 lected near the mouth of the Minnesota river, near the Lamoille cave, 

 fifteen miles below Winona, and in the valley of Ti-empealeau river in 

 Wisconsin, are identical with the Taylor's Falls plant. In Europe this 

 plant is considered rare; according to Limpricht (see Laubmoose I: 258), 

 a true alpine moss, it occurs from the Pyrenees through the Alps to 

 Steiermark, "descending rarely below 3300 feet," and yet none of the 

 American stations so far established for it are over 900 feet above sea 



level! 



We have thus seven plants, occurring from one thousand to five 

 thousand miles or more apart from their natural range, in a limited 

 area in the upper Mississippi basin, at an elevation of 2500 to 5000 feet 

 less than these same plants require in their wider range. Four of these 

 have come from the Rocky mountains, the remaining three from Eu- 

 rope. And it is a matter of especial interest, under the circumstances, 

 that while the latter have a considerable alpine range, they were all 

 three collected by one and the same European student, Mr. John Breid- 

 ler, in Steiermark, as is attested by the citations in Limpricht 's Laub- 

 moose. Of the Coscinodons, it is also to be noted that they occur to- 

 gether, both in the Mississippi valley and in Colorado, in both of which 

 regions they were collected by the writer. Converging to this little 

 spot from the Rockies aud the Alps, they must needs be under some- 

 what of a climatic strain, especially at the lower level at which they ar6 

 *See, however, The Bryologist, \: 62, October, 1901. 



