192 KAARE MÜNSTER STRØM. 



our country suitable localities may be found as perhaps in no other 

 country in Europe, except the British Islands There is always 

 an abundance of bogs, both Sphagnum-bogs and others, and 

 smaller or larger pools, tarns and lakes. In addition to this, only 

 about 4 % of the surface is cultivated, the other 96 % being 

 almost virgin districts, with more variation in geology, 

 climate and other factors with influence onlhealga- 

 flora, than any other country in Europe, perhaps 

 in the world. — Here is a wide field for future algologists, 

 and many of the problems of algal ecology, biology and geo- 

 graphy can be easier worked out here than in any other part 

 of the world. 



At Tuddal there was a distinct absence of a few common 

 species; such as: Euastrum oblongum, almost all the large 

 Closterice, and other desmids. Cosmarium Botrytis, which is 

 so common in the lowlands, was very scarce. — The frequence 

 of each species is to be seen at the association-lists. 



About the geographic affinities of the desmid-flora is more 

 to be said. — Many of the desmids observed were of distinct 

 western types, a few arctic or alpine, — Of the western types 

 are to be especially mentioned: Tetmemorus Brebissonii var. 

 minor, which was general and sometimes in considerable quan- 

 tities, Micrasterias conferta, Euastrum intermedium, Docidium 

 undulatum, Cosmarium quadrifarium, which was quite general, 

 G. tumidum, Staurastrum Ophiura, which was not un frequent, 

 St. megalonothum, St. jaculiferum. — Many others, which are 

 only frequent in the rich districts in western Europe, occurred, 

 such as: Netrium oblongum var. cylindricum, which was quite 

 common, Penium exiguum, Closterium Ulna, Tetmemorus 

 minutus, Euastrum crispulum,, E. inerme, E. pinnatum, which 

 was frequent, E. sublobatum, Cosmarium connatum, C. Ham- 

 meri, C. pseudopyramidatum, which was one of the most 

 frequent desmids, C. subundulatum, Staurastrum sçabrum, 

 St. aristiferum. 



