Holm, The genus Carex in North-West America. I5 



of the grex in North America, we might presume that this con- 

 tinent, and quite cspccially the northwestern corner, constitutes a 

 very nnportant center as to the development and distribution of 

 the Brachystachyae. 



Carices neurochlaenae. 



C. nardina from our region dilTers often from the typical plant 

 by its more slender cuhn and spike, but it is mostly distigmatic • 

 it will be remembered that the plant which we found in Colorado 

 was tnstigmatic, besides a number of examples received from the 

 headwaters of Fräser River in British Columbia. C. glareosa is 

 quite variable, but we have not been able to detect any forms 

 distmct from the European. In C. lagopina, on the other hand, 

 the spikes of the northwestern plant shows a tendency to become 

 more slender and of a lighter color. The very robust C. Prihi/- 

 lovensw is a type of our region, but has not so far been properly 

 described; the spikes are ovoid, densely crowded, and the peri- 

 gynium is broadly elliptical to almost globose, many nerved and 

 abruptly pointed into a very short beak, slit on the outer, convex 

 face. In C. lagopina and glareosa the width of the perigynium 

 varies somewhat from oval to elHptic-Ianceolate, but the beak is, 

 as a rule, very distinct and slender. C. cryptantJia, another Alaskan 

 type, IS characteristic by the prominent development of the scales 

 and the very small inflorescence in proportion to the long, very 

 slender culms. A species typical of Yukon is C. neurochlaena with 

 filitorm culms and prominently nerved perigynia. C. norvegica, 

 the most evolute species of the grex, has also been found in Alaska! 

 thus the Neiirochlaenac are well represented in our region, and 

 more so than farther east. 



Carices astrostachyae. 



Among these C. laeviculmis is a very distinct type of our 

 region, and it is not a rare plant ; the other species with the only 

 exception of O. stellulafa are, on the other hand, rather rare. The 

 grex appears to be much better represented nearer the Atlantic 

 coast and in Europe. 



Oarices acanthophorae. 



The grex shows decidedly a prevalent eastern distribution 

 with such types as C. rosea, sparganioides, Muhleubergii etc. being 

 very abundant along the Atlantic coast. However, some other 

 species seem to be characteristic of the western States, of California 

 and Colorado for instance, while again others appear to have deve- 

 loped farther north, but on the Pacific slope only. Types of 

 North-West America are, thus, ('. occidentalis, vagans Sindphaeolepis, 

 besides the variety costata of C. vicaria. Of these the two former 

 are near allies of C. Hookeriana, while C. phaeolepis is closely 

 related to the Californian C. vitrea and chrysoleuca. These western 

 members of the grex are, altogether, very distinct from the eastern, 

 the spikes of the former being either dark brown or whitish, those 

 of the latter mostly light green. 



Ca rices xerochl aen a e. 



Although both C. marcida and Douglasii are quite frequent 

 within our region their very wide distribution towards South and 



