210 T. Holm — Studies in the Cyperacece. 



these two forms, the monoecious from the dioecious, as distinct 

 species would not be advisable, inasmuch as we have found no 

 other distinction between these, neither morphological or 

 anatomical, than the varied distribution of the sexes, a char- 

 acter that seems of little import, scarcely even of varietal value, 

 C. gynocrates may be considered as being most frequently 

 dioecious, and among the large number of specimens which we 

 have examined from various parts of this country and from 

 Greenland, there were c. 400 dioecious individuals against 

 76 with androgynous spike. C. monosperma Macoun is among 

 these specimens, and we have failed to find any other distinc- 

 tion between this and C. gynocrates than the smaller number 

 of pistillate flowers, often only one, at the base of the stami- 

 nate spike. If we consider the geographical distribution of 

 C. gynocrates, it seems as if the monoecious form is the most 

 prevalent in the north, judging from the specimens we have 

 examined, which were collected in Northern Labrador, Alaska 

 and Greenland, where we found this species probably at its 

 most northern limit, " Skarvef joeld," on the island Disco, above 

 69° N. lat, where it occurred only as monoecious. 



In regard to C. exilis, this species represents a still more 

 evolute stage, and occurs as dioecious or monoecious, mono- or 

 plio-stachyous. A gynsecandrous spike is frequently met 

 with in this species, besides that the female plant may possess 

 several lateral spikes, from one to six, at the base of the 

 terminal. Car ex Davalliava exhibits a similar variation, pos- 

 sessing androgynous or gynsecandrous spikes besides purely 

 staminate or pistillate, and, moreover, a few pistillate flowers 

 may be found interspersed with staminate in the middle por- 

 tion of the spike. Although the male plant is very abundant 

 in Switzerland, Gaudin* states that the female is exceedingly 

 rare. If we now examine the monoecious forms of C. dioeca 

 and C. parallela, we find these as being much rarer than in 

 the species mentioned above. Carex dioeca L. var. isogyna 

 and C. parallela var. androgyna possess only from one to three 

 pistillate flowers at the base of the otherwise staminate spike, 

 but these forms are only known from a very few localities in 

 Northern Europe. We have, thus, in the Dioicce an analo- 

 gous variation represented by all the species, but merely 

 depending upon distribution of sexes, while in C. exilis the 

 variation extends still further, the monostachyous inflorescence 

 passing over into a pliostachyous. The characterization for- 

 merly applied to these species " spica simplicissima androgyna 

 sive dioica " is actually applicable to each of these, besides that 

 one possesses occasionally a " spica composita " (C. exilis). 



*Gaudin, I., Flora Helvetica, vol. vi, 18.30. p. 21. 



