Cheeseman. — Revision of the N.Z. Species of Carex. 417 



plano-convex. This division includes C. acicularis, (which has a nearly 

 terete leaf) 0. viridis, C. buchanani, C. pidchella, C. petriei, C. comans, C. 

 cheesemanii, and C. littoralis. Second, that in which the opposite surfaces 

 are about parallel to one another. In this class the leaf may be quite plane, 

 as in G. pyreuaica, 0. leporina, C. raoulii, etc. ; involute, as in G. colensoi, 

 C. echinata, etc. ; or keeled, as in G. lucida, G. dipsacea, etc. The leaves 

 are usually grooved or striate ; sometimes with a strong vein on either side 

 of the midrib, — e.g., C. ternaria. G.forsteri, etc. ; and the margins and veins 

 are commonly furnished with minute sharp projections, which all point 

 towards the base of the leaf, so that the skin is frequently cut or scratched 

 if it be drawn sharply through the fingers. In breadth the leaves vary from 

 nearly or quite filiform to one-half or three-quarters of an inch. 



Inflorescence. — The flowers, which are invariably unisexual, are arranged 

 in spikelets of various forms and size, according to the species. The spike- 

 lets may be either solitary, as in C. pyrenaica and G. acicularis ; or few in 

 number, varying from 3 to 6, 8, or 10, as in the great majority of the 

 species ; or very numerous and arranged in a compound panicle, as in the 

 varieties of G. paniculata, and to a lesser degree, in C. kaloicles. The indivi- 

 dual spikelets may be either few or many flowered ; erect, spreading, or 

 pendulous ; sessile or stalked ; close together or more or less distant ; and 

 such characters are often useful in the discrimination of the species. As 

 regards the character of the flowers composing them, the spikelets may be 

 androgynous, with the male and female flowers intermixed in the same 

 spikelet, or unisexual, in which case they are placed in different spikelets. 

 This is an important distinction, and has been made use of to divide the 

 genus into two main groups. It is not, however, altogether absolute, as in 

 the androgynous series spikelets composed wholly of female or male flowers 

 can often be found, and one of the New Zealand species, G. viridis, is even 

 occasionally dioecious. Similarly, in the unisexual group the female spike- 

 lets generally have a few male flowers at the base or apex. The male 

 spikelets are far more rarely mixed, but G. raoulii invariably has them 

 partly female, and occasionally this is the case in G. dipsacea and G. 

 forsteri. 



Floivers. — Each spikelet is composed of an indefinite number of floral 

 bracts or glumes, in the axils of which the flowery are situated. The 

 glumes vary in shape, according to the species, from rounded to lanceolate 

 or linear : they usually have a stout midrib, frequently produced into an 

 awn of variable length ; and thin and membranous, often lacerate margins. 

 Those of the male spikelets generally differ slightly in shape from the 

 female ; and those from the lower part of a spikelet seldom exactly match 

 those from the upper portion, 

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