418 Transactions. — Botany. 



The male flowers are of very simple structure, consisting of three sta- 

 mens, without any signs of hypogynous bristles, scales, or other rudiments 

 of a perianth. They are very uniform in all the species, and call for few 

 remarks here. 



The female flowers are composed of a single-celled, one-ovuled ovary, 

 crowned by a short style terminated by two or three long and slender stig- 

 matic branches. The ovary and lower portion of the style are enclosed in a 

 peculiar bottle or flask-shaped organ called the perigynium, swollen in its 

 lower part, but gradually contracted towards the top into a narrow oblique 

 or bidentate mouth, closely surrounding the style. It varies exceedingly in 

 shape and other characteristics, but is tolerably constant in each species, 

 and has thus been largely used for specific circumscription. Inside the 

 perigynium, and between it and the ovary, there often exists a minute 

 bristle-like body called the seta, or rachilla, and usually considered to be a 

 barren pedicel. In the allied genus Uncinia this bristle is invariably pre- 

 sent, is much longer, hooked at the tip, and produced beyond the mouth of 

 the perigynium. 



The perigynium is a structure unknown except in Carex and its imme- 

 diate aUies, and much discussion has arisen as to its nature and probable 

 origin. Three principal views have been advocated. First, that it repre- 

 sents a perianth. Second, that it is to be regarded as of staminal origin. 

 Third, that it is composed of one or perhaps two modified bracts. The 

 first hypothesis was fer long widely accepted, but recent researches have 

 brought to light an almost overwhelming amount of evidence in favour of 

 the last — or that the perigynium is morphologically to be regarded as an 

 altered bract, and the rachilia a rudimentary axis. For a full exposition of 

 the evidence in favour of this, reference should be made to two papers by 

 Dr. McNab and Professor Thistleton Dyer, printed in the Journal of the 

 Linnean Society (Botany, vol. 14, pp. 152-154). 



It follows from the above view of the structure of the female flowers that 

 each perigynium must be looked upon as constituting a one-flowered 

 spikelet. In the inflorescence of C. lucida, for instance, the terminal spike 

 of male flowers would be regarded as a single many-flowered spikelet ; the 

 lower spikes of female flowers as each consisting of numerous one-flowered 

 spikelets. Similarly, an androgynous spikelet, like that of C. pyrenaica, 

 must be regarded as being composed of a single several-flowered male 

 spikelet, and numerous one-flowered female spikelets. 



Fruit. — This is a minute trigonous or lenticular achenium or nut, 

 enclosed in the persistent and hardened perigynium. Its characters are 

 very uniform throughout the species, and are seldom of value for systematic 

 purposes, 



