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Transactions of the Society. 



more or less pedicillate, and terminated by the persistent style, 

 which is half as long as the carpel. 



The solitary seed conforms to the interior of the carpel. The 

 embryo is curved. The more or less curved horn would no doubt 

 assist in the dissemination. The plant also, like many other 

 aquatic species, is somewhat brittle. 



The fruit of Ncvias is ellipsoid, erect, and terminated by the 

 slender persistent style. One or more are seated in a cup-like 

 cavity formed by stipular sheaths at the base of the leaves, which 

 are opposite, or verticillate. The seeds conform to the interior of 

 the carpel, and the embryo to the seed. 

 N. marina is almost world-wide. 



The pollen of Phragrostis is so narrow and elongated that it 

 resembles a filament of a Conferva. 



Zostera marina has ribbed seeds ; in Z. nana they are smooth. 

 CYPERACEiE (Sedges). — In the Cyperacese the ovary is simple, 

 1-celled and 1-seeded, the perianth being absent, or represented by 

 bristles, three (or multiples of three) in number. The style is divided 



into two or three stigmas. The fruit is a 

 nut, which is triangular in the species 

 with three styles. 



The order comprises some 3000 species. 

 Britain has nine genera, and rather more 

 than 100 species, of which about half 

 belong to the genus Garex and fifteen to 

 Scirpus. 



In Eriophorum (the Cotton Grass), 

 fig. 30, the bristles reach their maximum. 

 For instance, in E. vaginatum var. poly- 

 ^f.W.-Eriophonim angus- stachyum (the Common Cotton Grass) 

 tifohitm Roth. Nat. size. ■? x 7 



F, fruit ; hb, hypogenous the y are vei 7 numerous, united in bundles 

 bristles. at the base, flattened, narrowed to the 



point, white, with a silky lustre, and often 

 attaining 1-H in. in length. They evidently serve for the dis- 

 semination of the seeds. 



The bristles of Bhynchospora and some other genera may serve 

 to entangle the fruits in the fur of any passing animal. 



In Car ex the fruit is inclosed in a bottle-shaped utricle, or bag, 

 enlarged at the base and surmounted by a more or less elongated 

 neck, open only at the top. 



The utricle is often swollen, as, for instance, in C. panieea, and 

 inflated, which would render the fruits light, and facilitate their 

 dispersal either by wind or water. In some cases, as in C. leporina, 

 they are winged. 



The long beak which occurs in many species, and is often 

 serrulate, would, like the bristles, serve to entangle the fruits in 

 the fur of any passing animal. The utricles are generally smooth, 



