SYNOPSIS OF THE ORDERS. 17 



4- 2. Perianth small, of 6 equal persistent glumaceous segments; flowers 

 perfect; ovary compound. 



121. Juncaeeae (p. 539). Rush-like. Stamens 3 or 6. Capsule 1- or 3- 

 celled, 3-valved. 



- 3. Flowers without chaffy glumes, the perianth none or reduced to bristles 

 or sepal-like scales ; flowers often monoecious or dioecious ; carpels solitary 

 or united. 

 M. Flowers capitate or upon a spike or spadix, with or without a spathe. 



122. Typhaceae (p. 547). Marsh or aquatic plants, with linear leaves, and 

 monoecious flowers without proper perianth, in heads or a naked spike. 



123. Araceae (p. 548). Flowers perfect or monoecious upon the same spadix, 

 rarely dioecious, with 4 or 6 scale-like sepals or none. 



** *-. Flowers very minute, one or few from the margin of a floating disk- 

 like frond. 



124. Lemnaceae (p. 551). Plants very small, green, mostly lenticular or 

 globose. 



^ 4. Perianth of 4 or 6 segments, the inner often petaloid, or none ; carpels 

 solitary or distinct (coherent in Triglochin) ; seeds without albumen ; 

 aquatic or marsh plants, often monoecious or dioecious. 



*25. Alismaceae (p. 553). Perianth of 6 segments, the inner petal-like. 



126. Naiadaceae (p. 557). Perianth-segments herbaceous or none. 



+- 5. Flowers in the axils of chaffy scales or glumes arranged in spikes or 

 spikelets, without evident perianth ; stamens 1 - 3 ; ovary 1-celled, 1-seeded ; 

 seed albuminous. 



128. Cyperaceae (p. 567). Scales single. Perianth none or replaced by 

 bristles. Anthers basifixed. Fruit a triangular or lenticular achene. 

 Stem solid, often triangular, with closed sheaths. 



129. Gramiiieae (p. 623). Glumes in pairs. Perianth Teplaced by minute 

 scales. Anthers versatile. Fruit a caryopsis. Culm usually hollow, 

 terete ; sheaths split to the base. 



SERIES II. CRYPTOGAMOUS OR FLOWERLESS PLANTS; 



destitute of stamens and pistils, in fructification producing spores in- 

 stead of seeds. 



CLASS III. ACROGENOUS PLANTS. 



Cryptogamous plants with a distinct axis (stem and branches), grow- 

 ing from the apex only, and furnished for the most part with distinct 

 leaves (sometimes taking the form of an expanded leaf-like usually pros- 

 trate thallus) ; reproduction by means of antheridia and archegonia, 

 sometimes also by gemmation. 



SUBCLASS I. VASCULAR ACROGENS, OR PTERIDOPHYTES. 



Stems (and foliage when present) containing both woody fibre and ves- 

 sels; antheridia or archegonia, or both, borne on a minute prothallus, 

 which is developed from the spore on germination. 



