290 



translucent cellular plants, destitute of stomata, having no epidermoid al 

 layer, and perishing rapidly upon exposure to air. M. Amici has seen the 

 sap circulate in the transparent joints of Caulinia fragilis, which he states is 

 the unknown plant upon which Corti made obser\'atioiis relating to the same 

 subject. See Amici in Ann. des Sc. 2. 42. Agardh refers to this order both 

 Ceratophyllum and Sparganium. 



Geography. Common in extra-tropical countries, "but also found near 

 the equator. Potamogetons are in every ditch and swamp as far north as 

 Iceland. 



Properties. Very unimportant. The root of Potamogeton natans is 

 said to be eaten in Siberia, and that of Aponogeton distachyum by Hotten- 

 tots. Zostera, or Sea wrack, is a common material for packing, and for 

 stuffing cottagers' cushions. 



Examples. Naias, Zostera, Caulinia, Cymodocea, Thalassia, Ruppia, 

 Zannichellia, Potamogeton. 



CCLTX. JUNCAGINE^. 



JuNCAGiNE^, Rich. Anal. Fr. (1808); Mtm. Mus. 1. .364. (1815); Lindl. Synops. 252. 

 (1829); Dec. and Duhy., 438. (1828). a sect. o/Alismaceae. 



Diagnosis. Caulescent exalbuminous monocotyledons, with a slit 

 embryo, 6 stamens, and dry superior fruit with erect seeds. 

 Anomalies. Lilsea has no perianthium. 



Essential Character — Sepals and petals both herbaceous, rarely absent. Sta- 

 mens 6. Ovaries 3 or 6, superior, cohering^ firmly; ovules 1 or 2, approximated at their 

 base, erect. Fruit dry, 1- or 2-seeded. Seeds erect ; albumen v/antint^ ; embryo havinfj; the 

 same direction as the seed, with a lateral cleft for the emission of the phimule Herba- 

 ceous bog-plants. Leaves ensiform, with parallel veins. Flowers in spikes or racemes, in- 

 conspicuous. 



Affinities. The plumula lying within a cleft on one side of the em- 

 bryo fixes these plants nearer Aroidese than Alismaceae, to which they are 

 sometimes referred, principally on account of their want of albumen ; and 

 the depauperated state of their floral envelopes confirms the relationship. 

 Juncaginete are most nearly allied to Fluviales, which are readily distin- 

 guished by their floating habit and pendulous ovules. The genus Scheuch- 

 zeria is a transition from Juncaginesc to Junceas. 



Geography. Marshy places in most parts of the world may be ex- 

 pected to indicate traces of this order, which is found in Europe, Asia, and 

 North America, the Cape of Good Hope, and equinoctial America. 



Properties. Unknown. Triglochin has a salt taste. 



Examples. Lila;a, Cathanthes, Triglochin, Scheuchzeria. 



