86 BOTANY. 



with parallel-veined leaves, sometimes spiny. Chiefly found in Europe, Asia, 

 and North America. The plants of this order are not remarkable for their 

 properties. Some are mucilaginous and astringent. Vallisneria spiralis is a 

 dioecious plant, the male flowers of which, at the time of flowering, are said to 

 he detached from the mud of the' water in which they grow, and to float on the 

 surface. At the same time the female flower developes a long, spiral peduncle, 

 by means of which it reaches the surflxce of the water, so as to allow the appli- 

 cation of the pollen. The canvas-back duck (Aythya vallisneria) derives its 

 specific name from feeding on this plant, known in the Chesapeake Bay as the 

 celery grass. 



This order has been divided into tAVO sections : iStratiotecc, with a many- 

 celled ovary, and Vallisneriece, ovary one-celled. Examples : Limnobium, 

 Udora, Vallisneria. 



iSab- Class 3. DictyogencB. 



Leaves reticulated, often articulated with the stem, branches having the 

 usual structure of Endogens, rhizomes or underground stems having the woody 

 matter disposed in a compact circle, or in wedges containing central cellular 

 tissue, and often showing medullary processes. 



Order 37. Trilliace^, the Trillium Family. Flowers usually bisexual. 

 Perianth in six, sometimes eight divisions, colored or herbaceous. Stamens 

 six, eight, or ten ; filaments subulate ; anthers linear, with a prolonged 

 connective. Ovary free, three-, four-, or five-celled ; styles as many, 

 distinct ; ovules 00, anatropal. Fruit succulent, three-, four-, or five-celled. 

 Seeds 00 ; embryo minute, in fleshy albumen. Natives of the temperate 

 parts of Europe, Asia, and America. Some of them are more or less acrid, 

 others are narcotic. The rhizome of Trillium cernuum is used as an 

 emetic. Paris quadrifolia. Herb Paris, is narcotic. There are about ten 

 known genera, and upwards of sixty species. Examples : Trillium, Paris, 

 Medeola. 



Order 38. Smilace.c, the Greenbrier Family. Flowers bisexual or 

 polygamous. Perianth petaloid, six-parted. Stamens six, inserted into the 

 base of the perianth, rarely hypogynous. Ovary free, three-celled ; cells 

 uni- or multi-ovulate ; ovules orthotropal ; styles usually three-cleft ; stigmas 

 three. Fruit globular and succulent. Seeds with fleshy, cartilaginous 

 albumen ; embryo very small ; usually distant from the hilum. Herbs or 

 undershrubs, often climbing, with netted-veined leaves. Natives of the 

 temperate and tropical regions of Asia and America. There are four or 

 five known genera, and upAvards of 120 species. Examples : Smilax, 

 Philesia. 



The Sarsaparilla of commerce is derived from the roots of various species 

 of Smilax, the best article being furnished by S. officinalis, a native of 

 Columbia ; a poor substitute is found in the S. pseudo-china of the United 

 States. The so-called Avild sarsaparilla of the united states belongs to the 

 genus Aralla. The tangled thickets of Greenbriers, so common in this coun- 

 try, are constituted by various species of Smilax. 

 86 



