HENDERSON'S HANDBOOK OF PLANTS. 



321 



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sionally the petals are wanting. The fruit 

 is succulent or dry, one-celled and one- 

 seeded. The seeds are without albumen; 

 the cotyledons of the embryo are rolled 

 up. They are natives of the tropical 

 parts of Asia, Africa, and America. Some 

 of the plants are cultivated for ornament, 

 and others furnish timber. They have 

 astringent qualities, Terminalia Bellerica 

 and T. Chebula yielding the astringent 

 fruit called Myrobalan. The bark of 

 Bucida Buceras is used for tanning. ; 

 There are twenty -three known genera and 

 upward of two hundred species. Com- 

 bretum, Terminalia, and Gyrocarpus illus- 

 trate the order. 



Comb-shaped. The same as pectinate, 

 which see. 



Commelynacece, (bpiderworts.) A natural 

 order of hypogynous Monocotyledons 

 belonging to Lindley's Xyridal Alliance. ! 

 They are herbs with flat leaves, usually 

 sheathing at the base. The outer peri- 

 anth (calyx) consists of three parts, her- j 

 baceous; the inner (corolla) also consists 

 of three, colored; the stamens are six or 

 three, the anthers opening on the side 

 next the pistil. The ovary is three- 

 celled with a central placenta; there is 

 one style. The fruit is a two to three- 

 celled capsule, opening by two or three 

 valves, which bear the partitions on the 

 middle; the seeds have a linear hilum, 

 (which see;) the embryo is pulley-shaped. 

 They are natives of New Holland, the j 

 East and West Indies, and a few are 

 found in North America, but none in 

 Northern Asia or Europe. The under- 

 ground stems of many yield starch and 

 are used for food. The filaments of the 

 Tradescantias have jointed hairs, in which 

 a granular movement is seen under the j 

 microscope. There are sixteen known | 



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genera, and two hundred and sixty 

 species. Commelyna, Tradescantia, and 

 Cyanotis are examples of the order. 



Commissure. The face by which the car- 

 pels come together or cohere, as in Um- 

 bettiferce. 



Common Petiole. The first and principal 

 leaf-stalk in compound leaves; the sec- 

 ondary petioles are called partial 



Compact. Close, hard. 



Complexus. The name for tissue of various 

 kinds; as, Complexiis cellulosus, cellular 

 tissue; C. membranaceus, the thin mem- 

 brane which is the foundation of all tis- 

 sue, elementary membrane; C. tubularis, 

 tubular tissue or woody fiber; C. utricu- 

 laris, angular cellular tissue; C. vascular- 

 is, spiral vessels, properly so called, but 

 often extended to all sorts of tubes with 

 markings on the side, thus losing pre- 

 cision, and with it its value as a scientific 

 term. 



Complicate. Folded up upon itself. 



Complicato-carinate. Folded together so as 

 to form a sort of keel. 



Compositce, (Composites.) The more famil- 

 iar name of Asteracece, a large natural or- 

 der of gamopetalous Calycifloral Dicotyl- 

 edons belonging to Lindley's Campanal 

 Alliance. The order consists of shrubs and 

 herbs with alternate or opposite leaves 

 having no stipules; the stamens and pistils 

 are either in the same or in separate 

 flowers, which are collected into a head 

 on a common receptacle, (hence the name 

 Composite or compound flowers,) and 

 surrounded by a set of floral leaves or 

 bracts called the involucre. The fruit is 

 single seeded, crowned with the limb of 

 the calyx. The plants were included by 

 Linnaeus in his class Syngenesia. They 

 are natives of all parts of the world, and 

 sometimes assume an arborescent form 



