518 FLORA OF TEXAS. 



TAXODIUM, Kichard. Cypress ; Bald Cypress. 



Floivers monoecious; sterile aments small, in a long 

 drooping spiked panicle; scales peltate; aiither-coW^ 2-5, 

 opening lengthwise ; fertile aments single or by pairs, with 

 the peltate scales 2-ovuled ; cone globular ; scales very thick, 

 angular, slender-stalked, separating at maturity; seeds 

 3-angled, wingless; cotyledons 6-9, linear. — Trees, with 

 distichous deciduous leaves. 



T. DiSTiCHU3r, Rich. Leaves alternate, opposite, or 

 whorled, on very numerous short and slender deciduous 

 branchlets, linear, acute, 2-ranked or imbricated. (Cu- 

 pressus disticba, L.) Ponds and deep swamps. February 

 and March. — A very large tree, with pale smoothish bark, 

 light durable wood, and few fastigiate branches at the sum- 

 mit; leaves 4"-6" long ; co?ies f-1' in diameter. Attached 

 to the roots are hollow conical knobs called cypress-knees. 



THUJA, Tourn. Arbor Vit^. 



Floivers monoecious; aments small, terminal; antlier- 

 cells 4, with a scale-like connective ; carpellary scales im- 

 bricated in four rows, with two erect ovules at the base ; 

 cojie oblong, the few scales imbricated, expanding at ma- 

 turity, persistent; seed winged; cotyledons 2, oblong. — 

 Trees or shrubs, with scale-like imbricated persistent leaves. 



T. occiDEXTALis, L. (Arbor VifcB.) Branches ^at, dis- 

 tichous: leaves ovate, obtuse, with a gland on the back, 

 imbricated in four rows; co?ies oblong, nodding, Avith the 

 outer scales oblong, obtuse ; seeds broadly winged, emar- 

 ginate at each end. Rocky banks on the mountains. — A 

 small or middle-sized tree; cones ^' long. 



125. CYCAS FAMILY. Order, Cycadace^e. 



Trees or shrubs, with simple trunks, increasing by a ter- 

 minal bud, like the Palms, and composed of a large pith, 



