OSTRYA 



Ostrya, Scopoli, FL Carniol. 414 (1760); Bentham et Hooker, Gen. PL iii. 406 (1880); Winkler, 



in Engler, Pfianzenreich, iv. 61, Betulaaa, 24 (1904). 

 Carpinus, Linnaeus, Gen. PI. 292 {ex parte) (1737). 



Small deciduous trees, belonging to the order Betulacese, agreeing with the genus 

 Carpinus in the characters of the branchlets, buds, foHage, and staminate flowers. 

 Pistillate flowers, in dense erect spikes, inserted in pairs on the base of ovate acute 

 leafy scales, each flower enclosed in a sac-like involucre, formed by the union of a 

 bract and two bracteoles, which is open at the apex at the time of flowering, after- 

 wards becoming closed. Calyx dentate, adnate to the two-celled inferior ovary ; 

 style short, divided into two linear subulate stigmatic branches ; ovules solitary in 

 each cell. Fruits : disposed in stalked ovoid strobiles, composed of densely imbri- 

 cated involucres, which are vesicular, closed, flattened, membranous, longitudinally 

 nerved, reticulate, pubescent at the apex, and hirsute at the base with sharp, rigid, 

 stinging hairs. Nutlet, sessile in the involucre, ovoid, compressed, longitudinally 

 ribbed, crowned by the remains of the calyx ; seed solitary, pendulous. 



Four species of Ostrya have been distinguished : Ostrya Knowltoni, Coville, 

 a rare tree in Arizona, not yet introduced, and three species, occurring in North 

 America, Eastern Asia, and Europe and Asia Minor, which are so closely allied 

 that they have been considered by most botanists to be only geographical races of 

 one species. These three species are all in cultivation, and as they can be 

 distinguished (see Key to Carpinus and Ostrya, p. 526), will be treated by us 

 separately. 



OSTRYA CARPINIFOLIA, Hop Hornbeam 



Ostrya carpinifolia, Scopoli, Fl. Carniol. ii. 244 (1772); Willkomni, Forstliche Flora, 368 (1887); 



Mathieu, Flore Forestiire, 403 (1897). 

 Ostrya vulgaris, Willdenow, Sp. PI. iv. 469 (1805); Loudon, Arb. et Frut. Brit. iii. 2015 (1838). 

 Ostrya italica, Spach. Ann. Sc. Nat. %ix. 2, xvi. 246 (1841). 

 Ostrya italica, sub-species carpinifolia, Winkler, Betulacea, 22 (1904). 

 Ostrya Ostrya, Sargent, Silva N. Amer. ix. 32 (1896). 

 Carpinus Ostrya, Linnaeus, Sp. PL 998 (1753). 



A tree attaining 60 feet in height and 10 feet in girth; stem cylindrical, bark 

 greyish, finely fissured, and scaly. Young branchlets with dense appressed 



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