conifers. SILVA OF NORTH AMERICA, 127 



PINUS CLAUSA. 

 Sand Pine. Spruce Pine. 



Leaves in 2-leayed clusters, slender, flexible, dark green, from 2 to 3 \ inches in 

 length. Cones ovoid-conical, often recurved, serotinous, persistent for many years, 

 their scales armed with short stout straight or recurved spines. 



Pinus clausa, Sargent, Forest Trees N. Am. 10th Census Pinus inops, var. clausa, Engelmann, Bot. Gazette, ii. 125 

 U. S. ix. 199 (1884). —Mayr, Wold. Nordam. 116, t. 8, (1877) ; Trans. St. Louis Acad. iv. 183. — Chapman, Fl. 



f . — Sudworth, Garden and Forest, v. 160, f . 24. — Mas- ed. 2, Suppl. 650. — Beissner, Eandb. Nadelh. 216. 



ters, Jour. B. Sort. Soc. xiv. 227. — Hansen, Jour. B. 

 Sort. Soc. xiv. 356 (Pinetum Danicum). 



A tree, on the sandy dunes of the Florida coast usually fifteen or twenty feet tall, with a stem 

 rarely a foot in diameter, generally clothed to the ground with wide-spreading slender branches which 

 form a bushy frequently flat-topped head, or sometimes in more favorable positions rising to the height 

 of seventy or eighty feet, with a trunk two feet in diameter. The bark on the lower part of the trunk 

 is from one third to one half of an inch in thickness, and is deeply divided by narrow fissures into 

 irregularly shaped but generally oblong plates separating on the surface into thin closely appressed 

 bright red-brown scales, and on the upper part and on the branches it is thin, smooth, and ashy gray. 

 The winter branch-buds are oblong-cylindrical and rather abruptly narrowed at the full and rounded 

 apex, rarely more than a quarter of an inch long, and covered by dark chestnut-brown lustrous scales 

 clothed on the margins with pale matted hairs, those of the inner ranks soon becoming reflexed and 

 separating from their bases, which continue for three or four years to mark the branches. These are 

 slender, tough, and flexible, and are glabrous and pale yellow-green when they first appear, and rather 

 bright red-brown during their first winter, becoming light orange-brown during their second year, and 

 then gradually turning ashy gray. The leaves are borne in clusters of two, with sheaths which at first 

 are loose, light chestnut-brown, and from an eighth to nearly a quarter of an inch in length, but before 

 the end of the first season become thick and dark brown, with loose scarious margins, and less than an 

 eighth of an inch long ; they fall with the leaves during their third and fourth years ; the leaves are 

 flexible, serrulate, acute with short callous tips, stomatiferous with from ten to twenty rows of stomata, 

 dark green, from two to two and a half inches long, and generally not more than one thirty-second but 

 occasionally one twenty-fourth of an inch wide ; they contain two fibro-vascular bundles, and usually 

 two resin ducts, one of which is frequently internal, and which are without strengthening cells, although 

 these are occasionally scattered in the epidermal region. 1 The staminate flowers are produced in short 

 crowded spikes, and are cylindrical, about a third of an inch long and an eighth of an inch thick, with 

 dark orange-colored anthers terminating in orbicular nearly entire or denticulate crests, and are 

 surrounded by involucres of ten or eleven bracts. The pistillate flowers are lateral, from subglobose to 

 oblong, with ovate acute scales gradually narrowed into long slender straight slightly spreading tips, 

 and are raised on stout peduncles about a quarter of an inch in length and covered by dark chestnut- 

 brown lustrous bracts scarious on the margins. During their first winter the cones are horizontal on 

 stout peduncles, and are about half an inch long with sharp incurved spines, and when fully grown in 

 the following autumn they are ovoid-conical, often oblique at the base, usually clustered and reflexed, 

 dark green with the exception of the dark red-brown umbos and spines, from two to three and a half 



1 Coulter & Rose, Bot. Gazette, xi. 308. 



