CATALOGUE. 259 



what I have seen under that name, is a true Cembra, not to be thrown 

 together with P. pygmcea, as has been done, and distinguished from Cembra 

 itself by the denticulate Strobus-like leaf-tips. 3. JEustrobi, with distinctly 

 winged seeds, leaves sharply serrulate on the edges and generally denticu- 

 late all over the tip, mostly without stomata on the back, and with periph- 

 eral ducts, like the last. Of this subsection we have P. Strobus, monticola, 

 and Lambertiana; Mexico has P. Ayacahuite ; Japan, P. parviflora; the East 

 Indies and Turkey, P. excelsa with P. Pence. 



Pinus monophyllos, Torr. & Frem. Report Expl. Exped. 1842-1844, 

 p. 319, t, 4; Parlat. 1. c. 378. — A small tree, of scraggy growth, with gray 

 bark and stout, mostly single,* terete leaves ' (rarely in pairs, and then 

 semicylindrical and entire on the margins), 1J-2' long, J— \" thick or wide, 

 with a deciduous sheath; involucre of the staminate flowers of about 6 

 scales ; anthers with a short, entire or denticulate knob ; cones subterminal, 

 ovate-subglobose, 2 or 2 J' long and nearly as thick, consisting of few large 

 scales with thick pyramidal apophyses, but without prickles ; oval seeds 

 about £' long, with a wing nearly 1" wide; cotyledons 7-10. 



The oft-described Nut-pine of Fremont's first expeditions, 35 years 

 ago, common from Arizona to Utah and California. This and the follow- 

 ing species furnish an important article of food to the Indians and other 

 natives. That single leaf, before its nature was properly understood, troubled 

 botanists a good deal, so that Endlicher, supposing that the single leaf con- 

 sisted of two agglutinated ones, went so far as to change the name into P. 

 Fremontii. They are really single leaves, and the only instance of such 

 leaves in- the genus (I do not speak of the primary leaves of seedlings or 

 young shoots, but only of the secondary leaves, which grow in bundles on 

 what we must take for reduced branchlets). 



* The fresh leaves of pines, when single, are terete, and when dry, become grooved and ridged ; the 

 leaves which grow in pairs are semiterete, flat on the upper or inner, and convex on the lower or outer 

 side, and only when (on the tree as well as still more in the herbarium) they become dry, they assume that 

 channelled form which we find so often described as characteristic of a species; those leaves that grow 

 in bundles of 3 or 5 are convex on the dorsal and ridged on the upper side; those with 3 are flattish, 

 about half as thick as wide ; those with 5 are triangular and nearly as thick as wide. It is therefore 

 superfluous to minutely describe the form of the leaves, as that is already given when the number 

 within the sheath is stated, nor is it proper to describe the dried and shrivelled condition. The serra- 

 tures, their closeness, the size of the minute teeth or their absence (only in a few Western American 

 species the edges of the leaves are without teeth) are of much greater importance, and to some extent 

 the nature of the tip is also of value. 



