l8o TRANS. ST. LOUIS ACAD. SCIENCE. 



II. P. Massom'ana, Lamb. Parlat., well distinguished I'rom the tree thus 

 named by Siebold & Zuccarini and by Endlicher, which was named by 

 Parlatore P. T/iunbergii {see. note 26). It is similar to the last, but has 

 longer and more slender leaves and is a native of the warmer climate of 

 Southern China, and is not hardy where densijlora and Thunbergii are. 

 Ducts few or many, often with a few strengthening cells, these cells also in 

 the corners, very few under the epidermis, rarely some with the vessels ; 

 male flowers slender, cylindric, 6-8 lines long, in a spike, involucrum of 

 6 or 7 bracts, the outer pair rather shorter than the inner ones. Griffith, 

 No. 4992, from Afghanistan, in Herb. Kew, with 2 ducts on the upper side 

 of the broader leaves, may belong here, which would extend the geogra- 

 phical area of this species. 



12. P. Merkiisii, Jungh. & De Vriese, seems to be closely allied to the 

 last and probably belongs here, or ought perhaps to be considered rather a 

 two-leaved Indica. In the poor specimens at my disposal I could not dis- 

 cover any ducts; the leaves are longer and more slender, the strengthening 

 cells similarly disposed. The involucrum consists of 12 bracts, the outer 

 pair not half as long as the inner ones. 



13. P. Gerardiaiia, WalHch. Anther crests semi-orbicular, laciniate- 

 dentate, seeds nearly i inch long. 



14. P. Halepensis, Mill. Cones with longer or shorter peduncles, lateral 

 and often low down on the axis, generally single, with flat or sometimes 

 somewhat tumid scales. 



15. P. Pyrenaica, Lapeyr. , fide Parlatore, P. Bfutia, Ten., and with 

 other synonyms, not to be confounded with that other P. Pyrenaica which 

 is a form of P. Laricio. This species is so closely allied to the last that it 

 is often considered a variety of it. But the leaves are stouter, the more 

 numerous ducts are surrounded by strengthening cells, which are very- 

 scarce in the leaves of the other; in both, these cells are found near the 

 vessels; the male flowers are twice as large; the outer pair of involu- 

 cral bracts is almost equal to the inner ones; the cones are nearly sessile 

 and thicker, generally several together, and often lateral and terminal on 

 the same tree (see p. 171) ; the densely clustered cones in Tenore's typical 

 specimen in the botanic garden of Naples are the result of disease. 



16. P. leiopkylla, Schiede & Deppe, has often 6 and even 7 leaves ; the 

 ducts are very small and often wanting; the strengthening cells, usually 

 well developed in bundles under the epidermis, are, as well as the ducts, 

 absent in Gregg's No. 821 from Zamora; the sheaths are usually decidu- 

 ous, but scarcely so in Hartweg's No. 441. 



17. P. filifolia, Lindl. In a specimen cultivated in Kew gardens the 

 ducts are sometimes internal. 



18. P. MontezumcB, Lamb., is, if I understand it correctly, a most vari- 

 able species, the largest suit of difterent forms of which is preserved in the 

 Berlin herbarium ; some forms have longer, others shorter leaves, or stouter 

 or more slender ones, 3, 4 or 5 in a bundle; cones long cylindrical or oval 

 or conical ; the scales in the typical form are depressed and regularly rhom- 

 boidal, in other forms they become strongly umbonate. It is quite diflii- 



