IO THE PINES OF MEXICO. 



PlXUS AYACAIIUITK VAU. VEITCHII N. VAN. 



Pinus Veitchii Roezl, Cat. Grain. Com'/. Mcx. 32 (1857). 



PlNUS B )N.\parte\ Roezl, Gard. Chron. 358 (1858). Gordon, Pinctum. 218 (1858). 



Pint's Loudontaxa Gordon, Pitietum, 230 (1858) 



Differing from the species by the comparatively short and broad seed-wings and larger nuts. 

 Mountains of the central states of Mexico. 



The Washington collections contain no specimen of this variety, but there is in the herbarium of the Arnold 

 Arboretum a cone from the ridge connecting the Volcanos Popocatepetl and Iztacihuatl, collected by Mr. Pringle ; 

 another cone, found on the road between the town of Uruapan and Mt. Tancitaro, was given to me by the late Dr- 

 Altamirano. There are also a few cones in the Arnold Arboretum collection from Pallanza, Italy, where this Pine 

 is cultivated as P. Veitchii Roezl. Cones grown in the Arboretum at Westonbirt, Gloucestershire, England, sent 

 by Dr. Augustine Henry, also have large nuts and broad short wings. In all these specimens the proportion 

 of wing to nut is nearly the same as that in the seeds of P. Lambertiana Dougl. The color of the seed-wing is 

 of no value for determining the varietal forms of P. ayacuhuite. For the wing of Mr. Pringle's cone is dark and 

 opaque, while that of the Westonbirt cones is translucent with dark, opaque striations. The same variation also 

 obtains in southern specimens, the wing of Nelson 3186 being dark and opaque, and that of Nelson 3650 being 

 translucent and striated with dark lines. 



The two cones shown |on Plate V are very different in outline but are alike in the excessive prolongation 

 and revolute form of their apophyses. The Westonbirt cones, on the contrary, bear scales that are somewhat 

 reflexed but not revolute and are considerably thicker. The significance of the cone variations of P. ayacahuite 

 may however become better understood with the accumulation of more material; at present these variations do not 

 appear to be geographical or to be related in any way to variations of the seed or of the leaf. 



P. Bonapartea is evidently, from Gordon's description, the same form as the variety Veitchii. The peculiar 

 characters ascribed to it by Gordon (leaves sometimes in fascicles of more than 5) and by Engelmann (leaves 

 with numerous resin ducts and thick-walled hypoderm) are by no means confined to Roezl's species. My speci- 

 men of the variety brachyptera bears some fascicles of more than 5 leaves, and leaves of any of the forms of P. 

 ayacahuite may contain a strongly developed hypoderm and. numerous resin ducts; indeed it is the occurrence of 

 these and other characters among southern, middle and northern forms alike that makes the separation of the 

 Mexican White Pine into two or more species impossible. 



PLATE V. 



Fig. 1. Cone from Popocatepetl. Fig. 4. Seeds from cone 1. 



" 2. Cone of Dr. Altamirano, 1-3 nat. size. " 5. Sections of leaves, magn. 30 diam. 



" 3. Scale of same, natural size. 



