116 



SILVA OF NORTH AMERICA. 



CONIFERJE. 



more was heard of it until it was found by David Douglas, who collected in the "interior of N. W. 

 America,'* during his second journey to this country in 1832, a meagre specimen from which the first 

 description of this tree was made, although it was not well understood until 1876, when Engelmann 

 was first able to point out its true characters. . 



Abies lasiocarpa was probably introduced into gardens by Dr. C. C. Parry, who found it in 



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Colorado in 1862 and collected its seeds the following year. Little is known of it as a cultivated plant. 

 The Eocky Mountain Balsam probably always grows slowly,* and in western Europe it suffers from 



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early spring frosts.^ It was first raised in the Arnold Arboretum from seeds gathered by Dr. Parry in 

 Colorado in 1873, and although it is perfectly hardy in eastern Massachusetts, the largest of the plants 

 raised from these seeds is now only ten feet high.^ 



The most widely distributed of the Fir-trees of the New World, ranging through thirty degrees of 

 latitude, and from the coast mountains of the north, bathed in almost continuous moisture, to the arid 

 mountains of Colorado and Arizona, Abies lasiocarpa lives on for centuries safe in its thin needle-like 

 head, which offers the least possible resistance to the gales that sweep over it continuously, and in its 

 tough branches, which no weight of snow can crush, rejoicing in its hardiness and vigor and seeming 

 as enduring as the rivers of ice which often flow at its feet. . 



^ The log specimen in the Jesup Collection of Korth American 

 Woods in the American Museum of Natural History, New York, 

 cut in Colorado, is only fifteen and three quarters inches in diame- 

 ter inside the bark and one hundred and thirty-eight years old, the 

 sapwood, which is three quarters of an inch thick, showing twenty- 

 eight layers of annual growth. 



2 At least one plant raised from seeds said to have been collected 



by Roezl somewhere in North America in 1874, and probably in 

 Colorado, was alive in England in 1888. (See Syme, Gard. Chron. 

 ser. 3, iii. 686.) 



8 Among the plants raised in 1873 in the Arnold Arboretum is 

 one only a few inches high, with spreading prostrate stems, which 

 promises to prove an interesting addition to the dwarf conifers 

 that are highly prized by many lovers of curious trees. 



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EXPLANATION OF THE PLATE. 



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Plate DCXI. Abies lasiocarpa. 



A 



1. A branch with staminate flowers, natural size. 



V, - ■ ., - ' 



2. A staminate flower, enlarged. 



3. An anther, front view, enlarged. 



4. An anther, side view, enlarged. 



5. A branch with pistillate flowers, natural size. 



6. A scale of a pistillate flower, upper side, with its ovules and bract. 



7. A bract of a pistillate flower, lower side, enlarged. 



8. A fruiting branch, natural size. 



9. A cone-scale, lower side, with its bract, natural size. 



10. A cone-scale, upper side, with its seeds, natural size. 



11. A cone-scale, lower side, with its bract, natural size (from 



the Blue Mountains of Oregon). 



12. A cone-scale, with its bract, lower side, natural size (from 



the San Francisco Peaks, Arizona). 



13. A cone-scale, upper side, with one seed removed, natural size 



(from the San Francisco Peaks, Arizona). 



14. A seed, natural size. 



15. Vertical section of a seed, enlarged. 



16. An embryo, enlarged. 



17. The end of a lateral branch, natural size. 



18. Cross section of a leaf, magnified fifteen diameters. 



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19. Winter-buds, natural size. 



