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THE AMERICAN NATURALIST [Vol. XLIII 



Trees four and five inches in diameter may be seen on Point Pinos, 

 still retaining every cone they have produced, circling the trunk and 

 limbs from base to apex. Of course the lumber is perforated with 

 holes, the channels formed by the cone-stems on their many years' 

 journey from heart to bark. 



Other species of western American pines whose cones 

 are serotinous to a greater or less degree are P. muricata, 

 P. contorta, P^ contorta var. Murray mm (the lodge pole 

 pine) and P._ chihuahuana. Of P. muricata Lemmon 

 says: 2 "The cones have been known to remain unopened 

 for twenty or thirty years, then to release good seeds," 

 but he says in another place of the cones of the same 

 tree : 3 ' ' They usually open at the time the leaves at the 

 same point fall away from the stems." The Gardener's 

 Chronicle for April 24, 1909, gives a good illustration 

 of this pine showing old unopened cones, and in the 

 same number, Mr. W. J. Bean says: "Some of the trees 

 at Kew bear cones which must have developed more 

 than a quarter of a century ago." 



Of the eastern American pines the only ones to retain 

 their cones unopened after maturity are the jack pine 

 (P. Banksiana) of the north, the Table Mountain pine 

 (P. pungens) of the Alleghanies, the pond pine (P. 

 serotina) of the southern states, and P. clausa of the 

 gulf coast and eastern Florida. In the case of the last 

 species the cones may become imbedded in the wood as 

 in P. attenuata. 4 



That this remarkable habit of cone retention is of use in 

 the struggle for existence, at least under the peculiar 

 conditions that exist in our western country, is be- 

 lieved by a number of observers. The explanation that 

 is usually offered is well expressed by John Muir in 

 "Our National Parks" page 104. Speaking of Pinus 

 attenuata (under the name of P. tuberculata) he says: 



211 Handbook of West American Cone-bearers/' 3d ed. 

 s Erythea, Vol. 2, p. 160, 1894. 



4 In Garden and Forest, Vol. 10, p. 232, Professor C. S. Sargent remarks 

 that cones of P. muricata often become imbedded in the bark, but in a letter 

 to me he says that this "appears to be erroneous." 



