7 o 



ANATOMY OF THE GYMNOSPERMS 



identification without any question, and there was but slight evi- 

 dence of the operation of decay, a fact which goes far to support 

 the hypothesis already discussed, that if the wood is sound when 

 buried in a compact and air-tight matrix, its decay depends 

 essentially upon that which had been initiated before inclosure, 

 and that otherwise there is essentially no change. 



Upon assuming charge of the office of governor of Montreal 

 in 1642, Maisonneuve constructed a palisaded fort near the 

 present location of the customhouse. In 1890, in the course 

 of excavations in that locality, the workmen uncovered hewn 

 timbers which were held to represent a portion of the palisade 

 of the old fort. A specimen of one of these may now be seen 

 in the museum of the Natural History Society of Montreal. It 

 represents the wood of the common red pine (Pinus resinosa). 

 Externally the wood has all the aspects of a recently cut log, a 

 state of preservation which is amply supported by microscopical 

 examination, from which we learn that there is very little myce- 

 lium present, and that the structure is as perfect as if taken 

 from a tree of present growth, notwithstanding its probable 

 burial for two and one-half centuries. 



Data of a more recent character with respect to the duration 

 of timbers used for constructive purposes may be derived from 

 actual experience. Thus Dudley has found that when the yellow 

 pine (Pinus palustris) is employed in the ground or used as ties, 

 it very quickly decays, being destroyed by the action of Len- 

 tinus lepideus, Fr., although the wood is very durable under 

 conditions of comparative dryness (14). In the case of ties from 

 the Panama railway, he also points out that they were useless 

 in two years, while similar ties employed in the southern states 

 lasted from four to six years, and in the middle states they 

 lasted from five to eight years, showing very clearly the influ- 

 ence of varying climatic conditions, particularly with respect to 

 the relative humidity and temperature. According to the same 

 authority, cedar ties (Cupressus thyoides) will last from eight 

 to ten years, even when not wholly sound at the time of laying, 

 while hemlock ties (Tsuga canadensis) have a life of only four 



