Geology and Natural History. 79 



Wigand's experiments cover many kinds of organized matter, 

 and all of them are interpreted by him in the same manner, 

 namely as proving that these organisms which cause and 

 accompany putrefaction, etc., may or mast arise from the trans- 

 formation of protoplasm. According to him we need not postu- 

 late in any case the pre-existence of germs as necessary to putre- 

 faction. The author touches with his hypothesis many points in 

 physiology and pathology. G. l. g. 



5. "Ringed" Trees. — W. L. Goodwin, Queen's University, 

 Kingston, gives in the Canadian Record of Science, for October, 

 1888, the following details regarding a remarkable case of sur- 

 vival of a pine tree after girdling. The case came under his 

 observation in the summer of 1883. The tree is "a common pine 

 tree which had been ringed several years before I saw it, — ju6t 

 how many I cannot say. The tree stands at the edge of the pine 

 woods of Studley, Halifax, Nova Scotia, and is one of two rising 

 from a common trunk which bifurcates immediately above the 

 surface of the soil. The trees are about 22 feet high, and begin 

 to branch freely at about six feet from the ground. The ring is 

 about four feet from the fork and is eight inches broad. The 

 exposed wood is dead and no signs of life appear within half an 

 inch of the surface. That the tree has grown considerably since 

 it was ringed is shown by the following measurements made this 

 summer: 



Circumference below ring, 194 inches. 



Circumference above ring, 26-| inches. 



The diameter of the tree has thus become two inches greater 

 above than it is below the ring. The condition of the bark and 

 cambium layer below the wound shows that the surface of the 

 tree has died for a considerable distance (over six inches). Above 

 the wound the bark and cambium are living and seem to have 

 pushed down over the scar about half an inch. The same pro- 

 cess had been evidently begun below the ring before the death of 

 -the cambium layer. From measurements made five years ago, I 

 should judge that the tree must have been ringed at least ten 

 years before that date, so that the tree has survived its injury 

 probably fifteen years. Unfortunately the notes of the first 

 measurements are not at hand for comparison. At that date the 

 ringed tree seemed almost as thrifty as its companion, but the 

 foliage showed some signs of imperfect nutrition. At present 

 the tree is in much poorer condition ; many of its branches being 

 dead and the foliage scanty on those that are living." 



Cases of survival after the injury by girdling or "ringing," 

 have been noticed by many observers, but this is, on the whole, 

 the most striking that has yet come to our notice in this climate. 

 On the Pacific coast cases of survival of orange and olive trees 

 are not rare, but they are not so difficult to explain as this of a 

 pine. G. l. g. 



6. A Provisional Host — Index of the Fungi of the United 

 States; by W. G. Farlow and A. B. Seymour. Cambridge, 



