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of view, of such species of Fungi as have been observed to grow in our dwelling 

 houses. We will confine our attention to those which grow on the structure — the 

 walls, floors, ceilings, cellars, &c. — leaving for some future occasion those which 

 attack food and other substances in household use liable to decay. As it is only in 

 later years that attention has been directed to the study of these curious growths, 

 comparatively little is known of their life history, so that for the present we must 

 content ourselves with knowing something of their structure and place of growth 

 only, awaiting the progress of future discovery to reveal to us the deeper secrets of 

 their being. The diflBculties of pushing our investigations further are very many, 

 partly on account of the minuteness of their reproductive organs, and partly on 

 account of the length of time necessary for such investigations. Much, however, 

 has been done in the way of patient observation, both in this country and on the 

 Continent, and the large number of earnest workers will doubtless tend to throw 

 umch light on this interesting subject. 



Our present object is to place before you a list of all the species coming 

 under the designation of our paper, offering a few remarks on some of the 

 more important and interesting ones. The list contains forty-six species, varying 

 very much in their character, arranged in the order in which they are usually 

 placed in English hand-books. 



The first thirteen are not only the first in order, but the first in importance, 

 containing amongst them the species which are the dread of all who are interested 

 in house property, producing the well-known drj'-rot. The one specially credited 

 with this evil is Merulius lacrynians, the Dry-rot Merulius ; but some others, as 

 Polyporus hyhridus, Dry-rot Polyponis, and Polyporus destructor, Destructive 

 Polyporus, sometimes commit similar ravages. It is not always possible to deter- 

 mine the species by which the injury is done, because it does its work in the root- 

 ing stage (mycelial stage) of its growth, while the perfect plant is as yet unde- 

 veloped. The evil effects of these fungi, however, are all popularly designated 

 dry-rot. 



This destructive disease of timber is capable of reducing the largest and 

 smallest beams alike to dry and dusty masses which wll crumble imder the 

 slightest pressure. The whole texture of the wood becomes permeated with the 

 mycelial threads of the fungus, which have the effect of decomposing it and 

 rendering it utterly worthless. It has the power, also, of infecting sound wood in 

 its vicinity, so that it will spread irresistibly throughout the basement storey of a 

 house, or the deck of a ship, rendering the whole fabric unsafe. Much has been 

 said and written about dry-rot, as will be seen by a reference to any of our cyclo- 

 paedias ; and various are the opinions which have been expressed by different 

 writers as to the cause and cure of this disease. It is impossible, however, on this 

 occasion to do more than briefly allude to the subject, leaving its more complete 

 discussion to those who make it a special study. 



Merulius lacrymans, of which we have a striking specimen before us, kindly 

 lent to me by Mr. Jenner, of Easter Duddingston Lodge, Edinburgh, commences 



