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assume that any atmospheric condition which seriously affects one class of animal life 
shall more or less act on all such life * * * * Able writers have propounded 
theories founded on the direct action of insect life as, under certain circumstances, — 
likely to produce disease. * * * * Jt is quite true that the ova of certain insects 
may exist for years unhatched; that then, from some peculiar cause, they at once 
become living things, propagating with a rapidity almost beyond belief. * * * * 
T have long since arrived at the conclusion, that as the first bricks of the structure of 
all animals, all vegetation—the cells from which all alike commence—are, so far as 
Science has ascertained, not only similar in apparent structure, but can be affected in 
the same way by the same preparation,—that of cochineal used for microscopic investi- 
gation,—we have much of our life in common with all life around us. I do not believe 
there could be an ox-murrain, or pig or sheep disease, extensive sudden destruction of 
any one crop growing on a large scale, mortality or excessive vitality of any class of 
insect life, without some causes at work liable to produce disease in man and beast, 
herb, every creeping and flying thing, directly connected with life on our common soil. 
* * * * Corrupt animal or vegetable matters beget—I choose that term—vib- 
rionic life, insect life, fungoid life; it is more than probable that this class of living 
products, or products ready to become alive, partake of the nature of that from which 
they are bred; it is, to me, quite possible they may require the same atmospheric action 
to give them active life that caused the death of the beast from which they proceed. 
* * * * JT believe the principles which apply to men, with a certain subordination 
to the peculiar difference in some portions of the economy of life of animals, hold 
good. Jam incredulous as to new diseases. When I am shown a man or beast of 
novel construction, I shall expect to hear of new complications in their organism— 
diseases of derangement of functions as new to us as the functions themselves. In 
cholera and in malignant typhus, we have morbid action and disorganization in excess 
—a destructive excess; in a less degree the animal economy shows the same morbid 
tendency under many other complaints.” 
Mr. Clark remarked that this theory, that the diseases affecting different classes of 
animal life were due to the same cause, namely, the atmospheric conditions to which 
those animals were exposed, seemed not improbable; and it would be interesting to 
know whether any unusual amount of death or disease, any absence of life, or rather 
any inferior vitality, in insects had been generally observed during the present season; 
the almost complete disappearance of wasps seemed to be a case in point. 
Mr. J. J. Weir thought the year was remarkable for the abundance of insect life ; 
and even as regarded wasps, he had, both at Tunbridge Wells and in Somersetshire, 
noticed a considerable (though not a large) number. 
Dr. Alexander Wallace said that, as above mentioned, he had lost a number of his 
Ailanthus silk-worms by disease ; it was during a period of three weeks in the wet 
month of August, when many of the larve were observed to delay their last change of 
skin, to become pale, then livid and sanious, and to fall to the ground; this was coin- 
cident with the prevalence of the potato disease. He had planted potatoes between 
the rows of Ailanthus trees and in some other interspaces, and when the disease first 
showed itself, the potato-stems were pulled up and laid in heaps: the caterpillars in 
the vicinity of the decomposing heaps died in greater numbers than those which fed at 
a greater distance; when fine weather returned the mortality among the worms ceased 
entirely. With respect to wasps, there had scarcely been a specimen visible at Col- 
