Our readers may not generally be aware that for several years the microscope has been employed in Europe for the purpose of scanning the eggs of the silk moth, with a view to separating the bad ones from the good The result of this has been a decided improvement of the stock wherever the the method has been employed A paper, from the pen of M Comalia, published in the Monthly Microscopical Journal, contains the following extracts, which gives an account of a further extension of the use of the microscope to examination of the moths, thereby enabling the grower to withdraw such as are diseased from the general stock, a process which he claims to be more expeditious and efficient than the assorting of the eggs after they are deposited M Comalia asserts that with a microscopic examination limited to the eggs, we make only a half experiment The method is imperfect, and the success resulting from its employment may be attributed (excepting certain bad processes of culture) to examination for corpuscles in the eggs only, for every healthy egg does not necessarily produce a healthy moth He says : " These facts are evidenced by the fact that eggs attacked in the proportion of 4 per cent if proceeding from one of our families of moths, or 8 or 9 per cent if from one of the Japanese races, give verymediocre results In fact, the corpuscles, which I have often insisted on, are the appreciable characters of the disease ; but the eggs may be attacked by the original disease without having these microscopic features In examing the eggs of a corpuscular female, in which they were disposed in chaplets in the ovaries, all the eggs were not found charged with corpuscles " In order, then, to make a definitive experiment to guarantee the healthiness of the eggs, there is nothing like examining the moths before or after they have deposited their ova, in order that we may reject all those eggs proceeding from tainted parents This mode, the most rational, although the most difficult of execution, which M Pasteur has suggested, and which I believe to be alone capable of regenerating our races of worms, was attempted last year at Milan with complete success " In the month of June, 1868,1 received from Zara, a package of cocoons of the ancient Italian race, cultivated on the Dalmatian coast, not far from the shores of the Adriatic These cocoons, about one kilogramme,contained three chrysalides alivo Some of these chrysalides, which I soon examined, and which were not yet perfect, exhibited no trace of the corpuscles It was then that the idea occurred to me of applying M Pasteur's method to the eggs obtained, from healthy moths grown with every care " My friends, the Marquis Crivelli and M Bellotti, undertook this experiment The moths, when hatched out, had a most deceptive appearance, and, when examined by these gentlemen, were found to be free from corpuscles; here there was a perfectly healthy egg, the product of healthy parents, which gave promise, not only of a large produce in cocoons, but even of a healthy crop of moths and of eggs for the culture of the year 1869 " M Crivelli selected Inverigo, in Brianza, to ' bring up' these eggs, in order to surround them with all the necessary care He divided the eggs into three portions ; one of these parcels was given to a peasant in the village, another was reared in his own garden, and the third was sent to a distant locality " It is necessary to state that the mode of' education' adopted by the Marquis was an, extremely careful one; general hygienic conditions being carefully attended to, and the locality, which had some time ago been used as a hospital for cholera patients, having been fumigated with chloride of lime Within a radius of 500 meters no other silkworms were cultivated Moreover, the locality abounded in mulberry treesthis fact being of importancefor had the leaves been imported from other localities they might have been tainted with corpuscles of diseased caterpillars "The cultivation of the three batches proceeded excellently, as on the estate of Inverigo, where the Marquis raised 210 ounces of eggs, of which no more than two per cent were diseased From these 210 ounces he obtained 10,176 kilos, of cocooons, a mean of 48 kilos, to the ounce The three botches ot eggs from Zara did still better, for they produced a maximum of cocoons equal to 62 kilos, per ounce " As may be imagined, the Marquis set apart for the next year the eggs from the last mentioned quality, and he set to work with ardor, and with great hopes of excellent results, but all his exertions were not followed by equal success " The examination of the chrysalides responded exactly to what might have been predicted ; that is to say, that all three batches were equally healthy The microscopic examination of the moths, however, gave quite a different result Those which had been reared in the village and those in the Marquis' garden were diseased ; but those which had been sent to a distance and which wore brought up in the isolated house were perfectly healthy Not one of these last presented any corpuscles, neither in leaving the cocoon nor in depositing ova, nor in decay, nor after death " Here there is a decisive result ; for the eggs were the same and the education of the three batches was alike, save in certain circumstances, on which it is important to insist The peculiar circumstances relate only to the conditions of contagionto the transport of corpuscles In fact, the healthy moths were those which had been reared under circumstances of isolation, in places previously disinfected, and where the worms had been fed with leaves equally isolated " Here there is what is essential to obtain certain results To the ordinary precautions of' education,' conducted with all possible attention as to temperature, aeration, and abundance of food, it is necessary to add isolation of the chambers by a cordon of at least 500 meters radius, and healthy eggs, deposited by healthy moths, cultivated with particular care in isolated localities, disinfected with chlorine, and having a certain 'precocity,' in order to obtain isolation From the foregoing remarks and general experience, M Comalia draws the following conclusions: " 1 An egg, apparently healthy as to its microscopic features, may proceed from very unhealthy parents " 2 An egg, healthy as to its characters under a microscope, may and does give ordinarily a long produce in cocoons, but it may be incapable of giving healthy eggs "3 The absolute health of an egg proceeding from healthy moths (which present only about 4 or 5 per cent of diseased specimens) is an excellent indication of the capacityof an egg to produce healthy moths, which in their turn shall be capable of producing healthy eggs "4 To assure this resuH, it is necessary to maintain all those hygienic and other conditions before mentioned"