January 13, 1870. ] 



JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 



37 



Alcohol operates destructively on these lower forms of vege- 

 tation by depriving them of water. Animal or vegetable sub- 

 stances are, therefore, protected from the effects of fungi by 

 being immersed in alcohol. 



Lastly, there are many ways, which will be described further 

 on, in which these low fungoid forms may be destroyed, and 

 which will in this manner check every process of fermentation 

 and all putridity arising from it. 



Relying on these experiments and investigations, the theory 

 nf foul brood may be briefly stated as follows : — 



Foul brood is the death and putrefaction of sealed and un- 

 sealed brood. We distinguish the infectious from the non- 

 infectious form. 



With non-infectious foul brood the bees die in the larval 

 stage : they remain unsealed and dry up to a grey crust, which 

 is tolerably easy of removal. This kind arises generally from 

 the brood becoming chilled in cold weather, when the bees 

 shrink together and leave the outer comba uncovered. 



Infectious and virulent foul brood first kills the bees when in 

 the nymphoid stage, although, undoubtedly, they are diseased 

 earlier. The sealed ohrysalis changes after a time into a brown 

 paste or yeast like substance. The cell-cover sinks and shows 

 generally a minute perforation. It is probable that this small 

 hole is formed by escaping gases, which break through the 

 cover at this place because it is here last closed, and this is, 

 therefore, the weakest spot. We may readily satisfy ourselves 

 that gases are developed in the cells during the fermentive or 

 putrefactive process by keeping foul-broody combs by us for 

 some time. Taken fresh from the hive the cells appear filled 

 with matter ; after some days we find this either sunk to the 

 bottom or covering only one side of the cells, which appear 

 nearly empty. The foul-broody matter dries at last to a black 

 crust, which rests on the sides of the cells and falls eventually 

 to the ground. 



The Nature of Foul Brood. — Infectious foul brood does not 

 consist of ordinary putrefaction*, but is conditional upon the 

 presence of the smallest fungoid forms in billionfold numbers. 

 These belong to the primary types of fungus, Micrococcus and 

 Cryptococcus, which are related to each other. These fungi 

 increase by division and by gemmation or budding to an im- 



to a single first cause. Let us examine their statements some- 

 what more closely. 



Honey which has become fermented, especially the American 

 and Polish cask-honey, is with one consent named by all writers 

 as the chief cause of foul brood. In the harvesting of all these 

 inferior products it is well known that the brood is not care- 

 fully separated from the honey, and consequently a nitrogenous 

 substance is added to it, additional moisture is speedily imbibed 

 and thus is the fermentation process at once set on foot. Fun- 

 goid elements floating by thousands in the air immediately 

 take the form of Cryptococcus in this mixture ; these begin 

 their increase, and with it fermentation. In this way is Cryp- 

 tococcus carried into the hive. 



It has lately been attempted to bring forward a new theory 

 of foul brood, founded on the proposition that it arises from 

 decomposed pollen, which, being mixed with honey and given 

 as food to the brood, kills it. It has also been stated as a 

 great novelty that pollen contains nitrogen — a fact which has 

 never been doubted. It is plainly enunciated by Dzierzon 

 ("Rational Bee-keeping," page 29), when he says, " The bees 

 also show a desire for food containing nitrogen and albumen, 

 and such for them is pollen." But the fact that decomposed 

 pollen may produce foul brood is also at all events not new. 

 Kalteich says (Berlepsch, " The Bee and Its Culture," second 

 edition, 1809, page 202), " Combs of last year diffused a foul 

 smell ; they were damp, and the pollen was mildewed. I gave 

 these combs to three strong colonies, and all three became foul 

 and perished." 



The fact that decomposed pollen when mixed with honey 

 produces foul brood may, as we shall readily perceive, be traced 

 back to this : that if a nitrogenous substance be mingled with 

 honey and water the conditions of fermentation are fulfilled ; 

 the Cryptococcus, everywhere floating in the air, enters into 

 and multiplies in it, and thus with the fermenting honey enters 

 as food into the hive. Thus it amounts to no greater novelty 

 than this, that fermenting honey produces foul brood.* Who 

 ever doubted that bees and brood could be poisoned by fer- 

 menting and spoilt honey ? 



It has been stated at the ccmmencement that not only the 

 Cryptococcus, but also the allied smaller, and generally the 



measurable extent, and are destructive by their wonderful power smallest fungoid form, the Micrococcus, is met with, and mul 

 of multiplication. They transform the nitrogenous body of the j tiplies in a billionfold manner in foul-broody cells. Most pro 



larva into themselves, consume it, and at last take its place 



The infectious character of the disease rests simply and 

 entirely upon the transmission of these forms of fungus to 

 other hives. 



Whether foul brood is or is not virulent and infectious is 

 proved by inoculating experiments : — 



I extracted foul-broody matter from the cells with a little 

 horn spatula, and put it into a small medicine phial filled with 

 distilled water. After shaking the bottle until the matter was 

 dissolved, I corked it and stood it upside down. In a few days 

 the Micrococcus cells, which are heavier than water, sank to the 

 bottom. I now loosened the cork and let a little of the liquor, 

 which I had examined under the microscope and found to con- 

 tain masses of Micrococcus, flow into a small vessel which had 

 been repeatedly washed with distilled water. I then took from 

 a Dzierzon hive a comb containing young larvas, marked with 

 four pins a space comprising twenty-five cells, and with a fine 

 hair-pencil put into each cell a portion of the liquid containing 

 the fungus. The larva; developed and changed into chrysalids, 

 eighteen of which became foul-broody, whilst in seven the in- 

 oculating matter proved powerless, and healthy bees hatched 

 out. This experiment can easily be repeated. + 



The Micrococcus and Cryptococcus which produce foul brood 

 spring from higher and probably different mildew blights and 

 fungoid organisations, which are not as yet clearly identified. 



The various causes of foul brood which have been stated by 

 different writers, and which are for the most part undoubtedly 

 well-founded, are by these microscopically-proved facts reduced 



* By ordinary putrefaction we understand a whole series of chemical 

 processes, partly of a very complex character, which take place in organic 

 substances. It is always a process of reduction. The elements separate 

 and reunite in fresh combinations, as, for instance, hydrogen and nitro- 

 gen become ammonia, &c. We understand decomposition to be a process 

 of oxidation — the combination of oxygen with the elements already 

 present. Ordinary putrefaction is quite distinct from the specific putre- 

 faction produced by parasites. Specific*putrefaetion exists in milk-fever, 

 and in the mucous membrane of the intestines during cholera. Ordinary 

 putrefaction attacks bodies protected from the oxygen of the air —as for 

 example in the grave— decomposition when they are exposed to the air. 



+ Thoae who see nothing in foul brood beyond ordinary putrefaction, 

 are perfectly unable to explain how the disease spreads from one hive 

 to another. 



bably it is in the form of the contents of the spores of many 

 fungoid and mildew formations that foul-brood fungus enters 

 the hive. 



Whether all or only some of the fungoid and mildew forma- 

 tions are capable of producing foul brood by the contents of 

 their spores has yet to be investigated and established by scien- 

 tific experiments. The culture of the discovered Micrococcus 

 granules in the manner previously described will identify the 

 mother plant. 



The theory that Micrococcus reaches the hive through the 

 contents of fungus spores, explains many remarkable pheno- 

 mena. Holler, of Schroth, 1CG0, page 25, says, "In many 

 years the blossoms of trees are actually poisoned by dew and 

 fog, so that the bees become ill." Hoffmann Brand says in the 

 German Bee Journal, 1856, page 04, "The pollen appears 

 greasy in foul-broody hives, and contains a kind of fermenta- 

 tion, which arises from poisonous dews." Berlepsch says 

 (2nd edition, page 203), " In a conversation which I had with 

 Dzierzon in 1855, he was disponed to assent to the idea of 

 poisonous dews when he said to me, ' I think I have frequently 

 observed this in my own neighbourhood, especially during the 

 time of the tree blossom, and foul brood may'well arise from 

 it ; at least, these poisonous dews are mostly the cause of the 

 so-called vertigo.' " What, then, are these poisonous dews and 

 fogs? Nothing but the fall of fungoid mildew and fever spornles, 

 which, multiplying billionfold, naturally float in the atmosphere. 

 In many years these develope themselves in immense numbers 

 as uni-cells — as, for example, the smut in earn (Uredo segetum) 

 — and in this way every form may readily present itself. 



We may thus perceive that the observations of distinguished 

 naturalists, however inexplicable they may at first appear, are 

 in the end invariably confirmed by science. 



One instance among others, showing that dew and showers 

 precipitate microscopic vegetable atoms to the earth, is afforded 

 by the so-called sulphur rain. Many years ago, I had myself 

 an opportunity of observing this phenomenon, and proved by 

 microscopic examination that the supposed sulphur was nothing 



* The results of the commissio 

 and every significance after this. 



t appointed to test this theory lose all 



