December 16, 1869. j 



JOUENAL OF HORTICULTUEE AND COTTAGK GABDENBB. 



495 



naked eye as Boon aa it is dissected ont and placed on a glass 

 slide. The smallest instrument which is serviceable for the ob- 

 servation of foul-brood fungus is the medium-sized microscope, 

 manufactured by Schieok, which has a magnifying power of 

 150 diameters'. Excellent instruments are also supplied by 

 Merz, Zeis, Hartnach, and others, in Munich. 



It has already been stated that the Cryptococcus is round, 

 and that it has a diameter of 0002 milUmttre (l-1095th of a 

 line;. After these observations had been published, I found 

 during the autumn of last year that many foul-broody cells 

 contained also numerous much more minute bodies, which, 

 under the many-thousandfold magnifying power at which Cryp- 

 tococcus appears of a globular form, assumed the same shape, 

 and were identical in character, t Their diameter may be 

 stated at OOi millimetre (1-5500 of a line). It is this form 

 that Hallier has denominated the Micrococcus, seed-cell, or 

 seed-leaven. I have sent pieces of foul-broody comb to Dr. 

 Bail, Director of the Dantzic Naturalist's Society, so celebrated 

 as a microscopist, and especially for his scientific works on 

 mycology, and he has satisfied himself of the existence therein 

 of numberless specimens of Micrococcus. These fungoid forms 

 have also been shown by me to the most distinguished bee- 

 keepers in this district — Wannow, of Giitland ; Lohse, of 

 Stiiblau, and others. In the annexed engraving the small 

 bodies a represent Micrococcus, and 6 the Cryptocooons of foul 

 brood. 





3 





ib'.; 



Fig. 1. 



The science of mycology has been brought to great perfection 

 by the careful investigations of Pasteur, Klob, Bail, Hoffman, 

 and others, and especially by the works of Professor Hallier, of 

 Jena. Hallier's " Phenomena of Fermentation ; an Investi- 

 gation into Fermentation, Putrefaction, and Decay," Leipzig, 

 1867 : his " Vegetable Parasites of the Human Body," Leip- 

 zig, 1866 : " The Cholera Contagion : Mycological Investiga- 

 gations, addressed to Physicians and Naturalists," Leipzig, 

 1867: and finally, " Parasitological Researches; referring 

 Measles, Famine-fever, Typhus, Small-pox, Cow-pox, Variola 

 in Sheep, &c., to Vegetable Organisms," Leipzig, 1868— are 

 especially recommended to those who wish to make themselves 

 masters of the subject. 



We sometimes find this formerly unnoticed organism play a 

 friendly and beneficent part in nature, as, for example, when 

 it becomes the medium of fermentation ; but far more often 

 does the minutest form of Micrococcus spread devastation and 

 death among plants, animals, and men. Who, before the 

 invention of the microscope, could have believed that the actual 

 ^owth of mildew — the lowest form of vegetation — could be 

 made visible to him ! The microscope has shown, moreover, 

 that this is the highest degree of development of still lower 

 forms ; that besides the stalks there are spores, which are 

 small bulbs scarcely visible to the naked eye ; and that each 

 spore when greatly magnified presents itself as a capsule, 

 which when it bursts throws off thousands of spornles, which 

 are capable of motion if brought into contact with fluids. These 

 sporules are the Micrococcus, which, therefore, correspond to 

 the seeds of higher organisms. As there are many kinds of 

 mildew and fungus, so also the number of varieties of Micro- 

 coccus is just as great. These are, however, so excessively 

 minute that the eye fails to distinguish one from another, even 

 when assisted by the most powerful microscope ; only by what 

 proceeds from them, and which at last assimilates itself to the 

 parent stock, can the difference be detected. 



The Micrococcus belongs to the uni-oells. With these is 

 reached the boundary line of creation, within which lies the 

 whole secret of what we call vegetable life. We need only 

 recite one great fact, which forms an immeasurable guli be- 

 tween this type and the inorganic: /( is capable of multiiAijinci 

 itself. A cell consists of a cortex and a kernel, which in the 



•F. W. Schieck 4 Son, 14, Hallische Street, Berlin, supply tliis mi- 

 croscope for loa thalers (aboat £15). The largest manufactored, with a 

 magoifying power of 2500 diameters, costs 200 thalers. The smallest 

 pocket microscope, magnifying 200 times, and sufficient for observing 

 Trichin.-e, 10 thalers. 



+ We often find similar but larger ellipsoidal corpuscles with the Cryp- 

 tococcus. These are the organic cells of the larva, which may be seen 

 by the thonsaud if ire crush the effg of the bee and place it under the 

 microscope. 



Micrococcus are in close contact with each other. By means 

 of its peculiar power, which we call vital force, it exercises an 

 attraction upon the surrounding substance, which serves it aa 

 food. Cortex and kernel enlarge, both divide, and thus one cell 

 becomes two, by each of which the same process is repeated. The 

 Micrococcus can now either increase ad infinitum by dividing 

 itself in two in this manner without assuming a higher type, and 

 remaining unchanged for years may spread itself over vast tracts 

 of country (upon which subject we shall have more to say 

 farther on), or it may develope into higher forms. 



The next higher form of development is this : That the Mi- 

 crococcus forms a hollow space (vacuole) between the kernel and 

 cortex, and that the minute dot-like body changes into a little 

 bulb, in which we can perceive a kernel. This form represents 

 Cryptococcus {fig. 1, li). It multiplies itself, precisely like the 

 Micrococcus, by division. It forms on one part of the cell a 

 bud-like elevation, wliich rapidly increases, and ultimately 

 separates itself and forms a new cell ijig. 1, c), after which the 

 same process is continued. 



Both Miciocoocus and Cryptococcus are comprehended under 

 the name of fermentive fungus. 



The two kinds of increase which have been mentioned take 

 place without the admission of air. Their essential requisites 

 are a temperature between the boiling and the freezing points, 

 moisture, and nitrogen. The development of Cryptococcus 

 flourishes under fewer conditions than that of Micrococcus, it 

 only it be surrounded by strong nitrogenous elements. 



We now come to a still farther development of the lower 

 fungoid forms. 



In Micrococcus and Cryptococcus the cells multiply with 

 extreme rapidity. Under certain conditions, especially with 

 but slight access of air, such as occurs under the bark of trees 

 and beneath the scarf-skin of animals, the cells remain hanging 

 together, and we obtain the form which we call Oidium, and 

 which we see beginning to show itself at c, fig. 2, and com- 

 pletely formed in fig. 3. 





Fig. 2. 



O-O-OO-O-o 



Fig. 3. 



Fig. 6. 



Fig. 4. 



With free access of air we at last witness the formation of 

 the perfect mildew (fig. 4) ; rapid development is already going 

 on at the ends of the cells, where little spores, shells whose 

 contents are innumerable granules of Micrococcus, form them- 

 selves {fig. 5). Thus each fungus runs through four principal 

 stages — Micrococcus, Cryptococcus, Oidium, and Mildew.* 



• I porposely omit the intermediate stages, such as Arthrococcns, Tornla 

 Eormisciam, Leptotrix, &c., which occur during acetous lermectatiou, 



