280 



THE AMERICAN BEE JOURNAL. 



from the dried-up matter escape, and are 

 borne away by the atmosphere. 



Therefore there cannot be the slightest 

 doubt of the fact, that in consequence of 

 the bees ventilating so strongly as they so 

 often do, that the spores must be driven out 

 of a severely infected hive in very large 

 quantities. 



When V. Molitor-Muhlfeldt, in order to 

 refute this assumption, declares that there 

 is no circulation of air in a bee-hive, but 

 that, owing to the motionless air, the spores 

 must sink down, and not pass from cell to 

 cell, it sounds almost as if lie had no idea of 

 ventilation being caused by the bees, and as 

 if he had not read paragraph 3 of Von Ber- 

 lepsch's Der Biene. When Gunther has 

 succeeded in working a small windmill of 

 paper by placing it at the entrance of a hive 

 containing a strong stock, then it is evident 

 that the circulation of air produced in the 

 hive by the bees must, in proportion, be 

 a much stronger hurricane for these light 

 spores than any such hurricane Von Moli- 

 tor-Muhlfeldt has witnessed on the earth. 

 And when the same opponent declares on 

 the whole that the atmosphere cannot be 

 the bearer of the infection, so has that in- 

 valid assertion been so thoroughly refuted 

 by Dr. Ulde, of Halle, that I will not waste 

 a word on the subject. 



It is quite certain that it is not over all, 

 and at all times, that the atmosphere will 

 contain such a quantity of seed-germs; and 

 Dr. Preusz goes too far when he declares 

 that the atmosphere is everywhere loaded 

 with these germs. If such was the case, 

 foul brood infection would appear in every 

 district where there are bee-keepers; but 

 there can be shown many districts where 

 this disease is quite unknown; as in my 

 district, up to the present time, it has not 

 appeared. 



1 certainly succeeded in producing a 

 whole comb of dead rotten and stinking 

 brood; but although I experimented with 

 this comb in the most various ways, placed 

 it at the fly-hole at the open door, and ex- 

 posed to the sun's warmth and the atmos- 

 pheric currents about my pavilion, I, after 

 examination, found no more fungus than 

 Fischer, who never had anything to do with 

 foul brood. 



Where there is no fungus present, there 

 can never arise infectious foul brood. 



Herewith we have approached nearer to 

 the solution of the second part of my pro- 

 blem. 



It next requires to show and afterwards 

 to prove that pure fungus collected from 

 the atmosphere by means of cotton wool, 

 has the power to kill larvie, and by so doing 

 cause foul brood. To do this, I took, on the 

 30tli of July, a comb with brood from a first 

 swarm, brushed off all the bees, and cover- 

 ed about 100 larvae with wool, which was 

 made fast by means of some thread. The 

 comb was hardly replaced again before the 

 bees attacked the wool, and comnienced 

 casting it out in small pieces. On examin- 

 ation of the comb on the 1st of August, it 

 showed that all the larvae that had been 

 covered with tin; wool were cleared away 

 by the bees. Three larviB above the pre- 

 viously closed cells died shorty after the 

 bees had sealed the cells which they were 

 in. The bell-covers were sunk, and the 

 well known small hole was in the centre. 



After this, about 100 other larvae were 

 covered with wool; but again, as also a 



third time, the larvse and wool were torn 

 out. I had nearly lost my patience, and I 

 had only now two plugs and one of the 

 squares left, which should be used for other 

 experiments. 



I now, rather anxiously, for a fourth time 

 covered a brood-comb, and this time, fortu- 

 nately, the bees let most of the brood re- 

 main in the cells. After an interval of four 

 days, 7 larvte died. An instantaneous and 

 conscientious examination, by aid of the 

 microscope, revealed the presence in their 

 bodies of immense numbers of Micrococci. 



Unfortunately, I was obliged now, on the 

 12th of August,' to defer my experiments, as 

 I could not postpone for a longer time a 

 Bath tour on which I should have started at 

 the beginning of the month. 1 forgot now 

 to slide in a wire netting to prevent those 

 larvae that remained being torn out by the 

 bees, but on my arrival at home from the 

 Baths I found all in the best order. 



Still the fact that Microccoccus possesses 

 an enormous power of infection, and that it 

 also attaches itself to perfectly healthy 

 brood until it kills them, cannot longer be 

 denied. As incomplete (which I myself 

 acknowledge) as the above proof turned out, 

 owing to the scantiness of material that I 

 had at my disposal, and the haste with 

 which I was compelled to operate, as strik- 

 ingly and as unrefutably have I succeeded 

 by another process to prove it. 



As I at once saw beforehand that under 

 the circumstances before mentioned, and 

 the well-known strong propensity of every 

 strong hive of bees to remove as quickly as 

 possible every sickly or dead larva from" the 

 hive, it would be extremely difficult to ar- 

 rive at a complete and satisfactory result, 

 so the idea occurred to nie to try the experi- 

 ment of infection on the larvte of other in- 

 sects, which it would be possible to observe 

 without obstruction. 



As specially adapted for the purpose of 

 this experiment, it occuiTed to me that the 

 larvse of the blow-fly would be the best, as 

 these larvse especially possess an extraor- 

 dinary vitality, that, notwithstanding its 

 voraciousness, it suffers hunger and thirst, 

 and in defiance of its nudity, can withstand 

 cold and heat most astonishingly; and be- 

 sides the above, this insect resembles the 

 »bee in its development, insomuch as it is as 

 larva 14 days, and it is as pupa about the 

 same length of time. I could, without dif- 

 ficulty, procure and nourish these larvae, 

 and, what at that time was of most impor- 

 tance, I could take them with nie to Jolian- 

 nisbath, and there comfortably observe 

 them under the ordeal. 



I, therefore, on the 11th of August, laid a 

 Juicy j)iece of meat in the window, and a fly 

 of metallic lustre, desirous of laying, soon 

 deposited a heap of eggs on it. The next 

 day about 100 were hatched, and these grew 

 with their well known rajtidity. The second 

 day of my stay at Johannisbath, to where, 

 of course, besides these larva^, I brought my 

 microscope, some of the wool that contain- 

 ed the fungus, and also a few bell-glasses, 

 under which latter I placed three separate 

 sets of larvie. 



The first and second had each ten, and 

 the third the remaining larvae. The larvae 

 under tlu; first bell-glass on the same day, 

 together with the meat which was their 

 resort, were covered with wool. Six days 

 after this the larvae attained their normal 

 size, and this without my being able to 



