224 



AMERICAN BEE JOURNAL 



July 



«<3 



%M 



Fig. 8.— A magnified cross-section of a stom- 

 h h shown in Fig. 2. The germs are stained 

 black. Note that >"ine of the germs have 

 been shed into the stomach and are mixed 

 with its contents. 



colonies. This fact led to the request 

 made of beekeepers, in different sec- 

 tions of the country for adult bees 

 from weak colonies. Out of about 150 

 samples received in reply, fully one- 

 half of them contained Nosema-in- 

 fected bees. Nine well-informed bee- 

 keepers, among those sending sam- 

 ples, were asked concerning the name 

 by which the disease condition was 

 known to them. Of these 3 replied 

 "spring dwindling", 2 "not spring 

 dwindling", 2 said "weak colonies," 

 and 1 wrote, "I don't know." 



Bees from spring dwindling colo- 

 nies were requested also from bee- 

 keepers. Out of 38 samples received, 

 only IS contained Nosema-infected 

 bees. In reply to requests for bees 

 from hives in which colonies had 

 died during the winter, 19 samples 

 were received and 7 of them con- 

 tained Nosema-infected bees. Out of 

 5 samples taken from colonies which 

 beekeepers had diagnosed as suffering 

 from paralysis, no bees were found 

 infected. 



From these facts it will be ob- 

 served that no one name was being 

 used, by American beekeepers, for the 

 condition to which the losses due to 

 Nosema-disease were attributed. 

 Some, it will be seen, referred to the 

 condition as spring dwindling, but 

 others did not. That the disease con- 

 tributes in part to winter losses is 

 quite evident. It is an interesting 

 fact that neither paralysis nor dys- 

 entery was suggested, by beekeepers, 

 for the condition in colonies in which 

 Nosema-infected bees were present in 

 large numbers. 



When Zander reported his obserya- 

 n 1909, he used the name "in- 

 fectious dysentery." This name was 

 misleading, and fortunately he soon 

 afterward introduced another one, 

 which is mure appropriate. \- the 

 on name for the disease, in 

 English, the writer has suggested the 

 term "Nosema-disease." This is sim- 

 ply a translation of the more appro- 

 priate name given to it by Zander. 



That the following nanus have been 



used, in one or more countries and 

 from time to time, for the disorder 



that is produced by Nosema apis, is 



very probable: Dysentery, paralysis, 



palsy, spring dwindling, dropsy, dis- 



ring trick and Isle of Wight 



disease. To this list the beekeeper. 



most likely, could add many more. It 

 is not at all probable, however, that 

 any one of these had been used ex- 

 clusively for the disorder now known 

 as Xosema-disease. Whether the dis- 

 eases of adult bees are few or many 

 is not definitely known, but it seems 

 probable that they are fewer than are 

 the names which have been used for 

 them. Practical beekeepers have 

 made some interesting observations, 

 on the adult bee diseases, but it must 

 be admitted that very little of a defi- 

 nite character has yet been obtained, 

 from an experimental and laboratory 

 study of these diseases, excepting 

 Nosema-disease. 



A word should be said in regard to 

 Isle of Wight disease, in order to al- 

 lay any possible uneasiness which 

 might be felt in America regarding it. 

 The writer has not encountered, dur- 

 ing his studies, any condition which 

 causes the losses which have been at- 

 tributed to Isle of Wight disease in 

 England. Certainly Nosema-disease 

 does not cause such losses in Amer- 

 ica. Since the Isle of Wight disease 

 does not seem to be in America, fear 

 by American beekeepers is scarcely 

 justifiable at the present time. Stu- 



dents of the disease in Great Britain 

 no doubt will supply, in due time, as 

 a result of their investigations, the 

 information on the disease which is 

 wanting. 



..keepers will recall the technical 

 name, "Microsporidiosis," which has 

 been used for the disease caused by 

 Nosema apis. This name was chosen 

 because Nosema apis belongs to a 

 group of protozoa "Microsporidia." 

 While the name is appropriate, some 

 criticism has been offered by bee- 

 keepers, because of its length and be- 

 cause it is not readily understood 

 l'.\ way of explanation of the term. 

 it might be said that the term "nose- 

 mosis" could have been coined and 

 used as the technical name in much 

 the same way I he origin of the lat- 

 ter term will be readily recognized. 

 The Experimental Apiary 

 Much concerning tin- nature of No- 

 di . i . has been learned by ob- 



■ I'u ing ii in i In- experimental apiai ) 

 The space occupied by the apian (fig 



7 I was broken up by small trees. In 

 arranging the hives, uniformity as to 

 their relation to each other was in- 

 tentionally avoided. A nucleus which 

 could he accommodated comfortably 

 on from 4 to 6 brood-frames was 



found to serve well the purposes of 

 an experimental colony. The en- 

 trance to the hive (fig. 8) was closed 

 except a small space on the side occu- 

 pied by the frames with wire cloth. 

 Shallow dishes placed on the bottom- 

 board on the side occupied by the 

 brood-frames were used as feeders. 



At the beginning of the experi- 

 ments all of the colonies of the api- 

 ary were free, or practically free, 

 from Nosema infection. In making 

 the inoculations the experimental 

 colonies were fed about one half 

 pint of sugar syrup, to which had 

 been added the crushed stomach of 

 Nosema-diseased bees. These colonies 

 were left in the apiary and were not 

 confined, but were allowed to enjoy 

 the same freedom after the inocu- 

 lation as before. 



How to Examine Bees for Nosema- 

 disease 



Upon examining a large number of 

 young bees it was observed that 

 among them there were practically 

 no Nosema-diseased ones. The same 

 was found to be true of the very old 

 bees. In making the examination, 

 therefore, for Nosema-disease in 

 colonies, bees that were neither very 

 young nor very old were selected. As 

 drones are not likely to be found in- 

 fected, except in experimental colo- 

 nies recently inoculated, they were 

 not chosen in making the examina- 

 tions. As the brood does not become 

 infected, it cannot be used. 



The younger bees may be avoided 

 by selecting field bees and the very 

 oldest ones may be omitted from the 

 samples taken by avoiding those that 

 are shiny. It was found that for most 

 purposes 10 bees make a very satis- 

 factory sample for examination. The 

 bees are taken at the entrance of the 

 hive. Those carrying pollen, if pollen 

 is being brought in, are the ones 

 chosen, as they are readily recog- 

 nized as field bees. As an individual 

 bee, sick of Nosema-disease, presents 

 no outward evidence of disease, and 

 since only by the changed appearance 

 of the stomach can the disease be di- 

 agnosed, the bee must be sacrificed in 

 making the diagnosis. They are 

 caught by the thorax with forceps 

 and by slight pressure are easily 

 killed. " 



In removing the stomach, the tho- 

 rax is held between the thumb and in- 

 dex finger of one hand, and with finc- 

 pointed forceps (preferably curved) 

 in tin other, the tip of the abdomen 



Fig. 



Shows ;■ still higher magnification 

 than Fig I. 



