The Occurrence of Diseases of Adult Bees. 9 



some later time a better race of bees is found, provision might then 

 be made for its importation under proper precautions. Prohibition 

 rather than restriction through quarantine would seem preferable 

 because of the high cost of such regulatory measures. At present 

 there is no law which would seem to cover this case, and new legis- 

 lation will be required to safeguard the beekeeping industry of the 

 United States from this pest. It would be quite possible to provide 

 by law for either restriction or prohibition, with the understanding 

 that for the present only prohibition would be enforced. In view of 

 the possibility that desirable races of bees may be found after further 

 explorations have been made, especially in Africa, such a double pro- 

 vision would be desirable. 



NOSEMA DISEASE. 



In 1909 Zander {22, 23) described a protozoan parasite which is 

 found in the alimentary tract of the adult honeybee and to which he 

 attributed serious losses to beekeepers in continental Europe. Zander 

 was evidently misled as to its seriousness. Following the announce- 

 ment of his findings, investigators in all parts of the world began a 

 search for this parasite, and it was soon found in several places in the 

 United States, in Australia, and in various parts of Europe {3, 11, 

 12). From these various investigations information regarding the 

 life history of the parasite was obtained, although some curious mis- 

 takes of observation were made and the literature is not in agreement 

 regarding it. 



As previously stated, some of the earlier work on the Isle of Wight 

 disease in England indicated that it was caused by Nosema apis. 

 This conclusion was reached by Fantham and Porter (5, 6) , although 

 their work contained errors regarding the life history and led to 

 considerable confusion. Assuming that the results of this work were 

 correct, and knowing that Xosema apis is a widely distributed para- 

 site, those interested in bee-disease control naturally concluded either 

 that the reports regarding Isle of Wight disease were grossly exag- 

 gerated or that the environmental conditions in the British Isles 

 resulted in a more serious aspect of the disease than was observed 

 elsewhere. Outside the British Isles there was no proof that Nosema 

 apis causes great losses, although, perhaps misled by the work of 

 Zander and Fantham and Porter, certain other investigators were led 

 to attribute serious conditions to the organism. Those who knew the 

 actual results of Nosema apis infection were inclined to question the 

 results of the British investigators, and, as has been shown earlier, 

 this work is now virtually disproven, in that the mite Acarapis woodi 

 is now believed to be the cause of the Isle of Wight disease. 



While there is a disease of adult bees caused by the pathogenic 

 action of Nosema apis, the wide distribution of the parasite in the 

 United States and the absence of any serious disease of adult bees 



