FUNGOUS DISEASES OP THE HONEYBEE 31 



brood combs were also unaffected. Bees were attacked and killed, 

 however, when the spores of an unidentified species of Penicillium, 

 isolated from mycelium growing in a wound of a living bee, were 

 placed in wounds made with a needle. The infection was at first 

 localized in the wound, but soon spread to other parts of the body. 

 Nothing further could be done with this species though the foUow- 

 mg members of this ubiquitous group of fungi were tested for patho- 

 genicity : Penicillium coTylophuum Dievckx, P. cydopium Westling, 

 P. palitans Westling, P. expanswn Link sensu Thom, P. Gommune 

 Thom, and P. hrevicaule Saccardo sensu Thom. 



Although the spores of the above species of Penicillium did not 

 germinate within the digestive tract of living bees, they remained 

 viable and often germinated soon after the death of the bee, causing 

 mummification of the tissues. This probably accounts for the simi- 

 larity of conditions observed in bees mummified by Penicillia with 

 those conditions observed in bees killed by Aspergilli. 



RESULTS OF EXPERIMENTS WITH THE MUCORS 



Adult worker bees were inoculated with species of the genus 

 Mucor which had been isolated from bees mummified by these organ- 

 isms. They were unaffected in most of the experiments, though an 

 occasional bee was attacked by one species, M. hierrudis Wehmer, 

 when bees were caged on cultures, or when spores of this organism 

 were mixed with dilute honey and fed to them. 



Only an occasional bee was attacked in colony experiments in 

 which most of the honey was removed from the hives and replaced 

 with honey diluted with three volumes of a water suspension of 

 spores of M. hiemalis. The brood in such cases was unaffected. The 

 other species isolated from bees and tested for pathogenicity on bees 

 in cages were M. raoeinosus Fresenius, Rhizopus nigricans Ehren- 

 berg sensu Lendner, and Syncephalastruvi racemoswrn F. Cohn. 

 None of the bees were attacked by these. 



SYMPTOMS PRODUCED BY OTHER FILAMENTOUS FUNGI 



A considerable number of fungi belonging to genera other than 

 those already discussed have been isolated from bees and tested for 

 pathogenicity by feeding spores to bees, or by caging bees on the 

 cultures. Among the fungi tested were Fusarium negundo Hubert 

 and other unidentified species of Fusarium, unidentified species of 

 Sporotrichum, Gladosporivmb herbwnmi Pers, Hormode'ndrwm atmm, 

 Bonord, and MyceliopJithora inflata Burnside. Only negative re- 

 sults were obtained in the experiments with these fungi. An uniden- 

 tified species of Isaria, isolated from a sowbug, and MetmrMziwin 

 anisopliae (Metsch.) Sorokin attacked less than 10 per cent of the 

 inoculated bees. 



Other fungi have been isolated that were found vegetating within 

 the digestive tract or tissues of sick bees. Although the observations 

 made indicated that some of these were pathogenic to the bee, inocu- 

 lation experiments were limited to those forms that appear on bees 

 with considerable frequency. 



