. Nosema-disease. Bees. NOSBMA-DISEASE. * 9 growth and multiplication of the parasite. The digestive flmds are believed to assist in removing the spore coat. The liberated young parasite finds its way to the walls of the stomach and invades the epithelial cells. Within this epithelial tissue it grows and multiplies with great rapidity, giving rise finally to numerous spores. The cells of the epithelium at times seem to become virtually filled with the parasites (fig. 3; Pis. II and III). That portion of An epithelial cell that is normally shed into the lumen of the stomach in case of infection
. Nosema-disease. Bees. NOSBMA-DISEASE. * 9 growth and multiplication of the parasite. The digestive flmds are believed to assist in removing the spore coat. The liberated young parasite finds its way to the walls of the stomach and invades the epithelial cells. Within this epithelial tissue it grows and multiplies with great rapidity, giving rise finally to numerous spores. The cells of the epithelium at times seem to become virtually filled with the parasites (fig. 3; Pis. II and III). That portion of An epithelial cell that is normally shed into the lumen of the stomach in case of infection bears with it many spores. These are liberated gradually from the fragments, become mixed with the partially digested food of the stomach, and are carried onward first into the small and then into the large intestine and finally pass out of the alimentary tract with the excrement. Other bees ingesting these spores become infected. This in brief is the^ife cycle ^ ^through which the parasite passes. jNosema apis reaches the tissues of the bee by way of the ahmentary tract. In infecting the stomach the parasite reaches the basement mem- brane but does not penetrate it (Pis. II and III). The muscular part of the organ is therefore iminvolved (fig. 3). Likewise when the infec- tion is found in the Malpighian tubules the germ does not proceed , ji-UT, i. T.' â¢^*'- *â âSpores of Nosema apisas seen in a fresh beyond tne basement membrane preparation, indicating their general oval form. (Pis. II and III). Furthermore the (0"gi°ai) germ does not infect (fig. 1) the pharynx (P%), the oesophagus {(E), the honey sac (HS), the proventriculus {Pvent), the small intestine, or the large intestine (Beet)âoigans which possess a pronounced chitin- ized intuna. Infection with the parasite seems, therefore, to be con- fined to the epithelium of the stomach and of the Malpighian tubules. So far the writer has not encountered the germ in the blood, muscu- lature, or any of the other ti
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisherwa, booksubjectbees
