ISLE OF WIGHT DISEASE IN HIVE BEES — PATHOLOGY. 
759 
The Alimentary System. 
As regards the alimentary system, the investigation has but little to add to'’ the 
observations of former workers. The disordered condition of the alimentary tract 
has attracted much attention in the search for a clue to the causation of Isle of 
Wight disease. 
The facts may be briefly outlined. 
In the majority of crawling bees the hind gut and small intestine are distended 
to the limit of their capacity with accumulated faeces, and the contents of the lower 
region of the chyle stomach may contain a large admixture of faecal matter. The 
chyle stomach itself may present a rather wasted appearance, and its contents may 
be of an unusually deep purple colour. These changes are in all probability merely 
due to a reduction in the fluid contents of the organ. 
In the vast majority of crawling bees no lesion is to be found in the alimentary 
wall either macroscopically or in stained sections. On two occasions only have signs 
of penetration of the wall by organisms (other than Nosema) been noted. In one 
case there was an infiltration of the wall near the insertion of the Malpighian tubules 
by a large filamentous bacillus ; in the other case fungal hyphrn had invaded the 
epithelium of the lower portion of the chyle stomach. Such phenomena are to be 
regarded merely as terminal infections. 
The flora of the alimentary tract of the normal bee has been carefully investigated 
and compared with that of bees crawling from the disease. Very little qualitative 
difference- has been found between the two. 
In Isle of Wight disease there is a colonisation of the chyle stomach by the 
intestinal organisms, and certain organisms, such as coliform bacilli and yeasts, are 
more frequent and abundant than in healthy bees. Certain streptococci, to be 
described elsewhere, have also a predilection for the alimentary tract of Isle of 
Wight bees. 
Malpighian Tubules. 
In a proportion of crawling bees certain of the Malpighian tubules, when mounted 
in saline, may possess a bright yellow colour due to the presence of large amounts of 
the excretory pigment. In these coloured areas the excretory granules within the 
epithelium may be abnormally large and spicular. In fresh preparations the cells 
appear to be filled with large bacilli. A similar condition may arise in bees after a 
period of confinement. 
Nervous System. 
The examination of the nervous system for pathological changes is as yet very 
incomplete. The observations of the writer have been mainly restricted to the 
thoracic ganglia. No changes have been noted in the posterior thoracic ganglionic 
