STRONGYLUS TETRACANTHUS AND STRONGYLUS ARMATUS. 265 
pearance ; imagine them much distended with air and you 
will have pictured to yourselves their thin appearance. The 
cascum, partly filled with alimentary material in which were 
to be seen the strongylus tetracanthus in great abundance; 
! the mucous membrane of this organ was an interesting study; 
when washed the mucous surface was a mixture of dirty gray 
and olive green in color; the latter I ascribe to the action of 
the iron administered in the powders ; the membrane, cede- 
matous, lacked firmness and was easily torn. Close inspec¬ 
tion of the surface revealed the presence in almost countless 
numbers' of small spots that appeared as reddish or dark 
points. A sufficient number of these were examined to prove 
that each one was or had been the home of a developing te¬ 
tracanthus. Pick an opening into the membrane at one of 
the points and one of the parasites, neatly coiled, could be 
seen. The description of the cascal membrane will do for 
^that of the great colon. 
It would be difficult to estimate the number of these par¬ 
asites lodged within the membrane of the great colon and 
:aecum. Suffice it to say that thousands had been expelled 
and thousands yet remained. 
The membrane of the floating colon contained few, if 
any, of the parasites. So much for the tetracanthus. 
To describe accurately all the lesions (principally of the 
flood vessels) produced by the strongylus armatus would re¬ 
quire a handier pen than mine, but I submit for your inspec- 
:ion a section of the colic artery that will testify very strongly 
;o the destructive work of the armatus when present in large 
lumbers. In the specimen you will perceive there has been 
aresent a severe endo-arteritis, and that instead of a smooth 
ahannel for the passage of the blood there remains a rough, 
acerated and irregular canal through which the blood must 
:reep and wind about to circulate. The arterial wall is 
enormously thickened by hyperplasia of the connective tissue 
elements, the middle coat in particular. Free on the inner 
vail or buried in the arterial tissues, or with head or tail 
irojecting into the blood stream are numerous undeveloped 
trongylus armatus, like the specimen, was the condition of 
