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quently contains numbers of an entozoon, which I have 
named Distoma vagans. 1 The blood-vessels, especially 
in the liver, exhibit a white, opaque appearance, which 
is dependent upon the deposit in the sides of the vessel 
of innumerable, oil-like granules. 
The blood contains numerous blood-corpuscles, -which 
vary in size, are granular, and exhibit numerous radiat- 
ing, projecting points of variable length, — frequently 
greater than the diameter of the corpuscle. 
The pulmonary cavity is lined with a tessellated epi- 
thelium, the cells of which are faintly granular, with a 
few coarser granules, and a distinct, round or oval, gra- 
nular, nucleolated nucleus. 
The renal organ is a gland which exhibits a foliated, 
or plicated appearance, within a capsule. The surfaces 
of the plicce communicate with the duct existing along 
the whole right border of the organ, and are covered 
with polygonal, organic cells, every one of which con- 
tains a large, white, round, opaque mass, resembling- 
uric acid in appearance. 
Chapter ix. — on the nervous centres, and the 
distribution of the nerves. 
The nervous centres consist of three distinct sets of 
ganglia, which are all placed within the anterior part of 
the body or head. 
The first set, or supra-cesophageal ganglia, form a trans- 
1 See Journal Acad. Nat. Sci. New Series, Vol. I. 
