468 
Spiroclimta gallinarum 
parasite appears to consist of a thick cell-wall (periplast) surrounding 
a homogeneous core which, from its staining reactions, seems to consist 
of chromatic material. 
At certain periods, especially after being ingested by the tick, the 
endoplasm of the spirochaete breaks up into a series of darkly staining 
bodies (Fig. 2 c), -which become rounded off in the form of minute 
coccoid bodies or spores, contained within the cell-wall (Fig. 2 d). 
These coccoid bodies then escape by rupture of the cell-wall and appear 
in the plasma as round, or ovoid, chromatic-staining bodies, the 
diameter of which is usually about 0'2 fx. The true nature of these 
bodies is problematical, for although in some respects they resemble 
the spores of bacteria—especially the Disporea —in their formation, 
yet the fact that they stain deeply and also multiply (see below), at 
once differentiates them from true spores. From their shape and sub¬ 
sequent behaviour, it is preferred to call them “ coccoid bodies ” and 
their nature will be discussed in a future communication. 
The development of these coccoid bodies into spirochaetes has not 
yet been observed in the blood of the fowl, as the spirochaetosis of fowls 
rarely assumes the relapsing type. It has been followed, however, in 
the body of the tick and will be described under that section. 
I have not been successful in observing the penetration of the 
spirochaetes into the red blood corpuscles in the manner described by 
Prowazek (1906), but from their behaviour in the tick it is quite 
possible that it may occasionally take place. The transformatioti of 
spirochaetes into the intracorpuscular bodies of Balfour (1909) has, 
therefore, not been observed, although these bodies have been met with 
occasionally. 
A careful examination of a number of normal fowls has revealed the 
fact that occasionally intracorpuscular bodies, identical in appearance 
with those described by Balfour, may be found in the red cells, and 
consequently it is extremely probable that they are the pi'oducts of 
nuclear degeneration. The fact that the nucleus, or its contained 
nucleolus, may bud off fragments into the cytoplasm is well knovvu and 
also occurs in the red cells of normal fowls. That the appearance 
of numbers of these bodies is associated with an attack of spirochaetosis 
is no more significant than the fact that haemolysis accompanies an 
attack of piroplasmosis. It is known that nuclear degeneration of 
certain cells is associated with some diseases (e.g. rabies; Acton and 
Harvey, 1911) and, therefore, there is nothing improbable in the view 
that the intracorpuscular bodies of Balfour are of this nature. It is 
