28 H. B. FANTHAM. 
that he rather emphasises the distinction between periplastic 
appendix and chromatic border. Further, he does not 
mention the contractile fibrils actually found in the “ peri- 
plast appendix,” which fibrils appear to stain like chromatin, 
for they are plainly seen with gentian-violet and iron- 
hematoxylin. After staining normal specimens with the 
Giemsa and Leishman colorations these fibres are not plainly 
seen, and that probably accounts for their being overlooked 
by Perrin. But in the case of disintegrated specimens 
similarly stained these fibrils can be seen, after patient 
observation, as faintly pink staining threads (Pl. 1, fig. 10). 
I have tried the effect of various reagents on the peri- 
plast, but will postpone any discussion of the results to a 
later and separate section. 
Regarding the endoplasm, which is not easily differenti- 
ated from the other structures, I can only add that it 
does not appear to contain any vacuoles or enclosures, at 
any rate in normal specimens. It stains blue with Giemsa’s 
coloration. 
The Membrane. 
This characteristic structure of the genus Spirocheta 
has been already discussed in brief, and the following 
description is given in addition or extension :— 
It is a spirally-wound lateral extension of the periplast 
with a thickened border, and is composed of almost longi- 
tudinally arranged fibrille running nearly parallel to the 
chromatin border (see Pl. 1, fig.5; Pl. 2, fig. 27). Though 
nearly longitudinal in disposition, these fibrils probably run 
with a slight obliquity, as diagrammatically represented in 
text-fig. 5.1. These fibrille are contractile, and probably con- 
tract one after the other in very nue succession. ‘They 
may be termed “ myoneme fibrille,” though the term 
1 Although the myoneme fibrils may sometimes appear rather more oblique 
in some of the figures (e.g. Pl. 1, fig. 3, lower end), this additional obliquity 
is due to the spiral winding of the membrane, and to its pe folding (PI. 
I, figs. 2, 5a; Pl. 3, fig. 20). 
