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Taenia elliptica 
stretched and appear as delicate gossamer fibres hardly distinguishable 
from the connective tissue and apparently of the same consistency. They 
are markedly different from the osmic specimens, being swollen and 
indistinct instead of wiry and of sharp contour. The same change, only 
still more marked, is seen in both groups of the longitudinal fibres ; 
here there is no indication of separate fibres, they are swollen into a 
mass which is but faintly indicated, by shading, in my drawing. 
This swelling under the influence of acetic acid is an attribute of 
white fibres and, when it is remarked- there is no indication of anv 
muscular structure in any of the fibres, it becomes exceedingly probable 
they are white fibres and not muscle fibres at all. 
But there is another point; the dorso-ventral and circular fibres are 
each connected at one point, in the central section of the body, that is 
to say about the middle of their length, with a mass of protoplasm 
surrounding a large nucleus. The protoplasm is attached to the fibre 
but not enclosed in a sheath, as some observers have stated (see Pintner, 
1881, p. 163), and this is to be seen in specimens preserved both in 
osmic acid and in corrosive sublimate and acetic acid. It is clearly 
shown in Figs. 3 and 4 ; in some cases the protoplasm surrounding the 
nucleus is attached to the fibre at two separate points (Fig. 3), in other 
cases it appears to lie flat on the fibre, but in all cases the fibre is quite 
sharply marked off from the nuclear protoplasm. A similar condition 
is seen in Fig. 2, but here, under the influence of acetic acid, the fibre 
itself is swollen and merges somewhat into the nuclear protoplasm. 
The continuity of these contractile fibres with the cells from which 
it appears obvious they were derived, is an important matter in view 
of what I have to say below. 
Finally in Figs. 3 and 4, the dorso-ventral and circular fibres, which 
are contracted, are seen to be spirally contracted. This is a very 
remarkable condition and so far as I know it has not been described in 
any cestode. Wavy contractions have been described, but not spiral. 
I examined my specimens for long under various powerful lenses, using 
Reicherts t l, Zeiss and and Powell and Lealands immersion 
lenses, before determining this point. I have however now no doubt 
whatever that what at first sight looked like the wavy contractions 
described by the older observers, are really spiral contractions. This 
phenomenon I have endeavoured to show in figs. 3 and 4. They were 
drawn (as were all the figures) with the aid of the camera lucida, and 
are as exact as I could make them; it is perhaps best shown in Fig. 4, 
where here and there I think I have succeeded to some extent in 
