217 
NOTE ON THE SO-CALLED MUSCULATURE 
OF TAENIA ELLIPTICA. 
By WALTER IIEAPE, M.A., F.R.S. 
Trinity College , Cambridge. 
Plate XVII. 
The internal organisation of the Cestoda is described as follows by 
Sedgwick (1898, p. 246): 
“ Beneath the cuticle-like outer membrane is a layer of spindle- 
shaped cells lying at right angles to the surface; their external ends 
abut upon the cuticle, and their inner ends are prolonged as fibres into 
the parenchyma. Beneath this layer there is a delicate superficial 
layer of longitudinal muscular fibres, and next a parenchyma of 
connective tissue in which strongly-developed bundles of longitudinal 
muscular fibres, as well as an inner layer of circular muscles, are 
embedded; both these muscular layers are traversed, principally at the 
sides of the body, by groups of dorso-ventral muscular fibres.” 
In Taenia elliptica a somewhat different arrangement is found 
which, so far as I know, has not been described, except, in part, for 
T. lineata, and which is, I think, worthy of record. Moreover, inci¬ 
dentally, a histological examination of this species throws some light 
on the relationship of contractile fibres to connective tissue cells which 
is not without interest. 
Some of the proglottides of my specimens of T. elliptica were 
preserved in osmic acid, others in a mixture of corrosive sublimate and 
acetic acid. When hardened the osmic specimens were found to be 
flattened and elongated, while the others were shortened and expanded 
dorso-ventrally. Thus the behaviour of the various tissues under such 
different circumstances was to be seen and, owing to the different 
