A revision of the adult cestodes of cattle, sheep and allied animals ... / by C.W. Stiles ... and Albert Hassall.

  • Charles Wardell Stiles
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: A revision of the adult cestodes of cattle, sheep and allied animals ... / by C.W. Stiles ... and Albert Hassall. Source: Wellcome Collection.

    39/174
    (5) Moniezia oblongiceps sp. n.; 1803. [L’lato VII, Figa. L-4.] Host.—Coaxsus sp. (S. & IT.) Geographical distribution.—Washington, I). C.; imported, from the Island of Trinidad, South. America. Ilia post-mortem examination of a Coassus spf recently imported for the National Zoological Park at Washington, D. 0., from South America, two specimens of an adult cestode were found which bear a great resemblance to M. expansa, but which differ from it in the form of the head and segments as well as in general appearance. While for a long time we were inclined to look upon this as a simple variety of M. expansa, we incline at present to the view* that the para- site in question represents a distinct species, which, however, is very closely allied to M. expansa of cattle and sheep. If only a few seg- ments of the worm were in our possession we should undoubtedly determine them as identical with that form, but with two well pre- served specimens before us it has been decided that they represent a true species. ANATOMY. General appearance.—Two strobihe provided with heads measured respectively 97cin and 88cm in length. A third strobila, which evi- dently belonged to one of those provided with a scolex, measured 31c long. The head is not distinctly separated from the neck; the segments gradually increase in breadth to 50cm from the head, where they reach the maximum of 9mm; from this point they diminish in breadth and increase in length so that the end segments measure 6.5 x lm,u. All the segments are quite thin. When fresh the worms have a very light yellowish tinge. Scolex.—The head measures (preserved) 0.48-0.56mni broad 5 it is somewhat narrower in its dorso-ventral diameter. The same measure- ments are preserved for a short distance back of the head, so that the latter is not distinctly separated from the body. While the head ot M. expansa viewed en face is more or less square, this head is distinctly oblong. The suckers (0.19 in diameter) are situated at the four corners. The openings in our specimens are slit-form and directed halt forward, half corner-wise. The suckers are not so distinctly raised as in M. expansa. In big. 2/>, Plate vit, the portion back of the head is broader than the head: in another specimen (Plate vii, Fig. 2), the diameter of the head is preserved tor about 2, then it decreases somewhat for a very short distance, and finally increases again. This variation is due entirely to contraction.