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V. On the Anatomy and Histology of the Land-Planarians of Ceylon , with some 
Account of their Habits , and a Description of two new Species , and with Notes on 
the Anatomy of some European Aguatic Species. By H. N. Moseley, M.A. Oxon. 
Communicated by G. Pollestox, M.D., Professor of Anatomy and Physiology in 
the University of Oxford. 
Received January 16, — Eead February 20, 1873. 
Preface. 
At the outset I would desire to express my deep obligations to Professor Pollestox in 
the matter of this paper. I was first informed of the existence of Land-Planarians in 
Ceylon by Professor Pollestox, and of the importance of investigating the correctness 
or incorrectness of Schmaeda’s description of a ganglionated nerve-cord in Sphyrocephalus , 
to which Professor Pollestox has referred in his ‘ Forms of Animal Life,’ as have also 
many other authors. Professor Pollestox at first agreed that the paper should be a 
joint one, and himself prepared a large number of sections of Bhyncliodemus , one of 
which is figured, but subsequently decided that my name only should appear in the 
matter. I have to thank him for suggestions and assistance rendered during the whole 
of the investigation, which took more than two months’ constant work, and also for help 
in the getting up of the bibliography of the subject. The work was done in the Ana- 
tomical Department of the Oxford Museum. 
The Land-Planarians the anatomy and histology of which are described in the present 
memoir were obtained in Ceylon during the months of January and February last year 
(1872) by the author, in the Poyal Botanic Gardens, Peradeniya, Ceylon, through the 
kind assistance of G. H. K. Thwaites, Esq., F.P.S., the distinguished Curator of those 
Gardens. 
The Planarians are forms of very great interest, as lying in the stem of the family-tree 
of the animal kingdom at a point where very many branches are given off by it. Bipa- 
lium and Bhynchodemus, as being the largest of known Planarians, offer especial advantages 
for an accurate and complete investigation of their anatomy ; and a thorough knowledge 
of the anatomy of these larger forms cannot fail to throw great light on that of their 
smaller congeners. It is also of extreme interest to see how far largeness of size and 
difference of habit is accompanied by corresponding modifications of structure in forms 
such as these. The published accounts of the anatomy of Bipalium and Bhyncliodemus 
are, as will be seen in the sequel, imperfect and, in many very important particulars, 
mdccclxxiv. p 
