117 



in front of the ovary aud great nerves, and is almost entirely con- 

 cealed from view by the innumerable tortuosities of the oviduct. 

 It has four distinct coats, an internal niucous, an external serous, 

 and two muscular layers, one running vertically and the other hori- 

 zontally ; both of which consist in great part of the striated variety 

 of muscular fibres *. The interior of the ahmentary canal is marked 

 by longitudinal rugse, from the surface of which long pyriform villi 

 project. 



Nervous System. — The distribution of the nervous system of this 

 highly organized Entozoon is, in some respects, identical with that 

 fomid in the Linguatula tcenioides, so beautifully described by Pro- 

 fessor Owen. The large ganghon, or brain, is situated olose to the 

 mouth, and is intimately conuected with the oesophagus, to whieh it 

 seems to send two filaments (PI. XLVI. fig. 4, b). I could not, 

 however, satisfy myself of the existence of an ossophageal ring. 

 The distribution of the large pair of nerve cords, which extend almost 

 throughout the whole leugth of the body, differs very materially from 

 that fouud in the Linguatula tcenioides ; for, after passing over the 

 fallopian tubes, instead of running down the sides of the ventral 

 aspect of the body, they continue along the dorsum, behind the ali- 

 mentary canal and close to the ovary (PI. XLVI. fig. 4, c). They 

 are at lašt gradually lošt sight of a few lines above the anus. 



Organs of Reproduction. — In attempting to describe the organs 

 of reproduction in this animal, I shall begin at the vagina and trace 

 them gradually upwards, for it was by following this course that I 

 was enabled, with the aid of the microscope, to distinguish the dif- 

 ferent organs, and to ascertain the function of their various parts. 



The orifice of the vagina is situated immediately in front of the 

 anai aperture (PI. XLVI. fig. 4, d). The vagina itself is about the 

 thickness of a pin, and from 3 to 6 lines in length ; it gradually 

 widens out into the oviduct, or more correctly speaking, the uterus 

 (PI. XLVI. fig. 4, e). For about the first C inches the uterus has 

 a greater diameter than the alimeutary canal ; it then however be- 

 comes gradually narrower, till its diameter does not exceed that of 

 a fine knitting-needle, and contiuues of this size till within a few 

 lines of its termination, where it contracts still more. At its upper 

 point of attachment, vvhich is opposite the third or fourth ring, its 

 diameter is not greater than that of the vagina. In two of the speci- 

 mens I measured the length of the uterus, and found it to be 

 40 inches from the orifice of the vagina to the place of its attachment 

 opposite the third or fourth ring. Thus it is seen to be nearly ten 

 times the length of the entozoon in vvhich it is coiled up. Although 

 it conceals the alimentary canal, it is not, as in the case of the Lin- 

 guatida tcenioides, coiled round it ; neither has it the ferruginous 

 tint spoken of by Owen as belonging to the oviduct of the latter 

 species. It is, on the contrary, of a pale straw-colour when fuU of 

 ova, and almost quite colourless whcn empty. Its parietės are thin 



* Ficinus and Valeiitia found indistinctly striated muscular fibres in thehuman 

 stomach. 



