2 ARTHUR E. SHIPLEY. 
The body tapers anterioly, and to a sheht extent posteriorly. There is no true 
neck, the proglottides beginning immediately behind the head; they are at. first 
extremely short from before backward, a feature they retain, though to a lesser degree, 
even at the hinder end, where it takes some three to measure a millimetre. The 
posterior edge of each proglottis overlaps the succeeding one to a marked extent. 
The head is conical, 8 mm. in length and 3 mm. in breadth posteriorly ; anteriorly 
it lessens to a bluntly pointed apex. Dorsal and ventral le the two suckers. These 
suckers are deep, with cleanly cut edges, for the most part curled in (fig. 7), and in 
all cases enwrapping some foreign substance, perhaps a portion of the mucous 
membrane of the host. 
The impressed line running along the whole body, referred to by Baird, is only on 
the ventral surface, and is due to the median opening of the reproductive organs and 
of the uterus. 
The nervous system consists of two very conspicuous nerve cords, which lie parallel 
with the longitudinal excretory canals, and about one quarter the distance of the latter 
from the edge of the proglottis outside the canal. The cords fuse together in the head. 
The longitudinal canals of the excretory system are also conspicuous, and are 
surrounded by thick walls; they break up into an anastomosing tangle of ductules in 
the head. There are also small canals which lie close under the surface at the edges of 
the proglottides, usually two at each side (fig. 2), but they also break up from time to 
time into twisting branchlets. The overhanging edges of the proglottides, especially of 
the posterior ones, are very richly supplied with water-vascular tubules. It is possible 
that these may have a certain hydrostatic action, and serve to erect these free edges 
when fluid is directed into them. 
The confused meshwork of muscles in the head straighten themselves out in the 
neck and fall into regular rows. Of these there are six or seven dorsally and six or seven 
ventrally (fig. 2), but at the sides the rows tend to merge and lose their distinctness. 
Each row is separated from the next by very clear and distinct connective tissne 
fibrils running parallel with one another. The muscles in these rows consist of bundles 
of various sizes containing from six or seven up to fifteen or twenty fibrils. Running 
between every two or three of these bundles are some slight and radially arranged 
connective tissue fibrils, which, with the concentric fibrils of the same nature, serve to 
divide up the tissues into a series of little squares. No muscle fibres penetrate the 
parenchyma within the central area, bounded at the sides by the nerve cords and 
dorso-ventrally by the innermost layer of muscles. 
The penis is conspicuous and very muscular, it opens in the anterior edge of the 
proglottis just where it joins the one in front, and is concealed by the overlapping end 
of the preceding proglottis. Close behind it opens the vagina, and behind this again the 
uterus, all in the middle ventral line. There is a large vesicula seminalis. 
The testes are scattered throughout the parenchyma of the central part. The 
ovary is rather branching ; it lies towards the posterior end of each proglottis, is deeply 
