342 BENEDICT. [Vol. XVI. 



.80 mm. in dorso-ventral, and .85 mm. in length (PI. XVI, Figs. 

 I and 2). From the anterior face it presents a nearly square 

 outline, with a deep notch in the middle of each side, dividing 

 the surface into quarters. Each quarter contains a large sucker 

 which is directed outward and upward. The apex of the head 

 is a smooth, rounded prominence with a small depression in the 

 top (PI. XVI, Fig. 3). No hooks are present. A fairly good 

 idea of the shape of the scolex can be obtained by placing two 

 truncated pyramids base to base. One of the smaller bases will 

 represent the beginning of the neck, the other the prominence, 

 while on the slope just beneath this would lie the suckers. 

 The notches seen in the anterior view of the scolex form fur- 

 rows down the four sides of the head, which gradually decrease 

 in depth and vanish on the first few proglottids. 



The surface of the proglottids is very rough, being thrown 

 into longitudinal and transverse folds, as shown in the margin of 

 PI. XVI, Fig. 4, where the transverse furrows are so deep as 

 to obscure the divisions between the proglottids. The pro- 

 glottids are also closely joined together, so that it is difficult to 

 distinguish the divisions between them. The color of the body 

 in the alcoholic specimen is a watery white, with a yellowish 

 tinge toward the posterior end. 



A small genital sinus, having a depth of .025 mm. and a 

 diameter of .05 mm., is situated about one-fourth the length of 

 the proglottid from the anterior end, on the margin. It is 

 irregularly alternate in position (PI. XVI, Fig. 4). 



Anatomical and Histological Structure. 



Cuticula. — The cuticula can be resolved into two layers ; 

 an outer thinner portion, .0015 mm. thick, forms the external 

 surface (PI. XVI, Fig. 11, ct^ ). It is very rough, with minute 

 projections extending from the surface, which are coarser, 

 blunter, and more irregular than cilia, and which stain darkly. 

 Within this layer is another, .0075 mm. thick, which appears 

 nearly homogeneous (PI. XVI, Fig. 11, ct). This does not 

 take the stain so vigorously as the first. Within the cuticula 

 is a layer of transverse muscles, .001 mm. thick, which appears 



