242 S- ^OTO. 



Posterior siicher circular, large, with a diameter equal to half the 

 length of the body proper ; projecting beyond the body by about one- 

 third of its diameter, Avith a marginal mem])rane ; central area a 

 nine-sided polygon formed by bringing the shorter of the two parallel 

 sides of an isosceles trapezoid on one side of a regular heptagon and 

 by obliterating the boundary (/. p., central heptagon open behind), 

 and with the added trapezoid projecting backwards ; peripheral 

 areas seven in number, the four anterior of equsd size, with the 

 form of an isosceles trapezoid, the next two on either side of a 

 different form from the others, l)ut similar to each other, with 

 the form of an isosceles trapezoid with one of its corners cut off 

 oblicpiely ; and the hindmost area which occu[)ies the median line 

 again with the fonn of an isosceles trapezoid, but much smaller than 

 the others. Hooh'; in one pair, solid, flattened, witli a ft:)rm like that 

 of the butcher's knife (PI. XXIII, tig. 2), longitudinally furrowed, 

 with a deep notch at the proximal end, large, being 0.91 mm., imbed- 

 ded in the non-parallel sides of the isosceles-trapezoidal portion of the 

 central area. Mouth at some distance from the front end of the body, 

 between the anterior suckers, a little anterior to the plane of their 

 hinder ends. Phanjux double, /. e., divided Ijy a deep constriction 

 into an anterior, larger portion and a posterior, smaller portion, so that 

 the whole has somewhat the form of the numeral 8. Oesophagus very 

 short. Intestinal trunhs continuous Avith each other posteriorly a 

 little behind the anterior end (jf the posterior sucker, enclosing a 

 rather small, rectangular area; each with a small number (5) 

 of Literal, repeatedly ]ji furcating branches on the outer side, 

 and only about three shorter branches on the inner. Penis 

 exceedingly large and long, cylindrical, often projecting beyond 

 the opening of the genital atrium. (Jcanj sulj-globular, much 

 lobed. in the median line, at the hinder end of the anterior 



