48 Mr. H. A. Baylis on a new 



network which not only extends throughout the ventral part 

 of the medullary parenchyme, but also penetrates on to the 

 dorsal side. The dorsal longitudinal vessels are not in direct 

 communication, like the ventral vessels, with this system, 

 but, if connected with it at all, are only indirectly so connected 

 (v. Janicki, 1910, p. 394). In Inermicapsxfer hyracis 

 (which is removed by Dr. Beddard to Zschokkeella) there is, 

 according to v. Janicki's account (1910, p. 378), an indirect 

 connection of this kind between the dorsal vessels and the 

 capillary network, and also a very slender vessel running 

 parallel with and external to each main dorsal vessel, and 

 connected with it at frequent intervals by little cros3-vessels 

 like the rungs of a ladder (1910, pi. xiii. fig. 16). 



Von Janicki's figures of the excretory network in this species 

 do not give the impression of a series of almost regular longi- 

 tudinal vessels, connected by a single transverse vessel for 

 each segment, as observed in the species which forms the 

 subject of this paper. On the contrary, the vessels composing 

 the network in Z. hyracis seem to be much more numerous 

 and irregular. 



In my species there is no distinct pair of ventral longitu- 

 dinal vessels of large diameter. The capillary network, 

 which appears to take their place, extends into the middle of 

 the medullary parenchyme, but the dorsal vessels are situated 

 at the extreme dorsal limit of the latter, and are, I believe, 

 entirely distinct from the network. I have not observed any 

 appearance resembling the ladder-like structure described for 

 Z. hyracis, nor even any lateral offshoots whatever from the 

 dorsal vesstds. 



Taking into consideration all the above-mentioned morpho- 

 logical points, I have decided to place the present species in 

 the genus Zschokkeella. It may be defined as follows : — 



Zschokkeella muricola, sp. n. 



Length 9-12 cm. Breadth 3'5 mm. Number of segments 

 230. Scolex wider than neck. Segments all broader than 

 long. The excretory system consists of a distinct pair of dorsal 

 longitudinal vessels and a ventral network arranged on a 

 regular plan, with a transverse vessel in each segment. Genital 

 organs begin to appear in the neck before the segments become 

 clearly defined. Genital pores unilateral, on the left side, near 

 the anterior end of the proglottids / not situated on a promi- 

 nent papilla. No genital cloaca. Testes in two unequal 

 groups, the larger group on the side remote from the genital 



