REPTILIAN TAPEWORMS. 



9 



it, as they have been figured in some other species. Between the 

 layei' of muscles which forms the actual sucker and^the tissue of 

 the body is a considerable plexus or convoluted section of the 

 water-vascular tube not shown in the figure. I should say that 

 I confirm Johnston's statement for Ichthyoicenia tidsioelli as to 

 the spinelets covering the interior of the sucker for the present 

 species. The strong muscles which retract the suckers and the 

 scolex generally are massed in the neck-region of the strobila into 

 a thick layer of longitudinally running fibres, which reduce the 

 medullary region of the body very considerably. The appearance 

 reminds one of Dasyurotcenia robusta, where the neck-region has 

 also particularly stout muscles *. 



Text-fio-. 2. 



Two transverse sections througli the strobila of the same species of 

 Ichthyotania {AcanthotcBnia). 



The upper figure represents the " neck "-region, and shows the strong longitudinal 

 muscle-bundles (M). The lower figure is from the posterior region of the 

 body, and shows the absence of these muscles. T, testes ; on the right are 

 shown other parts of the reproductive system, also in an immature condition. 

 The water- vascular tubes are shown white in both figures. 



The fibres (see text-fig. 2) are collected into bundles of various 

 sizes, which are close together and completely encircle the body. 



See Beddard, P. Z. S. 1912, p. 684., text-fig. 97. 



