MAMMALIAN CESTODES. 5 
spherocephalus Rudolphi) the bladder is divided up by trabecule. 
Urocystidiwm is not definitely of any of these types. 
Text-figure 2 represents a transverse section through about 
the middle region of the youngest of the two individuals which I 
have studied. In this region the worm is at its broadest ; there 
is no question of a posteriorly situated bladder, as in the.complete 
immature worm which I described and figured in my former 
paper. The diameter is at most 2°5-2°8 mm. ‘The parenchyma 
is Interrupted by numerous oval to cireular and more elongated 
cavities which occupy the greater part of it. These cavities vary 
in number and size in different regions. The largest number 
Text-figure 3. 
Portion of a transverse section near to that represented in text-fig. 2, but more 
highly magnified. 
e. External surface showing cuticle and subcuticular layer. 4. Cavity lined by 
cuticle, outside which are cells, and corresponding to cavity 4 in text-fig. 2. 
that I have counted in a given section is 17; the smallest 
number——and this occurred only at the two ends of the body— 
is 1. I have found no direct relation between the width of the 
body and the number of cavities; that is to say, the cavities are 
more numerous at one end of the body, which measured only 
2mm. in diameter, than in the section figured, which measured 
nearly 3 mm. 
' But although there is no direct relation of this inal it isa fact 
that it is only at one end of the body that the cavities are most 
numerous. This may possibly, for reasons which wiil be apparent 
