BEANCHIOCEEIAMTHUS I3IPERAT0K (aLLMAN). 255 



that of the hydranth. Thus these two axes make in B. ur- 

 ceolus an extremely obtuse angle as in A, and thus lielp to 

 produce the vase-shape. In our specimen the angle which 

 these two axes make with each other (B) is much less obtuse, 

 and moreover the folding in of the disc margin has not been 

 noticed from the first, either in the fresh or preserved state. 

 The disc lay flat and open as a disc, and never suggested the 

 idea of a pitcher. 

 b. The shape of the disc is oval in B. urccolus ; in our specimen 

 it is more nearly circular. Moreover in the former, the 

 sagittal or longitudinal diameter is greater than the trans- 

 verse, while in our specimen it is the transverse diameter 

 which is the greater of the two. The following measure- 

 ments will make this point clear. 



Sagittal (longit.) diam. Trans, diaiii. Ratio of trans, 



in mm. in mm. diam. to sagittal. 



B. urceolus. 



Small specimen.,, 25 1.5 60% 



Large specimen . . .38 30 nearly 79^ 



iS'colle,^-- SO 00 112.5»/, 



c. The size : — 



T M c i\ 11 Maximum length Maximum length 



Length of the Jivdro- ,. ,, . " , ~ ., i * ? i 



'' 1 . " oi the marginal ot the oral tentacle 



caulus in mm. . i • ° 



ternacle in mm. in mm. 



B. urceolus 105-200 125 30-35 



Specimen of nnç) oqq 50-t"'i 



Science College ^^^ '^^^ '^^ '^'^ 



d. The lower end of the hydrocaidus : — Mark describes a bulb at 

 the lower end of the hydrocaulus. In our specimen, there 

 is no such sudden enlargement as deserves the name of a 

 bulb, although that end is, as has been stated, the largest. 



