148 SYDNEY J, DICKSON AND J, T. WADSWORTH. 
attain to a greater size, their arms are longer and branch 
more frequently, and they seem to possess more raicronuclei. 
It is difficult to express the differences between them in exact 
terras. Some specimens from Birmingham are very similar 
to some specimens from the Bridgewater canal, and there is 
Text-fig. B. 
This figure represents the more usual form in which the variety 
of Dendrosoma radians from the Bridgewater canal is 
found. It is attached to the h y drocaulus of a Cordylo- 
phora. The longest of the three arms was 0'5 mm. in length 
and unhranched. The longest suckers are 7.5-90 /t in length, 
c. Cordylophora hydrocaulus. c.v. Conti-actile vacuole. 
undoubtedly a great range of possible variation in specimens 
from both localities. The specimens from Birmingham are 
undoubtedly more closely related to the original type speci- 
mens of Ehrenberg and to those described by Kent than are 
