CLAVA C011NEA. 5 



vesiculosus; and this seaweed is the common habitat of 

 the British species that I have identified with it. 



In C. squamata the polypites are closely massed together, 

 and form colonies on the fronds of the Fucus, the larger of 

 Avhich measure about half an inch across. They are tall, 

 and expand from the base upwards, thickening considerably 

 towards the tentacles. Under the microscope the body 

 appears lineated longitudinally, especially in the older 

 polypites. The tentacles are pellucid white, and number 

 about twenty in the adult *. The gonophores hang in 

 large bunches below the posterior tentacles, and form a 

 massive and conspicuous collar. Individually they are of 

 considerable size, and almost spherical in form. 



The crust that supports each colony is made up of many 

 tubes massed together ; and the upper surface of it is com- 

 pletely covered with the cup-like extensions of the poly- 

 pary, from which the polypites rise ; these give it a honey- 

 combed appearance when the polypites are removed. The 

 tubes are of extreme delicacy, and composed not of solid 

 chitine, but of a soft membranous material. The colonies 

 do not generally stand alone : the tubular basis sends oft' 

 slender, filamentary prolongations, which creep along the 

 weed and give rise at intervals to new clusters. 



Had. Queensferry, Firth of Forth, on Fucus vesiculosus 

 (T. S. W.) : Lerwick, low water, on the same weed (A.M. N.) . 



[Denmark, on Fucus vesiculosus (Miillcr) .] 



3. C. CORNEA, T. S.Wright. 



Eclin. New Phil. Jouni. (N. S.) for July 1857, pi. ii. fig. 4. 



Plate I. fig. 3. 



POLYPITKS clustered, slender, slightly tapering, of a rc<idis1i- 



* Muller jiive.* I lie number 0-10. 



