NORTHUMBERLAND AND DURHAM. 235 
the umbrella, the fourth produced into a club-shaped 
tentacle, apparently not capable of much extension. The 
peduncle is rather long and thick, terminating in a plain 
rounded mouth. 
These medusoids were produced from one only of the individ- 
uals obtained; the other had gonophores of a different shape, 
having tuberculated lobes rising somewhat irregularly from the 
upper part, as represented in fig. 5. These reproductive bodies 
were also sessile, and remained attached during the whole time 
that the polype continued to live—about ten days—without 
shewing the least signs of assuming the medusoid form. Indeed 
their appearance was very different from that of the same organs 
in the medusa-bearing individual, and I have little doubt of 
their remaining permanently fixed. This difference in the re- 
productive organs in different individuals of the same species 
has not been before observed, as far as I am aware, in this 
genus. They probably represent a sexual distinction. Professor 
Sars has met with a Corymorpha on the Norwegian coast (C. 
glacialis, Sars), in which the gonophores are persistent, and 
apparently somewhat similar to the non-medusoid form of this 
species, but in the Norwegian zoophyte both sexes were found to 
have the same character. | 
Famity. SERTULARIADA, Johnston. 
8. HALECIUM, Oken. 
4. H. taBrosum, Alder. 
Ald. in Trans. Tynes. Club, v. iv., p. 178, t. xii. 
This species has not been met with again since the notice of 
it appeared in these Transactions. 
5. H. Tenetium, Hincks. 
Hincks in Ann. Nat. Hist., 3rd ser., v. viil., p. 252. 
t. vi, f. 1—4. . 
Parasitical on other zoophytes from deep water; occasion- 
ally. 
I had at first considered this as probably a very young state 
VOLS Ve 9 PT UK. : 2D 
