276 POLYZOA INFUNDIBULATA. 



— The entire polypiclom rarely exceeds half an inch in length, but 

 when perfect the branches are bent and intertwined so as to form a 

 little glomerous mass. 



" Incipit semper duplici lacinia, veluti furca, obliqua a rupe aliave 

 cui insidet basi prodeunte. Lacinice nunquam 2 lineis paris. lon- 

 giores observantur." Pallas, 



Milne-Edwards is of opinion that the T. serpens of 0. Fabricius 

 is not synonymous with the Linnoean species, but with the T. fim- 

 briata of Lamarck, in which opinion a re-perusal of the description, 

 in the Fauna Groenlandica, does not induce me to coincide. 



Our species is without any doubt the same as the Idmonea trans- 

 versa of Milne-Edwards, but it cannot, in our opinion, be separated 

 generically from T. phalangea and flabellaris. Indeed monstrous 

 specimens are sometimes met with which can with certainty be re- 

 ferred to neither of these species, except by reference to specimens 

 of a more normal character on the same site. 



I have seen small specimens on crabs and shells which correspond 

 exactly with the figure of Lamouroux's Obelia tubulifera, which I 

 consider to be Tub. serpens in an early state of existence, evolving 

 itself on the flat and even surface of a bivalve shell. 



9. T. HYALiNA, " encrusting^ semi-transparent, memhrano-cal- 

 careous ; cells distant from each other, tubular, erect, arranged 

 in one or two circular rows round a plain centre ; apertures 

 unarmed and frosted.'''' R. Q, Couch. 



Tubulipora hyalina, Couch Zooph. Cornw. 47 : Corn. Faun. iii. 108. 



Hah. — " On Fucus palmatus, rare. Polperro," B. Q. Couch. 



" Encrusting in small semi- transparent patches of about the 

 diameter of a pea. The cells are distant, erect, arranged in one or 

 two rows round a plain centre ; occasionally there are a few cells 

 irregularly arranged in a circumscribed patch in the centre, but 

 separated from the external rings by a plain surface. The apertures 

 are even, unarmed, with frosted rims." B. Q. Couch. 



2. DiASTOPORA,* Lamouroux. 



Character. — Polypidom calcareous, encrusting, undefined; 

 the cells alternating, tubular, horizontal, immersed, with a 

 raised circular aperture. 



* As defined by us, the genus corresponds with the " Les Diastopores simples" of 

 Milne-Edwards. Mem. p. 39. — The name appears to signify "having pores at 

 intervals," from Sidarfijia an interval, and wopog a passage. 



