87% Prof. Allman on the Construction and 



Campanularia Johnstoni, Alder (sp.), = Campanularia volu- 

 hilis, ]o\\n%i.,-=Clytia Johnstoni, Agass. 



Campanularia noliformis, M'Crady (sp.), = Clytia noliformis, 

 Agass. 



Campanularia cylindrica, Agass. {si^. ),=: Platypyxis cylindrica, 

 Agass. 



Campanularia Gegenbaurii, Sars. 



Campanularia dichotoma, Kolliker. 



The following species are placed provisionally in this genus, 

 the gonophores not having yet been observed in any of them. 

 Further research will doubtless cause their distribution among 

 two or more genera : — 



Campanularia voluhilisy Linn. 



Campanularia verticillata, Linn. 



Campanularia Hincksii, Alder. 



Campanularia integra, Macgillivray. 



Campanularia raridentata^, Alder. 



Campanularia breviscyphia, Sars. 



Campanularia bicophora, Agass. {s^.),=i Clytia bicophora,Ag3iSs. 



2. Obelia, Peron & Lesueur. 



Trophosome. — Hydrocaulus branching, rooted by a creeping 

 filiform hydrorhiza ; hydrothecse bell-shaped, with an entire or 

 serrated margin, and destitute of operculum; tentacula sur- 

 rounding the base of a very contractile, conical, clavate, or 

 trumpet-shaped metastome. 



Gonosome. — Gonangia developed from the hydrocaulus, and 

 containing phauerocodonic gonophores. Medusse very flat, so 

 as to approach the form of a disc, with a short four-lipped ma- 

 nubrium ; radiating canals four ; marginal tentacles numerous, 

 with their roots prolonged in the form of short csecal continua- 

 tions into the walls of the umbrella ; lithocysts two in each inter- 

 radial space, each lithocyst placed upon the base of a tentacle at 

 its inner side. 



The changes undergone by the Medusa in its progress towards 

 maturity consist chiefly in an increase in the number of mar- 

 ginal tentacula. 



Obelia dichotoma, Linn, (sp.), = Laomedea dichotoma, var. a, 

 J ohrxst.,— Campanularia gelatinosa. Van Ben. 



Obelia geniculata, Linn, (sp.), = Laomedea geniculata, Johnst. 



Obelia commissuralis, M'Crady. 



Obelia diaphana, Agass. (sp.), r=zEucope diaphana, Agass. 



* Judging from an observation of Wright (Mic. Journ. n. s. vol. ii.), 

 it is quite possible that the Campanularia raridentata of Alder may belong 

 to the genus Thauntbntias. See below p. 377« 



