1904 - 5 .] Report on Medusae found in Firth of Clyde. 
741 
Thaumantias octona, Forbes. [Phialidium cymbaloideum .] 
Tarbert, Loch Fyne. Forbes. 
Arran. Haeckel. 
Thaumantias thompsoni, Forbes. [ Phialidium temporarium . ] 
Lamlash Bay. Herdman. 
SC YPHOMEDU SJE. 
[Aurelia aurita. 
[Cyanea capillata . ] 
[Depastrum cyathiforme . 
Aurelia aurita , Linn. 
(In the “ Fauna of the 
Clyde.”) 
Cyanea capillata (Baster). 
Lamlash Bay. Herdman. 
Lucernaria cyathiformis, Sars. 
Arran. Landsborough. 
Russell. 
Cumbraes. Russell. 
Lucernaria fascicularis, Fleming. [Lucernaria quadricornis. 
Ardrossan. Alder. 
Rhizostoma pulmo. 
(In the “ Fauna of the 
Clyde.”) 
[Rhizostoma octopus. 
Medusae and their Hydroids. 
The medusae found in the Clyde include 17 species of Antho- 
medusae, 12 species of Leptomedusae, and 5 species of Scyphomedusae. 
There are altogether 30 species of Anthomedusae and Leptomedusae, 
belonging to about 25 genera, for which there should be a 
corresponding number of hydroid genera. 
There are 77 species of Hydroids given in the compiled list of 
Hydroida in the “Fauna of the Clyde.” Out of these only 10 
species, belonging to 6 genera, are known to liberate medusae. 
At Plymouth the proportion of non-medusa-budding hydroids to 
medusa-budding hydroids is very nearly the same as that in the 
Clyde. It therefore follows that either many of the Antho- 
medusae and Leptomedusae have a direct development, or that 
many more hydroids have yet to be discovered. My own 
observations tend to show that the hydroids have yet to be found. 
