1904 - 5 .] Report on Medusae found in Firth of Clyde. 743 
(b) Visitors to the Clyde . 
Ectopleura dumortieri . (?) 
Gemmaria implexa. (?) 
Ilippocrene pyramidata. 
Lizzia blondina. 
Sarsia gemmifera. 
Irene pellucida. 
Mitrocomella polydiademata. 
Octorchis gegenbauri. 
Saphenia mirabilis. 
Rhizostoma octopus. 
Dipleurosoma typicum. 
Comparison of the Hydromedus^i of the Clyde with those 
found in Valencia Harbour and at Plymouth. 
All the Hydromedusse found in the Clyde have been taken in 
Valencia harbour, with the exception of the following species, — 
Sarsia eximia , Thamnitis, sp., Irene pellucida , Mitrocomella 
polydiademata. 
In Valencia harbour about 20 species of Hydromedusse have 
been taken, which have not yet been seen in the Clyde. 
All the Hydromedusse found in the Clyde have been taken at 
Plymouth, with the exception of the following species, — 
Ilippocrene pyramidata , Thamnitis , sp., Dipleurosoma typicum , 
Melicertidium octocostatum , Mitrocomella polydiademata. At 
Plymouth about 15 species occur which have not yet been seen 
in the Clyde. 
The Scarceness of Hydromedusse during 1901-1902 in 
the Clyde. 
The result of tow-netting during the eighteen months has brought 
together a fair list of species, but I wish to draw attention to the 
scarcity of the Hydromedusse during this period. For the six 
months of 1901 only three species are recorded (Table I.) as being 
abundant or very abundant ; namely, — 
Hybocodon prolifer, in Loch Eanza on May 8th. 
Obelia nigra , off Little Cumbrae on June 6th. 
Lizzia blondina , off Little Cumbrae and Millport on July 18th 
and 20th. 
