FAUNA OF THE ISLES OF SCILLY. 



121 



On this visit I particularly noticed the advantages of the New 

 Grimsby channel, between Tresco and Bryher, for tow-netting. 

 It IS a sheltered spot and suitable for working in a small rowing 

 boat. The tide flows with sufficient force to keep a net extended 

 from a boat at anchor. This channel can be reached in a few 

 minutes from the little harbour on Tresco. 



During this short visit the sea was calm and the weather 

 very fine and warm. A silk net was used having a mesh of half 

 a millimetre. No attempt was made to record all the animals 

 caught in the net. A complete list of the Medusa) is given, and 

 the names of a few other animals which happened to be known 

 to me. 



INFUSORIA. 



Noetiluca miliar is. This protozoon was verj^ abundant. A great 

 shoal existed, forming one of the characteristic features of 

 the plankton. JSoctiluca occurs at times in such vast numbers 

 as to discolour the sea. It would be interesting to know 

 if such shoals are only formed during a long period of very 

 tine weather when the sea becomes calm and high in tem- 

 perature. 



Ceratium tripos. Common, but the mesh of the net was not tine 

 enough to catch any quantity. 



HYDROMEDUS^. 



ANTHOMEDUSyE. 



Amphinema dinema (Perou et 

 Lesueur). Fairly com- 

 mon. Mostly adult speci- 

 mens with ripe gonads. 



Amphineim. sp ? One specimen 



Corymorpha nutans, Sars. Few 

 specimens. 



Bipurena haltcrata (Forbes). 

 One adult specimen. 



Euphysa aurata., Forbes. Very 

 scarce. 



Gemmaria implexa (Alder). 

 Fairly common. Some 

 early stages, but mostly 

 adults with ripe gonads. 



Larsabellarum, Gosse. Scarce. 

 Only early stages were 

 found. 



Lizzia bJondina, Forbes. 



Fairly common. 

 Margelis autumnal is (Hartlaub). 



Few adults. 

 Sarsia f/emmifera, Forbes. 



One specimen. 

 Tiara pileata (Forskal). One 



specimen of an early 



stas:e. 



