276 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



in Port Erin Bay in August, 1885. This species has been 

 recorded in nearly every list of British medusae. Up to 

 this time I have not met with a single living specimen of 

 this common medusa. Every specimen taken, which 

 has any resemblance to description and figure of this 

 species, possesses marginal vesicles between the tentacles. 

 Hseckel has placed T. hemisphaerica, Miiller, among the 

 Thaumantidse, a family which is characterised by the 

 absence of marginal vesicles between the tentacles. 



I may here say that specimens preserved in spirit are 

 not to be relied upon for the absence of marginal vesicles. 

 The otolith usually disappears and the vesicle shrivels up. 



Forbes obtained specimens of T. punctata off the Isle 

 of Man in June, 1839. Hseckel considers this species to 

 be a form of T. hemisphaerica. 



Laodice cruciata, L. Agassiz (15). 



Thaumantias pilosella, Forbes (9). 



Garner (10) found this species abundantly in Douglas 

 Bay. 



Laodice cruciata is recorded by me in the Seventh 

 Annual Report (1893) of the L.M.B.C. amongst the species 

 taken at Port Erin. I regret to say this is an error on 

 my part, as the specimens have since been identified as 

 Mitrocomella polydiadema. 



This species is widely distributed, Naples and other 

 places in the Mediterranean, Holland, Shetland, St. 

 Andrews, Plymouth, Falmouth. 



Laodice calcarata, L. Agassiz {2). 



Lafoea calcarata, (A. Agassiz I). 



On May 5th, 1894, I took in Port Erin Bay a single 

 specimen of a medusa which I believe to be an early stage 

 of Laodice calcarata^ an American medusa which so far 



