34 MARINE FAUNA OF ST. ANDREWS. 



Class CTENOPHOE^. 

 Two representatives only are found at St. Andrews, viz. a 

 species of Beroid and a Pleurobrachia. The former occurs in 

 vast swarms in July, indeed almost as plentifully as in the 

 Zetlandic seas, and is easily procured by the hand-net from 

 the rocks or at sea. The latter is equally abundant from 

 August to the end of autumn, and even in winter, occasionally 

 filHng the towing-net or the dredge in the bay, and thrown 

 ashore after storms on the West Sands. Few objects are more 

 engaging than one of these spherical jellies in a clear glass 

 vessel of sufficient size to exiiibit the matchless mechanism of 

 of its complex tentacles and the splendid iridescence of its 

 locomotive rows. 



Order Saccate, Agassiz. 

 Genus Pleurobrachia, Flem. 

 Pleurobrachia pileus, Eschsch. 

 Abundant. It eagerly devours Carcinus maenas in the 

 zoea-stage. 



R.M. N\ 



Plearohrachia piletts, swimming downwards after engulfing a zoea. 



Order Beroid^, Ggbr. 

 Genus Idyia, Freminville, 

 Idyia cucumis, O. Fabr. 

 Occasionally in large numbers in July and August. 



