SEA-NETTLES. 107 



found by EHRENBERG in the Red Sea, and he could not discover 

 any difference between it and that found in the northern and the 

 Baltic seas. Oftentimes many species of Medusae are collected in 

 such quantities at certain places, that they form as it were banks 

 in the sea, which it requires days to sail through 1 . In fine calm 

 weather Medusae come to the surface : during storms they seek the 

 quieter waters of the depths. 



1 PERON d LESUEUE Annales du Mus. xiv. p. 222 ; such a bank of Medusa aurita, 

 in the Baltic at the mouth of the Weichsel was also described by V. SIEBOLD, Beitr. z, 

 Naturgesch. der wirbellosen Thiere, s. 5. 



