THE SHORES OF BRITAIN. 39 



by the mighty force of the tide which has been 

 driven in, in thunder, by the power of a fierce 

 tempest, as when the waves have rolled gently and 

 calmly to the shore in their sweetest murmurs. 

 These insects have never been seen to swim, in- 

 variably walking among the branches or leaves of 

 the confervce or fiici, amongst which they delight 

 to dwell ; and when shook out from their hiding- 

 places into a bottle or tumbler of water, they may 

 be seen to fall in gyrations to the bottom, without 

 ever attempting to dart through the watery element, 

 as in the case with the Cyprides. Upon reaching 

 the bottom they open their shells, and creep along 

 the surface of the glass ; but when touched or 

 shaken, they immediately again withdraw themselves 

 within their shell, and remain motionless."* The 

 Cyprides, here alluded to in comparison, are species 

 very closely resembling these, inhabiting abundantly 

 every stagnant ditch and pool of fresh water. They 

 have their antennas and feet beautifully feathered 

 with long fringed bristles, by aid of which they 

 swim with much vivacity. In exactly similar situ- 

 ations to those above described are found other 

 Entomostraca, marine species of the genus Cyclops, 

 almost equally minute, and equally interesting. 

 Like their kindred of the same genus found in fresh 

 waters, and which are so numerous in the water 

 conveyed into London that we swallow them daily, 

 these swim with ease, progressing by sudden bounds 

 made with great vigour and effect. Mr. Baird no- 

 tices of one marine species (C. depresses), which he 



* Mag. Zool. and Bot. ii. 141. 



