8 BRITISH COPEPODA. 



more especially of the flat-bodied Porcellidiince and 

 their allies, which appear to find shelter in the 

 numerous inequalities of its rugose fronds. Amongst 

 the groves of smaller algse with which tidal rock-pools 

 are often so densely overgrown, Copepoda are always 

 to be found in abundance, but though I have paid 

 particular attention to the matter I have not found 

 that the different species have any particular prefer- 

 ences as to the kinds of weeds which they haunt ; it is 

 probable that shelter rather than food is the reason of 

 their liking for these marine forests. The brackish 

 water of salt marshes and small estuaries sustains a 

 peculiar Bntomostracan fauna, the most characteristic 

 members of which, amongst the Copepoda, are Temora 

 velox, Lilljeborg, Tachidius brevicornis, Miiller, and, 

 less commonly, Cyclops insignis, Glaus, Nannopus 

 palustris, Brady, Platychelipus littoralis, Brady, Meso- 

 chra Lilljeborgii, Boeck, and Delavaliapalustris, Brady; 

 with these there is usually associated a peculiar group 

 of Ostracoda, Cythere castanea, Sars, Cytheridea 

 torosa, Jones, Loxoconcha elliptica, Brady. The Mala- 

 costraca, Foraminifera, and other branches of the 

 fauna of such localities present likewise features of 

 great interest, but it is impossible here to enter fully 

 into the consideration of the subject ; the reader who 

 desires further information is referred to the papers 

 mentioned below.* Pools of sea water above, or at 



* ' On the Crustacean Fauna of the Salt Marshes of Northumberland 

 and Durham," by G. S. Brady, C.M.Z.S. ('Natural History Trans- 

 actions of Northumberland and Durham,' vol. iii). " On the Ostracoda 

 and Foraminifera of Tidal Rivers," by G. S. Brady, C.M.Z.S., 

 David Robertson, F.G.S., and H. B. Brady, F.L.S. ('Annals and 

 Magazine of Natural History,' ser. 4, vol vi, .1870). " On the Zoology of 



