A HISTORY OF KENT 



coast of Kent are much more limited than on the other side of the 

 estuary, but, as far as they go, they show that in summer the density 

 off Ramsgate is about the same as in the North Sea off Lowestoft, and 

 at the Nore about the same as in the Swin, being less than in the Wallet 

 along the coast of Essex, probably because there is a much larger area 

 of shallow water than along the coast of Kent exposed to evaporation in 

 summer. Possibly this is one reason amongst several others why the 

 animals differ materially. 



The Swale at and above Queenborough is really a strait and not an 

 estuary, and at Queenborough there is only a small difference between 

 the density of high and low water, which plays such an important part 

 in some estuaries. There is only a small decrease in that part ot the 

 Swale near Milton Creek, which is farthest removed from the two 

 openings into the sea. These facts probably explain why, on the 

 whole, the animals found in the Swale differ considerably from those 

 met with in the estuaries of Essex and Suffolk. 



The Medway up to and beyond Chatham, the Stour up to and 

 beyond Sandwich, and the Thames up to and beyond Erith, are 

 examples of the opposite extreme, the water being in some places 

 almost as salt as the sea when the tide is high, and almost fresh when it 

 is low. These facts have, of course, an immense influence on the 

 distribution of the animals along the north coast of Kent. 



The Swale near Queenborough. 



I have dredged and otherwise studied the Swale from its junction 

 with the Medway right up to Milton Creek. One thing which struck 

 me much was the great difference in the number and species of the 

 animals met with in different years. For example, on one occasion I 

 found the bottom almost covered with an enormous number of small 

 mussels, and there were few starfish. The next year these seemed to 

 have invaded the district, and almost or entirely cleared the ground of 

 mussels. One year the beautiful medusa, Chrysaora isosceles (Linn.), 

 was very common, but in other years almost or quite absent. In one 

 year I saw off the Nore more large individuals of Rhizostotna octopus 

 (Linn.) than I ever saw there or anywhere else. The other Medusa? 

 seen more or less frequently were Aurelia aurita (Linn.) and Cyanea 

 captllata (Linn.). Pleurobrachia pileus (Modeer) was common. An 

 unidentified Beroe was also found. The number of Noctiluca mUiaris 

 was sometimes very great. In July 1883 the average number from top 

 to bottom of the water was about 750 per gallon, and occasionally many 

 more. 



Before it was burned down I used to find on the old pier many 

 specimens of the white, the flesh coloured and the dark brown varieties 

 of Act'moloba dianthus (Ellis), Sabella pavonia (Sav.), and a nemertian 

 worm, probably Serpejitaria fiisca (B.M. Cat. of Worms) which could 

 extend itself in a remarkable manner. From the mud banks I obtained 

 Nereis diver sicolor (Miiller) ; but by far the most interesting polychste 



92 



