The Scottish Naturalist. 57 



Again, we have around us changes going on of the highest 

 interest, whether we regard them from a zoological or geological 

 point of view. The clays of Dryleys, Pugiston, and Redfield are 

 little removed from the human period, and the shells, star fishes, 

 and other animal-remains found in them are of species living now 

 in the Greenland Seas ; while the estuary clays, which surround the 

 South Esk Basin, and form the " clay half" of the town, as well as 

 the old sea margins of the sand hills, and on Rossie Island, contain 

 shell deposits of species still living on our shores. The Links and 

 the Bents teach us how, without any convulsion or upheaval, the 

 land has gained gradually, and is now gaining from the sea ; just as 

 the rent rocks and sea-worn caves to the north and south tell us, 

 on the other hand, how the sea has gained from the land. 



The zoology and botany of the estuary of the South Esk Basin 

 have an interest all their own. We there find species surviving 

 that are apparently tending to become extinct. Zostera marina still 

 lingers, as doalso the mollusca Scrobiculariapiperataand Conovulus 

 ridenta ; while several species of Rissoa, and the curious crus- 

 tacean, Corophium longicorne abound in millions in the mud, to the 

 delectation of the Red-shank and other wading birds, which are 

 attracted thither by the dainty fare. Just beyond the tide mark in 

 the South Esk we meet with the Unio or pearl mussel, while in its 

 tributary, the Pow, we find instead the Anodonta or swan Anodon, 

 the largest British fresh-water bivalve. 



The investigation of the entomology of the the sea-shore within a 

 walkable distance of Montrose would, I am certain, yield valuable 

 results ; while the area within the tide mark abounds with rare and 

 interesting marine animals, whose structure and habits are well 

 worth studying either in their native haunts or in the aquarium. We 

 should also seek to enlist the interest of the fishermen and steam- 

 trawlers in our researches ■ a bucket or old tub can be used as a 

 receptacle for the rejected rubbish or " vermin " as the fishermen 

 term everything but edible fish, and which, though to them useless, 

 are treasures from the deep for the naturalists. 



Then we have pre-historic man to look after in his caves, kjokken- 

 moddings, standing-stones, and burial-mounds. We have to 

 gather up his stone implements and pottery, and try to dovetail 

 him, on the one hand with the post-glacial period, and on the other 

 hancLwith the early historic time. W T e have to discover the how 

 and the wherefore of these wonderful vitrified forts, such as that at 



