Retrospective Criticism. "765 



mud of the Thames, from which it is built up by a wall of 

 bricks, near to which wall the walk is skirted by a row of trees, 

 whose branches hang partly over the river. When I passed 

 by, the tide was down, and the mud left bare to the breadth 

 of five or ten yards, on which the animals in question so 

 abounded as to give the mud quite a reddened hue. Al- 

 though rain was not then falling, drops of water were dripping 

 from the arch-spread arms of the trees above, and, as these 

 drops struck the mud beneath, the red tentacula were with- 

 drawn from circular patches of from 12 to 18 in. wide, but as 

 soon as the jar had subsided, a minute or so afterwards, they 

 were again exserted. As the falling drops were not few, and 

 fell on the mud in various and ever-varying places, a very in- 

 teresting and pleasing changement in the degree of redness 

 was observable, 



** The checker'd earth seem'd restless as a flood 

 Brush'd by the wind, " 



as a poet, not curbing his imagination, might say. — J. D, 



Pdj^is quadrifblia aiid its Variations, (p. 429.) — I have been 

 much pleased with Professor Henslow's ingenious remarks 

 on this favourite plant (p. 429.), and feel obliged to him for his 

 theory connecting the genera Paris and Trillium which have 

 so singular a numerical character in their leaves and fructifi- 

 cation. It gives me pleasure to be able to add one more to 

 his thirty-eight varieties, viz., one with eight leaves and four 

 sepals, petals, and stigmas. It was found in Cotterill Clough, 

 Cheshire, the only locality for Paris within twelve miles of 

 Manchester. I frequently meet with it with five leaves, less 

 frequently with three, and, in the latter case, almost invariably 

 without inflorescence. Some young friends of mine trans- 

 planted a few roots, but had the mortification to find that the 

 flowering stems degenerated into the barren trifoliate variety. 

 Indeed, I have remarked that the latter is always smaller than 

 the other varieties, and apparently the shoot of a younger 

 plant. — William Thomson. Manchester, June 14. 1832. 



Paris quadrifblia, a Fault in the Figure of. (p. 430. fig. 86. a.) 

 — The stamens are represented exactly like the stigmas, while 

 in nature they are quite dissimilar : this was my fault, in not 

 sending you a drawing to copy from. — J.S.Henslow. June 14. 

 1832. 



Do the Leaves of the Round-leaved Sundew {Drosera rotun- 

 difblia L.) possess Irritability ? (p. 491.) —Without any claim 

 to the degree of acquaintance with the habits of the round- 

 leaved sundew ascribed to me by J. D. (p. 492.), I may yet, 

 without too great presumption, so far accept his challenge as 

 to express it as my opinion, made with all deference to that 



3 c 2 



