2 PROCEEDINGS OF THE 



greetings be so welcome to me, because of the esteem and afEection 

 I feel for the Society as one of its oldest members and because of 

 my descent, as grandson and son of two of its earliest. 



Eequesting you to make known to my fellow-members my 

 lioarty appreciation of their affectionate congratulation and my 

 own best wishes for the continuatiou of its increasing prosperity, 



Believe me, sincerely yours, 



(Signed) Jos. D. Hookee. 

 The President, 

 Linn can Society. 



Dr. A. B. Rexdle, V.-P., having taken the Chair: — 



Dr. D. H. Scott gave an account of the Palaeozoic Fern, 

 Zijgopteris Grayi ("Williamson). (Subsequently published in the 

 ' Annals of Botany,' vol. xxvi. no. ci, 1912, pp. 139-67, 5 pis.. 



Dr. Rendle having spoken on the subject of the paper, left the 

 Chair, and the President resumed. 



A paper, by Miss Edith E. Bamford, entitled "Pelagic Actinian 

 Larvae," and communicated by Prof. J. Stanley Gardiner, F.R.S., 

 E.L.S., was read in abstract. 



Mr. Alfred 0. Walker contributed a paper on " The Distri- 

 bution of Elodea canadensis, Michx., in the British Isles in 1909." 

 (Abstract, p. 71.) 



A discussion followed, in which the following took part : — 

 Mr. James Groves, Mr. E. M. Holmes, the Rev. T. R. R. Stebbing, 

 Prof. J. W. H. Trail, Dr. Margaret Benson, Mr. II. N. Dixon, 

 Mr. J. C. Sheustone, Prof. A. Dendy, Dr. O. Stapf, Mr. Henry 

 Groves, Dr. A. B. Rendle, and the President. 



Dr. James Murie exhibited sets of specimens of the " Slipper 

 Limpet" {Crepidula fornicata), the shells themselves in gra- 

 duated series and living examples attached to oysters, mussels, tfec. 

 These were obtained in the Essex waters, by dredging, and from 

 shallow muddy shore tracts. 



The "Limpets" have now become a nuisance on the oyster-beds 

 of Kent and Essex. Originally they were introduced from America, 

 among the barrelled oysters brought over for relaying. They have 

 since become thorougldy naturalised, and on the Blackweter and 

 River Crouch are dredged up in tons, attached to the oysters, 

 mussels, &c. 



Unlike the Starfish, devourers and arch-enemies of the oyster, 

 the Mussels, which literally smother them, or the Whelk Tingles, 

 which bore through their shells, the " Slipper Limpet " is more of 

 a commensal parasite and messmate, partaking of the oyster's 

 food. 



The labour and expense involved in constant dredging for them 



