2 PEOCEEDIXGS OF THE 



present, Mr. AV. Percy Sladen exhibited two microscopic prepa- 

 rations of the anibulacral ampullse of Echini, showing that each 

 ampulla is supplied by one offshoot from the main ambulacra! 

 water-vessel. (See Appendix, p. 30.) 



Mr. Hartiug exhibited a specimen of the Baltimore Oriole 

 {Icterus Baltimore), Avhich had been lately obtained, at Balta 

 Sound, Shetland, but which he regarded as an escaped cage-bird. 



The following paper was read : — 



" A Contribution to the Study of the Eelative Effects of dif- 

 ferent parts of the Solar Spectrum on the Assimilation of Plants." 

 By the Eev. Prof. Henslow, M.A., E.L.S. 



November 20th, 1890. 



Prof Charles Stewart, President, in the Chair. 



The Minutes of the last Meeting were read and confirmed. 



Joao Erancisco Braga, Esq., and the Eev. Edmund M'^Clure 

 were elected Eellows. 



Mr. Greorge INIurray exhibited specimens of a freshwater 

 Delesseria (D. amhoinensis) previously unknown. 



On behalf of Mr. Henry Hutton, of Cape Town, Mr. B. 

 Day don Jackson exhibited some follicles and seeds of a somewhat 

 rare Asclepiad {Dregia floribunda) ; and showed also, on behalf 

 of Mr. W. Matchwick, some ripened fruits of Ailantlius glan- 

 dulosa from a tree at Eeigate, said to be 100 years old. 



Prof. E. 0. Bower exhibited several drawings of microscopic 

 sections of Carboniferous Eern sporangia, belonging to Prof. 

 "Williamson, and pointed out the peculiarities of their structure 

 and the singular uniformity of type which they exhibited. Eor 

 comparison with them he also showed sections of the sporangia 

 of Todea larhara ; and while hesitating to refer them to any 

 distinct genus, he thought that their Osmuudaceous affinity was 

 unmistakable. 



Mr. J. E. Harting exhibited some original MSS. and water- 

 colour sketches of birds, fishes, and plants found in Sussex by 

 William Markwick, the friend and correspondent of Eev. Grilbert 

 "White, of Selborne, w^hich had been presented by him to the 

 Society in, his lifetime, and had been lost sight of for many 

 years. The drawings were sufficiently well executed to enable 

 the correct determination of several species which the author 

 had failed to identify. 



