PROCEEDINGS OF SOCIETIES. 



Dublin Miceoscopical Club. 

 2^th October, 1875. 



Acetta coriacea from Oban Bay, new to the British Seas, in its 

 simplest form. — Dr. A. Macalister presented a specimen of 

 Acetta coriacea from Oban Bay, showing the simplest form of that 

 species. The " personse " were separate, each with a single 

 " mouth." Hitherto the only recorded forms of this comimon 

 sponge from the west coast were examples of the Aulophlegma- 

 type, and Dr. Macalister believed this to be the first specimen of 

 the simple form of this species recorded from the British seas. 



Lejeunia microscopica, Taylor, exhibited. — Dr. D. Moore showed 

 the rare and pretty Lejeunia microscopica, Taylor, which he had 

 just brought from the west of Ireland ; although to the naked 

 eye little in the shape of an organized plant makes itself evi- 

 dent, this little gem, probably the very smallest of our higher 

 Cryptogams, forms a very pretty object under a \" objective. 



Germinating Seedlings of Drosera. — Dr. Moore likewise drew 

 attention to some germinating seedlings of Drosera ; these had 

 two ovate, smooth, cotyledonary leaves, the third leaf in all assum- 

 ing the spathulate form of those of the species, and was clothed 

 with the pretty characteristic insect-capturing glandular hairs. 



Navicula StoJcesiana,-a.B.,0''M.e2irdi. — Kev. E. O'Meara presented 

 what he considered to be a new form of Navicula, of which the 

 following is a description: — Valve large, rhombic-lanceolate, 

 length "0045", breadth 0018 " ; marginal striate band wide, inner 

 striate band contiguous to the median line, narrow, and appearing 

 to be elevated above the general surface, free space included 

 within the inner margins of the inner striate bands narrow-linear, 

 forming in the middle a very narrow stauriform line ; space inter- 

 mediate between the inner and outer striate bands occupied by 

 lines of striae which seem to be prolongations of the striae of the 

 outer striate band ; striae close, punctate, radiate. This form in 

 most respects is similar to Nav. irrorata, Schmidt, 'Atlas der Diat.,' 

 t. ii, f . 14 ; but it seems distinguished by the fact of having the 

 intermediate space striate, whilst in Nav. irrorata this portion of 

 the valve is represented as unstriate. Mr. O'Meara proposed under 

 the name of Navicula Stokesiana to identify this beautiful and 

 rare form with the name of the present respected President of 

 the Royal Irish Academy. 



Fenium curtum, Breb., exhibited. — On the part of Mr. Crowe 



