314 PROCEEDINGS OF SOCIETIES. 



material resembling the structures to which he bad given the 

 name of 'foraminated ring' ('TraDs. E.I. A.,' vol. xxv, PI. 16), 

 and which is characteristic of the spines of the Diademitida) 

 to which those of Amblypnestes thus come to bear a strong 

 resemblance. 



Schistostega Osmundacea, exhibited. — Dr. Moore showed an ex- 

 ample of the pretty " Cavern Moss " Schistostega Osmundacea, 

 which he had lately brought from Todmorden. It is well known 

 that this plant has the property of partly illuminating the gloomy 

 recesses where it loves to dwell. It forms a pretty and a botani- 

 cally interesting object. 



Diatoms from Arctic Seas, exhibited. — Rev. E.O'Meara presented 

 for inspection a slide containing Diatomaceous forms from a 

 gathering made in the Arctic regions by Dr. Moss of II. M.S. 

 ' Alert.' It was collected from a heap of stuff thrown by the 

 tide upon the beach. GTreat interest is attached to this collection 

 from the fact of its having been made so far north as lat. 82° 23'. 

 Many species common in our own country were met with, e.g. 

 Navicula Do7ikinii, N. cyprinus, N. Cleveana, Surirella striatula, 

 Paraliamarina, Actijioptychus senarius,&c. Several forms occurred 

 which hitherto have been met with only in the Arctic regions, e.g. 

 Thallassiosira Nordenskioldii Cleve, Achnanthes Arctica, Cleve, 

 Grammatophora Arctica, Cleve, Amphora lanceolata, Cleve, 

 Synedra Kamskatica, O'M. 



Arctic Dust, which contained a Nostochaceous Organism. — Dr. 

 Moss showed some Arctic Dust containing some organic traces,but 

 the only thing abundant was a Nostoc-like organism, generally of 

 a brownish-red colour, yet few, if any, of the examples showed the 

 cells in chains or chaplets, nor any heterocysts ; they were rather 

 clustered without any order ; Mr. Archer felt, therefore, rather 

 disposed to refer the form to Gloeocapsa. 



^eu) Species of Closterium, shoivn. — Mr. Archer showed ex- 

 amples of what would seem to be a new species of Closterium, 

 coming nearest to CI. costatum, in that it was of a similar contour 

 and curvature, but it was larger, and, whilst the striae were very 

 like near the similar-looking apices, they speedily got lost, and 

 for from four fifths to three fourths of the extent of the cell they 

 were absent. Unlike other Closteria, then, which are all either 

 equally striate throughout or smooth, we have here to do with a 

 form only partially striate. Mr. Archer would call this form 

 Closterium mediolcere ; he exhibited examples of Closterium cos- 

 tatum side by side for sake of comparison. 



