102 PROCEEDINGS OF SOCIETIES. 
Cidogonium excisum, Wittrock et Lundell, new to Britain.— Mr. 
Archer exhibited (from Connemara), new to Britain, fertile examples 
of Gidogonium excisum, Wittrock et Lundell, a very minute species, 
but one so distinctly marked there could be no doubt as to its 
identity. He showed Wittrock’s graphic figure, along with his 
excellent description, distinctly fixing the species. It may be 
possibly more common that might be @ priorz supposed from but a 
single Swedish, afterwards a single Austrian, and now a single Irish 
locality being recorded, but, of course, if met with in the sterile 
condition only, the identity could not be certain, and it must then, 
almost inevitably, be overlooked. 
23rd July, 1874. 
Constituents of Leinster Granite—Professor Hull exhibited 
sections of Leinster granite from Killiney, showing, when viewed 
under polarized light, that two felspars are present, a monoclinic. 
and a triclinic, besides the quartz and mica. Judging from the 
analysis of the granite made by Professors Haughton and Gal- 
braith, which in all cases showed the presence of soda, Mr. Hull 
concluded that the triclinic felspar must be albite. This mineral 
had only once been previously detected, viz. by Dr. Westropp in 
a specimen at Kingstown, but, judging by the sliced specimens 
from several localities, Mr. Hull concluded that albite was always 
present in the granite in small proportion and was an essential 
constituent of it. 
Navicula Heufleri, Grunow, N. hungarica and N. fulva, 
Nitzsch, exhibited—Rev. E. O’ Meara exhibited examples of the 
foregoing. The last, as Donkin properly observes, strongly 
resembles WV. cuspidata, but is distinguished from it by the cha- 
racter of the strie, which are oblique in the former, whilst in the 
latter they are parallel. All these forms were found in a gather- 
ing made by Rev. M. H. Close at Lough Gill, Co. Kerry. 
Muscular Wall of Intestine of Mouse-—Mr. B. Wills Richardson 
exhibited a slide containing a preparation in glycerine of the 
muscular wall of the intestine of the mouse. A _ portion of 
the intestine was immersed for several days in Beale’s carmine 
fluid and glycerine; potash, however, having been substituted 
for the ammonia. With a moderate-sized sable brush he was 
then able to pencil the muscular wall off the mucous wall of 
the bowel. Pieces of both walls were then mounted as permanent 
preparations. A mounting of the mucous wall he had exhibited 
at a previous meeting of the Club. As potash had a tendency to 
soften many structures, they must not be allowed to remain too 
long in it lest they should be spoiled. Mr. Harry Draper substi- 
tuted the potash for him (Mr. Richardson), as it has little, if any, 
tendency to destroy nitrate of silver stain. 
Actinophrys digitata, Dujardin (?), exhibited —Mr. Archer 
showed some examples of the rhizopodous form, most probably 
Actinophrys digitata, Dujardin, both in the natural condition 
