174 PROCEEDINGS OF SOCIETIES. 
Amongst the Difflugian (Lobose) forms which here presented 
themselves was that exceedingly well-marked and withal very 
pretty species Difflugia triangulata (Lang). The figure given by 
Mr. M. H. Lang (‘ Quart. Journal of Microscopical Science,’ No. 
XX, October 1865, p. 285) is abundantly graphic, in order to 
recognise the animal at a glance. 
Mr. Archer likewise showed some other interesting forms be- 
longing to the Radiolaria in Carpenter’s sense, one altogether new, 
and besides which several others seemingly more or less uncom- 
mon, or, at least, for the first time recorded. as Irish, were pre- 
sented. In this rich gathering those which seemed to be common 
were Huglypha alveolata, Actinophrys sol, and A. Eichhornii, of 
which latter there was on the table a fine specimen which had 
engulphed three Stentors, proportionately not very moderate mor- 
sels. Of those not before recorded in Ireland, although possibly 
not uncommon in suitable localities, there were several distinct 
and well-marked forms. Two of these were Trinema acinus 
(Dujardin), and Cyphoderia margaritacea (Schlumberger). 
One of those now exhibited seems to be absolutely new; it 
appears to find, however, its closest affinity in the genus Pseudo- 
difflugia (Schlumberger) ; specimens of forms seemingly referable 
to the latter genus, as time did not now permit, Mr. Archer 
hoped to be able to present at the next meeting of the Club. 
Of the new form he hoped that a figure would shortly appear 
in the ‘Microscopical Journal ;’ hence it would be unnecessary 
to give any details here. 
This new form, however, seems to be distinguished from every 
freshwater rhizopod by having at each opposite extremity of the 
test a distinct rather wide aperture, furnished with a short, well- 
marked neck. From each of these opposite apertures there issues 
a dense compact tuft of slender filiform occasionally branched 
pseudopodia. For this genus Mr. Archer would propose the name 
Amphitrema. 
Dr. E. Perceval Wright regarded the exhibition that evening 
by Mr. Archer of so many forms of fresh-water Rhizopods as one 
of great interest. He had had abundant opportunity of examin- 
ing many specimens of the form, for which Mr. Archer had very 
properly constituted a néw genus, Amphitrema. He was aware that 
in supporting Mr. Archer’s views on this subject he was venturing 
on very debateable grounds. Some, as Dr. Wallich, reasoned that 
because the animal forming the test may be of the same nature in 
a certain number of forms, it mattered not what shape, or what 
size, or what material the test should be composed of; all the forms 
having such an animal should be included in the same genus. 
Now, while such reasoning is, doubtless, to a certain extent cor- 
rect, and while Dr. Wright did not find it hard to believe that all 
the Rhizopodal forms had a common descent from single Amceboid 
form, still he believed it to be advisable, and in keeping with 
