PROCEEDINGS OF SOCIETIES, zs 
modern ideas of classification, to take certain well-marked differ- 
ences—which must in most instances be arbitrarily selected—and 
to place the animals possessing these differences into groups by 
themselves. It was not of much consequence whether these 
groups received the name of genera or species, as long as these 
' differences were sufficiently constant to be easily recognised. In 
the case of Amphitrema, although the test was something of the 
same nature as that met with in some species of Difflugia, and 
although the animal itself did not appear to differ essentially from 
some other actinophryan testaceous Rhizopods, still, finding it 
always provided with two orifices for the emission of its pseudo- 
pods, and those pseudopods of a radiolarian type, entitled it, Dr. 
Wright thought, to generic distinction, and this opinion would 
not be altered by the even strong probability of its being a tran- 
sitional form between an amceban and an actinophryan, so covered 
with a chitinoid test, and loaded with mineral matter, that, except 
through these two openings, it was unable to protrude its pseudo- 
pods. Dr. Wright had alsofound Cyphoderia margaritacea(Schlumb.) 
in a gathering from the Castle grounds at Parsonstown. The 
general resemblance that this form bears to Lagynis baltica of 
Schultze, as figured by Carpenter, was very great; but Dr. Wright, 
having seen a specimen, was not prepared to regard Schultze’s 
species as only a variety of Schlumberger’s. At the same time, he 
agreed with Dr. Wallich that there was no occasion for the sepa- 
ration of Cyphoderia from Dujardin’s genus Euglypha. 
The Rey. E.O’ Meara exhibited two newspecies of Surire!la, which 
he named 8. pulcherrima and S. gracilis, descriptions and figures of 
which will hereafter appear in this Journal. 
December 20th, 1866. 
Dr. John Barker exhibited the larval state of a small dipterous 
insect, affording another pretty instance of “homes without 
hands.” The larva was in great part enveloped in a compressed 
quadrangular case, expanding towards the posterior end, elliptic 
in section; the aperture elliptic, semi-trumpet-shaped, everted 
and a little flattened. Through this the larva protruded its head 
and three pair of legs, which were long, and, with the exception 
of the first pair, which were short and ended in a forceps, were 
armed with long and slightly curved, unequal hooks. By means 
of its legs the creature crawled along the bottom and sides of the 
vessel, carrying the case swinging obliquely above. The two 
valve-like sides of the case approximated towards the base, so as 
to present a slit ; it seemed composed of structureless chitine, with 
a few hairs on its surface. It was about <,” in length, and 2,” 
broad at the base. The larva, after it had been in confinement 
