PROCEEDINGS OF SOCIETIES. aay 
all alike in these particulars; the larger specimen had not got the 
rhomboidal curve at all, and the drawings showed a distinct difference 
in this respect. One had a larger nodule at one end than at the 
other ; another had a nodule at each end; the small ones had no 
nodules, but were of angular form; whilst another differed altogether 
in having a beautifully curved outline. He mentioned these differ- 
ences as bearing upon the question whether the species should not be 
determined by the shape and nodules rather than by the number of 
the striz. 
Dr. Wallich, in reply to a question from Mr. Slack, said he quite 
agreed with Mr. Ingpen that the larger specimen was distinctly 
different from the others, and that it had not the rhomboidal outline. 
He might also mention that in preparing these diatoms, if they were 
boiled too long in acid, all the material would be boiled away except 
the median column, and with a less degree of boiling they would 
constantly find the lateral parts would break away in the acid. 
The President said it appeared to him that it was a point well 
worthy of investigation whether or not there was a series of con- 
necting links between the specimens. 
Mr. Slack asked if Mr. Ingpen would examine the specimens from 
Cherryfield in his own collection, and see if they dittered in these 
respects. 
Mr. Ingpen said he would do so; the point of importance was 
whether the small specimens and the large ones were the same 
species. If he should be called upon to name the large one, he should 
hardly call it a Rhomboides at all. 
Mr. Slack suggested that if diatomists would allow Triceratium to 
go up to seven angles, they need not take much notice of such slight 
variations. 
The President said that the question before them was not the mere 
determination of species, but very important physical facts were con- 
nected with and lay at the bottom of it; which had a most important 
bearing on a very great number of investigations in many different 
branches of science. 
Donations to the Library since November 1, 1876: 
From 
IN GEUTOS VOC KL, fet erou diay Sai bis wee py l2etbd way nosed ‘pce pl ane ne Parton: 
AUTEN co UM WIECH Yet ose ticity Medes! icy sat os che se Se Ditto. 
NOCH POLEATIS S OURTIAn ese ce elec lit cs | oc) buco” yeeie ee Hicietun Nate SOCICLY/® 
Verhandlungen. 
Proceedings of the Literary and Philosophical Society of Liverpool. 
No. 30. 1876 .. Rene Ditto. 
Bulletin de la Société Royale de Botanique de © Belgique. No. 2. 
NS Gr eres Ditto. 
American Journal of Microscopy. i Now 1 Editor. 
Transactions of the Royal Irish Academy (Science). ’ Five parts .. Academy. 
Proceedings of ditto. Three parts .. Ditto. 
Six sets of ats aaiens with i Pamphlet 6 &e. By Dr. J. J. Wood- 
ward .. ap) vase os, isa) game Allanons 
William Garrow saee Esq., was elected a Fellow. 
Water W. REEVEs, 
Assist.-Secretary. 
I i ce as ae 
=  ~usm = SS 
— — 
