DIATOMACEZ. : 29 
Dolgelly earth. Cwm Bychan is, however, fifteen miles from 
Dolgelly. I do not offer anything new in the way of classi- 
fication, but have followed that of Pror. Kurzina, as given in 
Pritchard’s “Infusoria.” In all that relates to the identification 
of species I have followed Wm. Smiru’s ‘Synopsis of British 
Diatomacee,”’ and have always found his figures most reliable. 
I have used abbreviations for the authority of the Genus and 
Species, which will be easily recognised by those who study the 
subject. I cannot pretend that this list is exhaustive, since I 
have only entered those names of which I was certain. The 
number of synonyms, under which some of the forms are known, 
has made no little confusion, and I have therefore been careful 
not to increase this difficulty. 
The number before the Species marks the slide in the Cabinet 
of the Society ; in the last column vr (very rare) signifies that 
the form has only been found in one gathering; r (rare), found 
in two gatherings; ¢ (common), found in three gatherings; 
Vv c¢ (very common), found in four or more gatherings. 
The locality given is generally that in which the form was. 
first recognised, although it may occur abundantly in other 
gatherings. 
The date given is that when the collection was made. 
FAMILY I.—EUNOTIE. 
No. Name. Locattty. OccuRRENCE. 
EpitHemia, Kutz. 
39 alpestris, Sm. ......| Heron Bridge Rocks ....| Dec. ’73...... r 
22 Argus, Sm.....°***| Llangollen. ............. Aug. ’72.....1 
5 constricta, 2. sp.....| Mostyn ........ eee || MUL, 27 lees WC 
10 gibba, Kutz ......| Helsby Marsh .......... March ’72..v¢ 
18 Hyndmanii, Sm,...| Parkgate .............. June ’72...vr 
22 longicornis, EAr, ..| Llangollen.............. Aug. ’72...v1r 
58 proboscoidea, Kutz. | Cemetery Pond, Chester..| May ’71....vr 
17 rupestris, n. sp, ....| Cwm Bychan deposit ....| -.........: vr 
39 sorex, Kutz ..... ...| Heron Bridge Rocks ....| Dec. ’73....vr 
13 turgida, Sm. ......| Frodsham Marsh........| March’72..ve 
39 ventricosa, Kutz....| Heron Bridge Rocks ....|} Dec. ’73....v r | 
24 zebra, Kutz........ Combermere ............ March ’73..vr 
This genus is well represented. The only form that I have 
E 
