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species has not, I believe, been found in any other British locality. 
I have observed Campylodiscus clypevs mixed with the before- 
mentioned Navicula in a gathering from the Great Salt Lake, 
Utah : this gathering is so like those made at Breydon, that 
were it not for a few species not hitherto found in Great Britain, 
it would he difficult to distinguish them. 
The very remarkable little form doubtfully referred by Professor 
Smith in his Synopsis to the genus Triceratium (T. exiguum), has 
hitherto only been found in Ormesby Broad : it was first observed 
some four-and-twenty years ago in gatherings made from that locality 
by Mr. II. G. Glasspoole, and it is still found in the broad. 
The late Dr. Arnott and other diatomists considered this form to 
be a variety of Odontidium mutabile, an opinion with which I do 
not concur : I should be more inclined to refer it to O. parasiticum 
(if it be not a distinct species). It is frequently found adhering 
by one of the angles to other diatoms, particularly Nitzschia sig- 
moidea, and associated with 0 . parasiticum. Mr. Brightwell has 
described and figured it in the ‘Quarterly Journal of Microscopical 
Science,’ but his figures are incorrect : the centre of the valve is 
not punctate and the margin is striate. 
Achnanthidixim ventricosum—Monogramma ventricosa, Eln*., I 
had the pleasure of detecting in the washings from moss growing 
at the foot of some willows on the Osier Car, Heigham. This 
species, I believe, had never before been found in Britain or even 
in Europe ; it occurs in great abundance in a subpeat (?) deposit 
from “ Cabbage Tree Swamp,” New Zealand, and also in a gather- 
ing from the mouth of a cave in the New Hebrides ; I have also 
seen it sparingly mixed with other diatoms collected at Petro- 
paulovski. 
The pretty little species Pinnularia globiceps was first detected by 
the late Dr. Gregory (see ‘Quarterly Journal Microscopical Science,’ 
vol. iv), in a gathering from Flordon, I think made by Mr. Bright- 
well. I have never been fortunate enough to find it myself, 
although I have carefully examined material from that locality. 
In some moss growing on the trunk of an elm on the Earlham 
Hoad, I found Dendroteres spiralis, Ehr. = Orthosira mirabilis, 
Gregory, mixed with Navicula appendiculata and N. undosa. 
The arrangement adopted (with some alterations) is that used by 
Herr Grunow in his work on Austrian diatoms. 
