NOTES AND MEMORANDA. 
259 
Nottingham, Maryland." As the Nottingham earth came from our 
corresponding member, Professor Christopher Johnston, of Baltimore 
— and that it was possible that Nottingham was the original locality, 
was well known in this country independent of Mr. Norman — I 
applied to Professor Johnston for the authentic history of that deposit ; 
to which he replied by the paper herewith appended. Mr. Norman's 
paper is in the ' Quarterly Journal of Microscopical Science,' January, 
1861. In that paper he does not say that the Bermuda came from 
Nottingham, as " F. K." represents, but only suggests the possibility 
of the case, as American diatomists had before him. Since Dr. 
Johnston's paper was written, Dr. Josiah Curtis has visited that part 
of Maryland, and discovered numerous other localities of the diatoma- 
ceous earth, containing the same forms as the Bermuda and Nottingham 
deposits. 
About the Bediscovery of tJie " Bermuda Tripoli," near Nottingham, on 
the Patuxent, Prince George's County, Maryland. By Christopher 
Johnston, M.I). 
In 1854 I had the great pleasure of being a correspondent of 
Professor J. W. Bailey, of West Point, and during the year received 
from that distinguished gentleman valuable guidance, and also speci- 
mens of diatomaceous material, among others a very small portion of 
a buff-coloured dust, labelled " Bermuda Tripoli." From this I pre- 
pared a single slide, now in my possession, containing very beautiful 
forms, chiefly Heliopelta, Coscinodiscus, Craspedodiscus, Aulacodiscus 
crux, and Eupodiscus Bodgersii. At a later period I was in correspond- 
ence with my friend J. SuUivant, Esq., of Columbus, and while making 
some exchanges, I asked for " a good boiling of Bermuda Tripoli ; " 
to which request Mr. S. replied, June, 1859, " I would send you a 
quantity if I had it. I have nothing but a slide, and I have been long 
struck with its resemblance to the Eichmond earth In a letter 
m just received from Mr. Geo. Norman, he says, ' What a pity the locality 
of Bermuda Tripoli and its beautiful fossils has been lost ; ' and then 
adds ' that himself and Dr. Arnott had come to the separate and inde- 
pendent conclusion that they never came from Bermuda at all, but from 
Bermuda or James Eiver in Virginia.' I have very little doubt of it, 
for there is a place called ' Bermuda Hundreds ' on the James River. 
From the frequent intercourse between Baltimore and Richmond, you 
have an opportunity of following this up. I trust you will." Early 
in 1860 I sent my " Bermuda " slide to Columbus, where the beauty 
of the diatoms was much appreciated, and Bermuda Hundreds again 
the subject of remark, as appears by a letter from Mr. Sullivant, dated 
March 25, 1860. I laad resolved to visit Bermuda Hundreds for the 
purpose of making an exploration, when, about the 1st of April, my 
valued friend, P. T. Tyson, Esq., State Geologist for Maryland, sent 
me a number of small parcels of " Tripoli," which he had procured in 
different parts of the state. One of these earths, marked Nottingham, 
attracted my particular attention, for I had the extreme pleasure to 
find in it the diatomaceous forms familiar on my Bermuda Tripoli 
slide, besides a host of others, and I at once was satisfied that the 
VOL. xm. u 
