2G6 
THE GEOLOGIST. 
of the Pitherella Uichnanii is due to my own casual negligence. The specimen 
found by Mr. Jones was placed by him in my hands months before the Dulwich 
drainage-works were begun ; and I requested Mr. Jones to show it to Mr. 
Etheridge and Professor Morris, which, I believe he did ; and by whom I also 
believe the shell was called a Voluta. Not being satisfied with the vague kind 
of opinion given to hiin, and the doubts expressed regarding it by those eminent 
palaeontologists, Mr. Jones again left the specimen in my hands, and I placed 
it aside for careful examination and study ; but numerous professional engage- 
ments, as well as domestic matters, at that moment engrosing my thoughts, it 
remained unattended to by me ; and was not, singular to say, recalled to my 
mind, even when making the drawings (which I did myself) of Mr. Rickman's 
specimens, both for this journal and for the Illustrated News. I am sure this 
frank acknowledgement of my " sin of omission" will be a sufficient apology to 
my young friend, Mr. Jones. The indefatigable perseverence of Mr. Rickman 
in working out not onlv the fossils, but the stratigraphical details of that portion 
of the drainage works w^ell deserves the little honour that is attached to the triviale 
nomen of a new shell, of which honour I am sure neither Mr. Jones nor myself 
would wish to see him deprived, especially as Mr. Rickman's discovery was 
perfectly distinct from Mr. Jones' : the former not having any knowledge, as 
far as I know, of what the latter had done. 
Mr. Jones is an active geologist, willing to do good work, and our regret is 
that he was not more encouraged to continue his researches by those naturalists 
to whom he showed the original specimen. 
I am not clear that there may not be two species of this new genus, and I 
have just sent two specimens handed me by Mr. Arthur Bott of Peckham, 
to Mr. P. E. Edwards, for his inspection and decision. In this case it would be 
fair Mr. Jones should be honoured with the specific denomination — a slight 
glorification as rightly due in his case as in Mr. Rickman' s — more than usually 
can be said when personal names are so commonly attached as mere compliments 
to naturalists who have never seen the objects named after them; or in com- 
memoration of amateur-geologists, who have bought their specimens of working 
collectors. — S. J. Mackie. 
New Species oe Trilobites. — Sir, — I saw some weeks ago an advertise- 
ment by Mr. Gregory, on the cover of The " Geologist," stating that he had 
many specimens of Agnostis venulosus, from the Lingula flags ; but I should 
not have noticed the blundering use of a mere MS. name, given by me to a 
friend for his collection, had I not seen (in p. 212 of your last number) an 
article by Mr. Gregory, giving three or four other MS. names in the 
same way — all of which are wrong ; and certainly they ought not to have been 
published, whether right or wrong, for they have not yet appeared in any shape. 
Lest these mischievous advertisements should be repeated, I must correct the 
reference so far as to say that the species of Asaphus, and the shells referred 
to, are from the " Lower Tremadoc slates" — not from the Lingula flags, in which 
no true Asaphidse occur. 
I shall take this opportunity of advertising in a scientific sense, requesting 
those gentlemen not personally known to me, who may be possessed of good 
collections of trilobites, to communicate to me their willingness to lend 
specimens for illustration in the Palaeontological Society's Transactions. 
I hope I may take this means of becoming further acquainted with collections 
of this beautiful group of fossils. As only a few genera will be illustrated at 
a time, no unreasonable detention of the specimens will occur. — J. W. Salter, 
Geological Survey Office, Jermyn Street. 
