x INTRODUCTION. 
new species, and new views of classification, in one of the quarterly journals of science; and 
he has shown this forbearance, again and again, contrary to my express wishes. Of this 
forbearance I will mention one instance; especially as it is connected with the greatest 
mistake, in the enumeration of fossil localities, that has been made in the following work. 
Graptolites had been found in various parts of the frontier chain of Scotland:— 
by J. Carrick Moore, Esq. in the western extremity of the chain—by the same gentleman 
and myself (1841) in some new localities farther inland—by Sir William Jardine in one 
or two localities in Dumfriesshire, which he pointed out to us in 1841—and afterwards by 
Professor Nicol in some fine quarries in the upper part of the Tweed. But in 1848, 
I found, to my great surprise, that within a circle of ten or twelve miles in diameter— 
described from a centre near Moffat—was enclosed a country abounding in great beds of 
carbonaceous and pyritous alum-slate alternating with sandstone; and that the alum- 
slates, in places without number, contained Graptolites in vast abundance. 
Many specimens were collected by my friend John Ruthven and myself, (in 1848), from 
the valleys descending from the south side of Harter Fell; from the valleys and ravines 
on both sides of Moffat Water, and especially from some ravines above the branch of the river 
which falls over the “Grey Mare’s Tail;’ from valleys north of Beatock Bridge which 
branch from the line of the rail-road; from numerous quarries, and (fruitless) openings 
in search of coal, in the country round Moffat; from various water-courses on both 
sides of the road from Moffat towards Locherby; from the water-course above Breconside, 
&e. &e. With a change of mineral type in the rock, the Graptolites gradually disappear; 
but one specimen was found in the cutting of the rail-road about two hundred yards 
above the Locherby Station. 
In conformity with the general plan of this work, all these localities would have appeared, 
each in its proper place, in the systematic description of the Graptolites, had not the specimens 
been so much damaged and mixed together in their passage to Cambridge, that their accurate 
separation became impossible. By myself they were therefore all packed together as the Grap- 
tolites of the “ Moffat group;” and under that general name the species were enumerated in 
a paper read before the British Association at Edinburgh in 1850*. 
By the greatest geographical mistake committed in the First Fasciculus the name 
Locherby has been affixed to the several species derived from the Moffat group. How 
the mistake originated is more than I can tell. None of the proof-sheets of the following 
work were revised by myself. Some of them were printed while Professor M°Coy was in 
Ireland, and others during the vacations when I was absent; and he had not visited any of 
the localities. It only remains for me to express my regret for this mistake, and to request 
the reader of those early pages of this work (p. 3 to p. 9) which contain M*Coy’s Graptolitide, 
to expunge the word Locherby wherever it occurs, and in its place to substitute the words 
Moffat group. 
* Report of the British Association for 1850, Transactions of the Sections, p. 107. 
op I 
