68 Dr. W. B. Carpenter on the Shell-structure of 
descends from the neck to the ventral fins. The brown portion 
of the body coarsely reticulated with yellowish, the lines de- 
scending from the back to the belly. Caudal fin and a cuneiform 
band along the hinder half of the base of the dorsal yellow. 
North-west coast of Australia (Duboulay). 
IX.—On the Shell-structure of Spirifer cuspidatus, and of certain 
allied Spiriferide. By Wiiit1am B. Carrenter, M.D., 
F.R.S. 
To the Editors of the Annals of Natural History. 
¢ 
GENTLEMEN, 
Being now in a condition to give a complete and explicit 
reply to the question raised by Mr. Meek, on which I addressed 
you six months ago (Ann. Nat. Hist. Jan. 1867, p. 29), I take 
the earliest opportunity of communicating to you the results of 
my researches, which will be found, if I mistake not, of singular 
interest to such paleontologists as pay special attention to the . 
Brachiopoda. 
I think it due both to Mr. Meek and to myself to point out 
that the note in the ‘ Annals’ for August,’ 1866 (p. 144), in 
which he is represented as calling in question the accuracy of 
my original observations on the imperforate structure of the 
shell of Spirifer cuspidatus, did not correctly express his views. 
In a letter with which he favoured me immediately on reading 
my previous communication he says :— 
“JT am sorry you had not seen my little paper before you 
read the notice of it to which you allude. If you had done so, 
I am sure you would have at once seen that I made no attempt 
whatever to cast doubts upon the accuracy of your investiga- 
tions. I never for a moment questioned the fact that the shells 
examined by you are not punctate. The only question with me, 
after seeing, as I believed, very minute and very scattering 
punctures in the shells I had examined, was, whether there might 
not be in Ireland, and possibly in England, another rare type, 
not seen by you, indistinguishable by form and other external 
characters from S. cuspidatus, and yet widely separated by 
having a punctate structure. Believing that this might be the 
case, and knowing that, if so, it would be a matter of some in- 
terest to know which was the true cuspidatus, I published my 
remarks mainly in order to cause further investigations. 
“As you have doubtless ere this seen my little paper, you 
must have observed that the words ‘contrary to the opinion of 
Dr. Carpenter,’ quoted by you, do not occur in it, nor any others 
