83 
most treacherous guide) varies in this species from 60 to double that number. 
For example— No. 138 has 60, 64, 68, the younger marginal corralites having 
of course the smaller number of septa. No. 131 has 62, 64, 68, 78, 72 septa ; 
No. 137 has 68, 80, 72, 76, 78, septa; No. 126 has 72, 78, S5(?), 101(?), 106, 
septa; and in No. 145 I count 104 and 116. The external character of the 
calices is also very variable, — now concave, now fiat, now again convex, nay 
almost towering up in the centre. 
But this C. regium, is it really a distinct species from the preoseding, 
viz. C. Stutchburyi? I think not. The latter in my opinion is but the simple, 
and the former the compound, massive form of one and the same coral. C. 
Stutchburyi has not had time to produce germinations, has probably grown 
up in stations, which became rapidly silted up (and this the marley beds, in 
which we find them, prove,) has had to throw all energies into the maintain- 
ance of its own individual life. C. regium on the contrary could grow 
massive, reef -like, could develope latterally by germinations, no such call 
being made upon the vital powers to rapidly develope in height to overcome 
adverse circumstances. For I can see no difference between the two species 
in their internal structure. Moreover in No. 142 we possess a specimen, 
composed of two corallites, not as in No. 127, (the one figured in the Mono- 
graph) each calyx perfectly indepedent of the other, but united by vesicular 
structure ; the numbers of septa in these two corallites is 104 and 116, and 
the height of the specimen intermediate between the typical C. Stutchburyi 
and the massive C. regium. No. 102 then presents us with a specimen, in 
which three calices are united, having 120, 124, 126 septa, the height of coral - 
lum intermediate. And these are by no means solitary instances of so few as 
2, 3, 4, &c, corallites united, but I may safely say that I have met with more 
than a dozen of such specimens from our rocks, and that without searching 
for them. I am more doubtful however, whether it be right to regard 
" Turbinolia expansa, Mc. C," as specifically identical with C. Stutchburyi, 
though it certainly would be difficult to separate them by a good and sharp 
definition. The remaining species parracida, Mc. C, C. psendo-vermiculare, 
Mc. C, C. dianthoides, Mc. C, G. Archiacis, M. Ew., are I am sorry to say, 
not represented in the collection. 
(Want of time did not permit the author to complete his review of the 
collection ; but he has promised to do so at some future meeting of the 
Geological Section.) 
