MELVILL: THE PRINCIPLES OF NOMENCLATURE. 479 
in the Metropolis. I cannot help suspecting the identity of 
many more recent molluscs with those of the Tertiary forma- 
tions than is commonly supposed to be the case, not so much 
among the larger species as the smaller, and especially in such 
a family as the Pleurotomide. 
Of all the molluscan families, this more sorely needs a 
competent monographer than any other. From every point of 
view, specifically, bathymetrically, or in whatever other way they 
are considered this assemblage is of surpassing and marvellous 
interest. The multitudinous variety of form, the extensive 
abysmal distribution, the bizarre colouring of some, and sculp- 
ture of others, the large proportion, in comparison with the 
species, that are found of the “minutiora” of this family on 
some tropical shores, e.g., Lifu, which Mr. Standen and I are 
now engaged in working out, and the great quantity of new 
forms that are continually cropping up, all of exquisite grace 
and beauty, force one to the conclusion that here is congre- 
gated the most attractive assemblage in the whole range of 
marine shells. 
The day may be far off before such questions are fully 
worked out and finally solved, and few of us, if any, will pro- 
bably live to see it, but whenever the labour be accomplished, 
and a monumental task it will be, it will be seen how naturally 
every form dovetails, as it were, into its place, how beautifully 
the law of evolution extends, how the great Author of all 
things created and uncreated, magnifies, if one may so speak, 
His powers in the calling into being of the lesser branches of 
animated nature, and we shall all echo the words, so long ago 
written, of the great Roman naturalist, Caius Plinius Secundus, 
‘In his tam parvis, quam inextricabilis perfectio.” * 
4 TOW on ING Valo, 1 Dy ie 
