Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/158

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124 PROCEEDTNGS OF THE GEOLOGICAL SOCIETY. [Jan. 24,


Supplement.

In the foregoing paper we have compared side by side several described sets of Rotalinoe from the Cretaceous and Tertiary rocks, and from the present seas. We know how imperfect the materials for this critical collocation really are, and that the sketch view we get of them in the foregoing Tables is but a glimpse into a wide and unexhausted region. Numerous as the forms are that we have catalogued in their zoological order, for comparison by the naturalist, and fertile as they are in suggestions as to range and relative persistence, we do not forget the wholesome caution to Rhizopodists clearly and forcibly given by Prof. W. C. Williamson years ago, when treating of the then new and striking researches of Ehrenberg and D'Orbigny : — "We must not cloud the evidence afforded by the higher animals with that derivable from beings so much lower in the scale of organization, and which, as a whole, are so far removed from the influence of external agencies. The study is at once so novel and so fascinating that all who pursue it, impressed by its singular interest, are in danger of being allured by it beyond the bounds of caution, — a tendency which is ever promoted by the announcement of comprehensive hypotheses and splendid novelties." — ' Microscop. Objects found in the Mud of the Levant,' p. 126. Memoirs Manchester Lit. & Phil. Soc. vol. viii. 1847.

To make our subject as clear as known facts can help us to make it, we here subjoin further lists of local groups of Rotalinoe, both Recent and Tertiary, prepared, on the same system of nomenclature, for rigid comparison with those in the body of this paper. From a study of these additional catalogues it will be found, as with the others, that, for the most part, numerous slight varietal differences, local and mainly recognizable in the fades of the group — indeed, only to be brought out by good drawings, and scarcely describable, — are important elements in the successional diversity that really obtains among the Foraminifera. These slight, but important, shades of difference give rise to great multiplicity of names. This is a trouble which we have endeavoured to deal with judiciously in all our lists, basing our nomenclature on the principles laid down in our memoirs in the 'Ann. Nat. Hist.,' in the ' Phil, Trans.' vol. clv., and in Carpenter's ' Introd. Foram.' 1862.

§ 1. — Recent Foraminifera.

I. In further illustration of the Foraminiferal fauna of the Pacific Ocean (see list, p. 115), we here offer a corrected list of the Foraminifera found by Mr. G. D. Macdonald among the Fiji Islands. See Ann. Nat. Hist. ser. 2, vol. xx, pp. 193 &c., 1857.

From 1020 fathoms.

Pl. 5. f. 1 & 2. Doubtful. f. 3-5. Polycystina.

From 440 fathoms.

f. 6. Uvigerina pygmaea, D' Orb., dimorphous variety.

f. 7-10. Lagena globosa et marginata (Montagu), Entosolenian,