EEPOET ON THE FOEAMINIFEEA. 
597 
amount of reservation, as it is impossible to realise properly the characters of Globigerince 
from their appearance as transparent objects. Some of the illustrations quoted are 
manifestly drawn from very young and others from immature individuals. 
I have never met with recent specimens, either amongst surface-organisms or in 
bottom-ooze, which presented exactly the same characters as the typical Cretaceous 
variety ; though shells similar in general conformation, and more nearly related to 
Globigerina cretacea than to any other recognised modification of the genus, are not 
uncommon in certain localities. Such specimens, one of which is represented in 
PL LXXXII. fig. 10, are, as a rule, more stoutly built than the typical form; and the 
segments are less numerous and of proportionately larger size. They are not unlike 
many of the fossil specimens figured by Ehrenberg. 
This species is probably the commonest and most widely diffused of all the Cretaceous 
microzoa. 
Globigerina marginata, Reuss (Woodcut, fig. 17). 
Rosalind marginata, Eeuss, 1845, Versfcein. bohm. Kreid., pt. i. p. 36, pi. xiii. fig. 47. 
„ „ Jones, 1853, Ann. and Mag. Nat. Hist., ser. 2, vol. xii. p. 241, pi. ix. fig. 7. 
„ „ Eeuss, 1854, Denkschr. d. k. Akad. Wiss. Wien, vol. vii. p. 69, pi. xxvi. fig. 1. 
Discorbina marginata, Id., 1865, Sitzungsb. d. k. Ak. Wiss. Wien, vol. lii. p. 12, No. 2. 
Globigerina marginata , Parker and Jones, 1865, Phil. Trans., vol. civ. p. 367. 
Rotalia marginata, Giimbel, 1870, Sitzungsb. d. k. bayer. Akad. Wiss., vol. ii. pp. 283, 287. 
Globigerina marginata, Eeuss, 1874, Das Elbthalgebirge in Sachsen, 2 ter Theil, p. 112, No. 2. 
„ ‘ „ Brady, 1879, Quart. Journ. Micr. Sci., voL xix., N. S., p. 74. 
Test Rotaliform, much compressed ; superior face convex, inferior face also convex but 
with a sunken umbilical recess, peripheral edge thin or subcarinate ; segments numerous, 
five or six in the last convolution, the outer margin of each segment exhibiting a well- 
marked narrow border ; apertures opening into the umbilical vestibule. Surface of 
living specimens beset with spines. Diameter, ^th to -^th inch (0’5 to 1 mm.). 
Messrs. Parker and Jones, in their memoir on Foraminifera from the North Atlantic 
and Arctic Oceans ( loc . cit.), recognise the Globigerine affinity of the “ complanate form 
with more or less limbate septal lines,” typified by the Rosalina marginata of Reuss. 
Indeed they go somewhat further, and class together with this typical variety the Rosa- 
lina canaliculata of the same author, and the Rosalina linnceana of d’Orbigny, as 
pertaining to one and the same species. Of the generic affinity of the forms referred to, 
and of their close relationship to each other, there can be little doubt. They nevertheless 
appear to include representatives of two easily distinguished varieties, the one characterised 
by its thin subcarinate peripheral edge, the other by its thick and almost square or some- 
times even bicarinate margin; and in the foregoing Scheme (p. 592) the terms Globi- 
gerina marginata and Globigerina linnceana have been retained for them respectively. 
It is stated by Reuss that the entire surface of the fossil shell is hispid or beset 
(ZOOL. CHALL. EXP. —PART XXII. — 1884.) Y 76 
