REPORT ON THE FORAMINIFERA. 
589 
Globigerina, as well as in those of Pullenia , and also in the genus Hastigerina , the 
aperture is a broad curved fissure, symmetrically placed at the inner margin of the 
segments. In some turbinoid species the aperture is single, and only differs from that of 
the Rotcilince in its relatively large size ; in others it is divided, and takes the form of 
a number of smaller orifices, part of which are situated on the superior face of the test ; 
whilst in Orbulina, there is no general orifice in the ordinary sense of the term, its place 
being supplied by a set of abnormally large perforations. 
As already stated, the constituent genera of the Globigerinida do not arrange them- 
selves in a continuous series like those of the Miliolida or the Lagenida, but form several 
collateral groups, of which the corresjDonding modifications exhibit to a limited degree 
the sort of isomorphism that is so conspicuous a feature of the Kotalida. Thus 
Globigerina bulloides finds an isomorph in Candeina nitida ; Globigerina conglobata, 
Sphceroidina bulloides, and Pullenia obliquiloculata are in like manner parallel modifica- 
tions of their respective types ; as are also Globigerina cequilateralis, Hastigerina pelagica, 
and Pullenia quingueloba. In connection with this subject it is of interest to note that 
similar isomorphisms may be traced between the Globigerina and the Rotalince, though 
the number of corresponding forms is relatively small. 
The most noteworthy characteristic of the Globigerinida as a Family is the pelagic 
habit of most of the species. Certain genera, like Hastigerina, are exclusively pelagic; and 
of others a great majority of the known varieties have been found in the free-swimming 
condition. Even Pullenia and Sphceroidina , of which the reputed typical species have 
only hitherto been met with in bottom-dredgings, have well-marked pelagic 
representatives. 
Globigerina, d’Orbigny. 
Globigerina, d’Orbigny [1826], Eoemer, Eeuss, Bailey, Ehrenberg, Costa, Parker and Jones, 
Egger, Williamson, Pourtales, Karrer, Carpenter, Wallieli, Brady, Owen, Sell wager, &c. 
Rosalina, pars, d’Orbigny [1839], Ehrenberg, Eeuss, Rupert Jones. 
Rotalia, pars, Ehrenberg [1854], Kiibler and Zwingli. 
Phanerostomum, pars; Ptygostomum, pars; Planulina, pars, Ehrenberg [1854]. 
Rhynchospira, Ehrenberg (?), Eeuss, MS., Karrer [1877], 
Pylodexia, Ehrenberg [1859]. 
Rotalina, pars, Seguenza [1862]. 
Aristerospira, pars, Ehrenberg [1873]. 
The distinctive characters of the genus Globigerina are stated by d’Orbigny in the 
“ Tableau Methodique ” in the following terms : — “ Test fibre, trochoide, irregulier ; spire 
confuse, formce par des loges spheriques plus ou moins distinctes ; ouverture en forme 
d’echancrure plus ou moins profonde, situee vers Taxe de la spire a l’angle ombilical .” 1 
The genus is described at considerable length by Dr. Carpenter and his colleagues in the 
1 Ann.. Sci. Nat., 1826, vol. vii. p. 277. 
(ZOOL. CHALL. EXP. — PART XXII. 1884.) 
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