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Transactions of the Society . 
such synonyms as may be considered necessary for the elucidation of 
the species. At the same time attention will be called to the forms 
figured by authors under other names, when those forms have charac- 
ters differing in some respects from those of the type. 
In selecting synonyms, preference has been given to those works 
in which the species are illustrated by figures, as so many of the 
forms given by authors prove to be wrongly diagnosed, that a mere 
list of names must be always regarded with a certain amount of 
suspicion. 
The well-known tendency of the various types of Foraminifera to 
gravitate towards one another from every direction, although setting 
at defiance all strict rules of classification, can yet be made useful by 
observing in any given locality or formation the direction in which 
the different types tend to vary. To take an illustration : Discorbina 
turbo may in one locality approach D. rosacea, and in another Botalia 
Beccarii. Attention to these variations serves to indicate the par- 
ticular facies of a locality, and to show its distinguishing characters 
in a way which attention to the type forms only would fail to ex- 
press. 
For much assistance in the determination of species I am indebted 
to Prof. T. Rupert Jones and] Messrs. Chapman and Sherborn of 
London, Dr. Axel Goes of Sweden, and M. Schlumberger and the late 
M. Berthelin of Paris. 
Sub-kingdom PROTOZOA. 
Class RHIZOPODA. 
Order Foraminifera (Reticularia). 
POBCELLANEA vet IMPEBFOBA TA. 
Family II. MILIOLIDiE. 
Sub-Family I. Nubecularinse. 
Nubecularia Defrance. 
Nubecularia fusiformis sp. n., plate Y. figs. 1 and 2. 
Test free or (?) adherent, monothalamous, elongate, fusiform, more 
or less flexed, with a circular aperture at each extremity. Length 
0*7 mm. 
This is a porcellanous isomorpli of Lagena gracillinia, and bears 
the same relation to N. tibia that the Lagenee bear to the Nodosariae, 
but it does not seem necessary on that account to create a new genus 
for it. It shows no tendency to become jointed, but some specimens 
have a lateral supplementary aperture, and sometimes one of the ter- 
minal apertures has a thickened margin. It occurs sparingly in both 
areas. 
