REPORT ON THE FORAMINIFERA. 
345 
on the superior side at the inner margin of the last segment. Length, -g\jth inch 
(O' 5 mm.). 
Though easily overlooked by reason of its minute size, Trochammma pauciloculata is 
a well-marked and interesting species. It is isomorphous with the genus Allomorphina 
of Reuss, the recent specimens of which are of even smaller dimensions; but it has the 
shell-texture characteristic of its own genus, whilst Reuss’s type is hyaline and perforate. 
In its general plan of growth it closely resembles the Rotalians, notwithstanding its small 
number of segments, and their unsymmetrical disposition. The specimens, as a rule, are 
very uniform even in minor characters ; some are a little longer and others proportion- 
ately rather more compactly built, as shown in the tw T o figures, but they present scarcely 
any variation in more important particulars. 
Trochammma pauciloculata has a wide area of distribution, though the number of 
individuals found in any one locality is seldom very large. Its preference for deep -water 
is evidenced by the fact that out of twenty-two Stations fifteen have depths of more 
than 1000 fathoms. It has been taken at nine points in the North Atlantic, depth 173 to 
2435 fathoms; at two in the South Atlantic, 675 and 1900 fathoms respectively; at eight in 
the South Pacific, 420 to 2425 fathoms ; and at three in the North Pacific, 1850 to 3950 
fathoms. 
So. far as at present known, the species does not occur in the fossil state. 
Carterina, nov. gen. 
Rot alia, Carter [1877}. 
Test resembling Trocha/mmina hi contour and texture, but furnished with calcareous 
spicules proper to itself 
The presence of spicules in the test of an arenaceous Foraminifer is SO' common an 
occurrence that under ordinary circumstances it attracts but little notice ; many species 
in fact systematically employ the debris of siliceous sponges, generally in combination 
with siliceous sand, as building material. But a composite test in which calcareous 
spicules, to all appearance secreted by the animal inhabiting it, form a conspicuous element, 
is not only unusual, but marks an important structural deviation from anything otherwise 
known in this section of the Rhizopoda. Such an organism is that discovered by Mr. Carter, 
and described by him under the name Rotalm spiculotesta. But whilst its morphological 
features attest a close relationship to Trochammina, it is obvious that the presence of 
spicula, not collected from external sources for the construction of the test, but proper to 
the animal itself, is a character of more than specific significance. I therefore propose 
that it should bear the generic, or pending further research, the subgeneric name, 
Carterina . 
