NOTES ON RETICULARIAN RHIZOPODA. 53 
depressed at the sutures. Consists of two to three con- 
volutions, of which the final one has about nine seg- 
ments. Diameter, ;!> inch (0°5 mm.). 
Cyciammina, Brady. 
The genus Cyclammina is of considerable importance, 
inasmuch as it presents the best development amongst living 
Foraminifera, of finely tubular cancellated growths of shell 
substance filling the chamber cavities—a sort of structure 
differing widely from the mere subdivision of the chambers 
by the building in of large sand-grains, which is not un- 
common amongst arenaceous types. ‘There are two interest- 
ing modifications of C. cancellata amongst the ‘‘ Challenger” 
gatherings, which, though perhaps only local varieties, differ 
sufficiently from the typical form to deserve distinctive 
names. 
Cyclammina orbicularis,nov.—A subglobular variety, bearing 
about the same morphological relation to the type 
that Nonionina pompilioides does to N. depressula, only 
that it is of much smaller size. 
C. pusilla, nov., has a minute, biconvex test, depressed at 
the umbilici, and with thin, sharp, slightly lobulate 
periphery. A horizontal section shows that it consists 
of about three complete convolutions, the last of which 
has about fifteen segments. The cancellated structure 
is but little developed, there being only sufficient to 
form a superficial reticulation over the inner surface of 
the chamber walls. Diameter, =4 inch (1: mm.). 
TEXTULARIA, Defrance. 
Textularia siphonifera, nov.—Test subcylindrical, nearly 
-roundin transverse section, tapering and pointed at the 
. primordial end ; each of the two opposing series of cham- 
bers furnished with from two to four rows of tubulated 
fistulose openings, arranged with more or less regularity. 
Length, ;/; inch (1'5 mm.). 
BicENERINA, d’Orbigny. 
Bigenerina robusta, nov.—Test elongate, compressed in its 
earlier (biserial) portion, cylindrical in its later (uni- 
serial) growth. Uniserial segments numerous, short, 
somewhat irregular, often ventricose at their periphery. 
Aperture simple and Textularian in the biserial seg- 
ments, becoming multiple and porous in the uniserial 
portion ; the pores either arranged in a ring or irregu- 
