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THE VOYAGE OF H.M.S. CHALLENGER 
reveals no characters not common to the entire series, none at any rate that can be 
regarded as zoologically distinctive. 
Nubecularia tibia occurs at five of the Challenger Stations, always in compara- 
tively shallow water, namely: — off Culebra Island, West Indies, 390 fathoms ; off Raine 
Island, Torres Strait, 155 fathoms ; Humboldt Bay, Papua, 37 fathoms ; Philippine 
Islands, 95 fathoms ; and the Inland Sea, Japan, 15 fathoms; but it is by no means a 
common form at any of these localities. 
The interest attaching to this simple little organism depends upon the fact that until 
lately it had only been recognised as a Triassic or Rhsetic fossil. It was first described by 
Jones and Parker, loc. cit., in their paper upon the Foraminifera of certain marls occurring 
at Chellaston in Derbyshire. More recently I have identified specimens in Mr. E. A. 
Walford’s collection of microzoa from the Upper Lias of Banbury, and this completes 
the record of its geological history ; it is nevertheless quite possible that, owing to its 
minute size and inconspicuous appearance, it may have been overlooked in other 
localities. 
Nubecularia divaricata, H. B. Brady (PI. LXXYI. figs. 11-15). 
Sagrina divaricata, Brady, 1879, Quart. Journ. Micr. Sci., vol. xix., N. S., p. 276, pi. viii. figs. 22-24. 
Test free, moniliform ; consisting (typically) of three or four more or less distinct 
segments, united by stoloniferous tubes. Segments subglobular, rough and arenaceous 
externally; stoloniferous tubes narrow, cylindrical, with thin calcareous walls, and 
smooth externally. Aperture an elongated tubular neck, often longitudinally furrowed, 
terminating in a phialine lip. Length, ^th inch (0’5 mm.). 
The further study of this interesting little organism has led to considerable 
modification of the terms employed in the original description ; for, misled on the one 
hand by the delicately thin and almost transparent stoloniferous tubes, and on the other 
by the subarenaceous tests of some of the forms included by d’Orbigny in the genus 
Sagrina, the species was placed, to begin with, in a wrong position. It is, in fact, only 
by the careful examination of the shell, in section and otherwise, by transmitted light, 
that the porcellanous texture of the walls can be satisfactorily made out ; but viewed in 
this way the test exhibits all the structural features of the arenaceous Miliolce. 
The stoloniferous tubes vary a good deal in length, or at any rate in the extent to 
which they are visible. In some cases the length is as much as half the diameter of the 
segments, whilst in others the neighbouring segments appear closely approximated, and 
the stolons are scarcely seen, owing to the increased thickness of the sandy incrustation. 
The phialine neck often resembles that of Nubecularia tibia, but it occasionally takes 
exaggerated forms such as those represented in figs. 15, 16. 
