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THE VOYAGE OF H.M.S. CHALLENGER. 
wrinkled. Another variety, fig. 4, has a somewhat thicker investment closed at one end, 
and the surface is often beset with short sarcode-filaments, which, being apparently less 
mobile and retractile than true pseudopodia, remain extended in specimens preserved in 
alcohol. These and some other obscure chitinous forms must be left for future investi- 
gation. 
Scigenellci, H. B. Brady. 
Sagenella, Brady [1879], Biitsclili. 
Test an adherent, branching, reticulated, arenaceous tube, with terminal apertures. 
Amongst the minute parasitic organisms often found in great abundance on stones 
and shells dredged from the sea-bottom, especially in the shallow waters of the tropics, 
there are many of which it is difficult to decide the zoological origin. Some of the 
most problematical of these take the form of simple or branching tubes, the structural 
features of which are not unfrequently further obscured by a rough sandy exterior. 
There are already many well-known, adherent, tubular Foraminifera of arenaceous 
texture, some of which like Hyperammina vagans are simple and undivided, whilst others 
like Placopsilina and Bdelloidina are more or less distinctly segmented. The specimens 
on which the genus Sagenella has been founded, differ from these in important 
particulars : from Hyperammina, in that they have no primordial chamber, but branch 
indefinitely on all sides, and from the Lituoline genera in the absence of segmentation. 
The frequent inosculation of the tubes is also a very distinctive feature. 
So far as my observation goes, specimens with these characters are rare, and 
considerable care is needful in separating them from bodies of very different origin. 
Since the publication of the provisional description of the present genus several specimens, 
supposed to be related to the figured species, have been sent to me for identification, not 
one of which could be recognised with any certainty as Foraminiferal. The organisms 
most frequently confounded with it have been the branching or reticulated creeping 
stolons of certain genera of Hydroida ; but other minuter dendritic creatures of various 
sorts, both animal and vegetable, have also at times been assigned to the group, and new 
species proposed for their reception. 
Sagenella frondescens, H. B. Brady (PI. XXVIII. figs. 14, 15). 
Sagenella frondescens, Brady, 1879, Quart. Journ. Micr. Sci., vol. xix. N. S., p. 41, pi. v. fig. 1. 
Test adherent ; consisting of long, finely arenaceous, tubular passages, ramifying and 
forming a sort of irregular network over the surface of shells or other bodies. Branches 
bifurcating ; each final branchlet terminating in a neatly rounded aperture. Colour white 
to very light brown. Size indefinite ; diameter of the larger passages about 
inch (0’4 mm.), of the smaller branches ^^th inch (0T2 mm .). 
