REPORT ON THE FOR A M TNTEER A . 
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comparatively slight ; walls thin, rough externally. Length indefinite, specimens seldom 
found with either end entire ; sometimes ^th inch (2 mm.) or more. 
Reophax adunca, as ordinarily met with, consists of a moniliform line of slightly in- 
flated segments so nearly alike that it is difficult to say which is the growing end of the test ; 
indeed it is quite possible, for any evidence that exists to the contrary, that it may put 
on fresh segments at either extremity. It resembles to some degree both Reopliax 
guttifera and Hormosina monile, but is less regular in outline and has thicker stolons 
than the former ; and its want of regularity, comparatively small size, and rough exterior 
distinguish it from the latter species. 
Reophax adunca is found as far north as the Faroe Channel, 540 fathoms ; and at 
about the same latitude in mid- Atlantic, 1750 fathoms; south of Rockall Bank, 1215 
fathoms ; and off the Canaries, 1125 fathoms. It occurs at three Stations in the South 
Atlantic, 675 to 2200 fathoms; at two in the Southern Ocean, — between the Cape of 
Good Hope and Kerguelen Islands, 1570 fathoms, and south of Australia, 2600 fathoms ; 
at two points in the South Pacific, 1375 and 1425 fathoms respectively, and at three in 
the North Pacific, 2050 to 2900 fathoms. 
Reophax membranacea, H. B. Brady (PI. XXXII. figs. 1-4). 
Reophax membranacea, Brady, 1879, Quart. Journ. Mier. Sci., vol. xix., N. S., p. 53, pi. iv. 
fig- 9. 
Test long, slender, tapering, arcuate or nearly straight ; consisting of several (5 to 
10) subcylindrical or elliptical segments joined end to end. Walls thin, chitinous, beset 
with minute adherent sand-grains ; often transversely wrinkled. Length, T ^th inch 
(1*4 mm.). 
In one or two deep soundings from very muddy bottoms minute moniliform Lituolce 
have been found, possessing a delicate investment of light brown tint and nearly trans- 
parent. The test is only partially soluble in weak acids, and it appears to consist of 
calcareous and chitinous matter, with sometimes a few very minute, adherent or embedded 
siliceous sand-grains. The mineral constituents exist in sufficient quantity to effervesce 
slightly with an acid, and to render the test brittle rather than flexible after it is dried ; 
but the surface is wrinkled transversely, in a manner strongly suggestive of a membrane 
covering a soft or plastic mass. Referring to the drawings of the species in PI. XXXII. — 
figs. 1 and 2 represent specimens in their natural condition, mounted dry ; fig. 4 a 
specimen mounted in Canada balsam, viewed by transmitted light ; and fig. 3 a test 
that has been treated with dilute acid, mounted in balsam. Unfortunately the species is 
