REPORT ON THE EORAMINIFERA. 
227 
favourable conditions one such opening is found near each end of the chamberlet; and 
as a section only shows one side of the cavity, there is probably a lateral orifice 
communicating with each contiguous chamberlet. 
The analogy of the individual layers of Keramosphcera to the superficial layers of a 
compound Orbitolite has been adduced in order to explain some otherwise obscure points 
in the structure of the test. It is, however, by no means complete, for in Orbitolites the 
superficial chamberlets are connected with each other by stoloniferous tubes, but have no 
communication with the exterior, except through the apertures on the peripheral edge of 
the test. In Keramosphcera, on the other hand, the layer of chamberlets is continuous 
over the entire sphere, and in the absence of an exposed peripheral edge the necessary 
communication with the exterior is afforded by the superficial orifices of the individual 
chamberlets. The only other abnormal character which requires notice is the irregularity 
of the outline of the chamberlets. But this anomaly is apparent rather than real, for 
though the complex types of porcellanous Foraminifera commonly display great symmetry 
and regularity in the contour and disposition of their various parts, this is by no means 
an invariable feature of the group. The labyrinthic subdivisions of the chamberlets in 
the complex Alveolince furnish a case in point; and in one porcellanous genus, Nubecularia, 
irregularity is the rule rather than the exception. 
The two specimens of Keramosphcera murrayi were found by Mr. Murray in the 
siliceous diatom ooze from Station 15 7, a locality, roughly speaking, about twenty 
degrees south of the south-western corner of Australia, depth 1950 fathoms. 
Family III. ASTRORHXZID^E. 
Our acquaintance with the large arenaceous Rhizopods which constitute the family 
Astrorhizida is almost entirely derived from the operations of the various recent 
expeditions, organised and equipped by Government for the exploration of the deep sea. 
The genus Astrorhiza was described by Sandahl in 1857, and a closely allied type, 
Dendrophrya by Strethill Wright in 1861, but these are amongst the few forms that 
inhabit comparatively shallow water, and it is to deep-sea dredging in the North Atlantic 
during the past twelve or fourteen years that we owe the discovery of nearly all the 
more important members of the group. 
Except in the case of a few species, of which the living animal has been to some 
extent studied, our knowledge of the life-history and organisation of the Astrorhizida is 
still very imperfect ; and it is by the external form of the test and its minute structure, 
rather than by the characters of the animal inhabiting it, that the various types are 
recognised. Even concerning the test itself — the selection of material and the means 
employed for its incorporation — we are only at the threshold of research ; but deficient 
