ANATOMY AND PHYSIOLOGY OP THE POEAMINIPEEA. 175 
circumstances, Carpenteria establislies such a connection, 
even though the specular skeleton proves to have no organic 
connection with it. 
The only type whose gTowth remains to be noticed is that 
of the Miliolae — a group of shells exhibiting in a strongly 
marked form the procelainous texture, and which have also 
an internal structure peculiarly their own. They are virtually 
long and more or less flattened tubes, wound round an oblong 
central axis, becoming* much constricted where the tube 
bends round each extremity of the shell, or at each half-turn. 
Hence each convolution is longer than its predecessor. Some- 
times these successive convolutious are arranged concentrically 
on one plane (Spiroloculina, flg. 13), at others they are added 
in a revolving one (Triloculina, flg. 14), an arrangement to 
which French naturalists have given the name of ijelotonee, 
from its resemblance to the process of winding a thread upon 
an oblong ball of cotton. The Miliol^ have no foramina in 
their shell- walls for the transmission of pseudopodia ; but this 
lack is compensated for by the large size of the terminal 
septal, or, as it is sometimes termed, oral aperture. 
As I have already remarked, all the calcareous and arena- 
ceous forms of shell that I have just described are to be 
regarded in the same physiological light as the calcareous 
and horny skeletons of sponges and corals. They are secreted 
by the soft gelatinous animal substance to which the name 
of Sarcode has been given, and to the nature of which attention 
may now be directed. 
Sarcode is a translucent protoplasmic substance, having 
some condition of albumen as its base, but containing oil- 
globules in addition. It is remarkably plastic or ductile; 
capable of being drawn out into slender threads (figs. 1, 2, 3), 
which readily merge again into a continuous mass when they 
come into mutual contact. These pseudopodia, as the threads 
are termed, correspond very closely in this and other respects 
with the radiating protoplasmic bands seen in the body of the 
Hoctiluca, which causes the sea waves to sparkle with phos- 
phoric light, and with the curious radiating masses occurring 
in the more highly organized Rotifera. In the latter cases, 
the substance would appear to be a part of the protoplasm 
of the original ovum not used up in the formation of the 
organism, a circumstance that throws light upon the organiza- 
tion of the Foraminifera and their allies. Sarcode, therefore, is 
the lowest form of animal substance, approaching nearer to 
the contents of an ovum prior to their reorganization into 
tissues than any other known material. In the living Forami- 
nifera sarcode is usually of a yellowish, but sometimes of a 
red colour, the tint being' deepest in the older and m.cre 
