220 THE ATLANTIC. (CHAP. Il. 
prominent. This capsule is, however, absent, or, at all events, 
exists in a very modified form, in the more typical groups. 
The body may be entirely naked, a mere sphere of sarcode 
giving off pseudopodia; or it may have a more or less fully-de- 
veloped skeleton; sometimes in the form of separate horny or 
siliceous spicules, very like the spicules of sponges, disposed in 
an irregular net-work over the surface. In one interesting form 
(Fig. 51), which is especially abundant on the surface in some 
parts of the Pacific, minute echinated calcareous spheres, look- 
ing in outline like the rowels of spurs, are scattered irregularly 
in a fine gelatinous envelope which incloses the granular sarcode 
and oil-cells. We were familiar with these calcareous bodies in 
the soundings, but we had always taken them for the spicules 
of a Holothurian, which they much resemble. In the two groups 
fi 
i m 
My y ', 
b \} i 4 
WA 1 Yi 
%, WH i, 
‘ GAs ae! ij Jp 
Ni 
" 
fa , 
Me oy % | 
4,4 h 'h, 
i (pe 
ee 
, ‘ny ue 
"ni, 
Fia. 51.—Calearomma* calcarea, Wyvitte Tomson. With the pseudopodia contracted. 
From the surface. Two hundred times the natural size. 
* Calcar, a spur. 
