140 



PROF. ST. GEORGE MIVART ON 



sbaped, or in the form of flattened disks, and such disks may be 

 here and there enlarged by having wide arm-like productions. 



The sarcode is a homogeneous protoplasmic substance contain- 

 ing granules. A chitinous membrane divides it, as before said, 

 into an intra- and an extracapsular scarcode, these parts being 

 directly continuous through minute pores which perforate the 

 membranous capsule. The sarcode may be extremely fluid, as in 

 Collo splicer a ^ or relatively firm, as in Acanthometra. 



In most solitary forms the capsule is very large relatively to 

 the w^hole mass, the extracapsular sarcode being relatively scanty. 

 In some forms, however, the reverse is so much the case that the 

 diameter of the capsule may be but about one fifth of the whole 

 organism, as is the case in Thalassicolla. In the compound forms 

 (colonies) the capsules appear as small spheres scattered through 

 the relatively large mass of extracapsular sarcode and gelatinous 

 investment. 



The size of the capsule may vary from about 2 millims. (Thalas- 

 solampe and Physematium) to 0*025 millim. {ZygostepJianus). 



It is formed of a relatively strong membrane perforated by very 

 numerous minute apertures or pores, and sometimes marked by 

 lines dividing its surface into irregular polygonal segments, as in 

 Thalassicolla. 



Its shape is mostly spheroidal ; but this may vary with the 

 shape of the entire organism. It may also be vertically elongated, 

 with terminal or median enlargements, or both ; or (as in some 



Fig. 2. 



Euoecry^halm Schiilfzei, showing the lobod central pseudopodia and capsule 

 and the oil-globules within them. (After Kolliker.) 



