FRESHWATER RHIZOPODS AND HELIOZOA. 337 
and in each it is enveloped in a thick coat of apparently mucous 
material. This external envelope is very delicate, and in the 
specimens I observed was only rendered visible by small bacteria 
which adhered to its outer surface. The pseudopodia in the 
animals described by Schulze and Greeff are of the same type, 
and, moreover, this type is somewhat peculiar. Some, but not 
all, of the pseudopodia are branched, and to my mind this not 
only indicates a close affinity between the above-mentioned 
Heliozoa, but is quite sufficient to separate Greeff’s Heliophrys 
from Archer’s Heterophrys. 
The specimens observed from Lincolnshire possessed one 
nucleus, and this was in a somewhat excentric position. No 
contractile vacuoles were observed, but I have no reason to 
believe that they were absent. 
Gen. Hererorpurys, Archer. 
60. HETEROPHRYS MYRIAPODA, Archer, in Qu. Jour. Mier. Sct. 
1869, n.s. ix. p. 267, t. xvii. f. 4. 
Llyn-y-ewm-ffynon, N. Wales. Diameter of body about 27 p. 
The forms observed were somewhat small, but agreed in all 
respects with Archer’s description and figure. 
61. HeTEROPHRYS RADIATA, sp.n. (PI. 30. fig. 34.) 
Body small, spherical, dark grey in colour, protoplasm densely 
filled with granules of variable size. Nucleus single, situated in 
an excentric position. No vacuoles observed. Outer coat of 
gelatinous material quite colourless, almost as thick as the 
diameter of the body, with a finely fimbriated outer surface. 
Pseudopodia numerous, long and delicate, with numerous 
scattered granules along their length. 
Diameter of body 21 p, with outer coat 53 pw; length of 
pseudopodia about 43 p. 
Epping Forest, Essex, in ponds. 
This species of Heterophrys is nearest the one described by 
Hertwig and Lesser (in Archiv fiir mikr. Anat. 1874, x. Suppl. 
p. 215, t. v. f. 3) as H. spinifera ; but it is distinguished from the 
latter by the larger body and the much less fimbriated outer 
covering. The pseudopodia are also much more numerous, and 
in proportion to the size of the body are considerably shorter. 
trom H. myriapoda, Archer, it is distinguished by its smaller 
