21,1 Shaw: Merrillosphaera 93 
Anterior, 20 »; equatorial, 13 »; posterior, 15 #3; mean, about 
15 ». Estimated number of cells, 5,300. Somatic protoplasts, 
about 5to6,. A thick middle lamella of the somatic cells shows 
in a surface view, even under the low power. The embryos, 
about 90 p, are closed or closing. The phialopores are directed 
outward, and a side view of one embryo shows the lobes around 
the stellate opening bent outward and tipped with large cells. 
The inner ellipsoidal membrane, or core boundary, of the coeno- 
bium is 380 by 358 y», the zone between it and the outer limit 
of the coenobium being 115 » in front and 130 » behind. The 
inner lamella of the embryo capsule delimits the space about 
each embryo, but the outer lamella does not show. 
Specimen 4.—An asexual coenobium with eight embryos, 565 
by 593 ». Spacing! of cells: Anterior, 20 »; equatorial, 15 p»; 
posterior, 13 »; estimated mean, 15». Number, 5,300. Embryos 
85 to 95 y», closing and closed, with gonidia protruding beyond 
the surface. Lobes about the phialopore bent outward in one 
embryo and bearing larger cells. Only the inner lamella of the 
embryo capsules is visible. 
Specimen 5.—An asexual coenobium with six embryos and 
four gonidia. Oblique view. 562 by 590 ». Spacing of cells, 
10 to 18 (mean 11) pp. Number, 9,800. Embryos about 80 » 
each, with protruding gonidia. Two of the gonidia of the parent, 
each about 64 » in diameter, form a posterior pair; while the 
two others, with diameters of 68 and 70 p», respectively, form 
a subposterior pair. 
FEMALE COENOBIA 
An asexual coenobium (specimen 6) with eight female 
daughters, which are distributed like the embryos in the type 
specimen, is shown in Plate 1, fig. 3. This specimen is of the 
same collection as the type specimen, but of a batch fixed one 
day later; that is, two days after collection. It is in a picro- 
nigrosin preparation mounted in glycerine; it was photographed 
in 1916, and was still in good condition in 1919. The coenobium 
measures 590 by 643 ». The thickness of the specimen measured 
about 250 ». Near by is a glass rodlet 265 » thick, which was 
used to support the cover glass. The somatic protoplasts are 
about 5.3 to 5.9 » wide. Their intercentral distances respectively 
are approximately these: Anterior, 21 »; equatorial, 14 »; pos- 
terior, 17 »; and mean, considering the relative extent of the 
different areas, 16 ». This gives the estimate of the number 
of cells, 5,250. The daughters all contain reproductive cells, 
which are more numerous and smaller than gonidia would be at 
