the Seed in the Alsinoideae. 
45 
contain isolated starch grains which would not be traceable in cells 
containing proteid material. This wing is differentiated while the embryo 
is still in the suspensor stage. 
The primary suspensor cell in both Spergula arvensis and Spergidaria 
rubra shows a well-marked reduction in size. This is so apparent that 
Hegelmaier (10) speaks of the small celled suspensor of Spergula arvensis . 
Schleiden and Vogel (2) figure a row of undifferentiated cells of Spergula 
pentandra. This species was not available for examination in the present 
case, but in both the species investigated the primary cell is still con- 
siderably differentiated in size and contents from the succeeding ones of 
the row. The suspensor in the Sperguleae has a tendency to become 
more massive, as the cells composing it divide again vertically, thus 
forming a double row of cells. The primary cell does not divide again. 
The air spaces in the angles of the walls of the cells occurring just above 
the ‘ aerenchyma ’ layers are very pronounced in the mature and germinat- 
ing seed of Spergula arvensis. 
The synergidae are small and short in Spergida arvensis and long 
and narrow in Spergidaria rubra. 
Antipodals are well marked in both. 
Alsineae. The synergidae fall into two types — 
1 . Long, with large nuclei, which attain their greatest development in 
Arenaria trinervia (Fig. 8 , syn.) and Stellar ia media. 
2. And a shorter type with inconspicuous nuclei, which occurs in 
Sagina procumbens, S. ape tala, and St ell aria uliginosa. 
Antipodals are not always present or at least are not sufficiently 
obvious to be observed. They are well seen in Sagina procumbens and 
•S*. apetala , and in Stellar ia media. In other species though clearly shown 
in the progressive free nuclear divisions of the embryo-sac nucleus, they 
were not so apparent at a later stage. 
Definitive Nucleus. In all species, with the exception of Stellaria 
media , there is no actual contact between the nuclear membranes of the 
oosphere and definitive nucleus, some cytoplasm always separates them 
(Fig. 8 , oos. and d. ni). 
Basal suspensor cell. In Cerastium and Stellaria species this cell is 
very large. In Sagina apetala and S. procumbens it is smaller. It can be 
recognized in all the species before the division of the oospore, and the apex, 
though only prolonged as an haustorium in Stellaria media , shows the same 
marked differentiation in contents which stain darker and more homogene- 
ously in that region. 
Persistent pollen-tube. Is characteristic for all species except Stellaria 
media , and is especially well seen in Sagina apetala and .S'. procumbens , 
Cerastium species, and Stellaria aquatica (Fig. 13 ). The pollen-tube 
twists on itself before it enters the synergidae, forming a plug on the apex 
