28 Gibbs. — Notes on the Development and Structure of 
C. perfoliatunii L., Sagina apetala, L., 5 . procumbens , L., 
Moehringia , sp. 
2. Sperguleae. 
Spergula arvensis , L., and id. var. sativa (Boenn), Spergularia 
rubra , Pers. 
B. From the definitive nucleus stage as far as the maturation of 
the seed. 
1. Alsineae. 
Stellaria Holostea , L., 5 . media , Cyr., 5 . aquatic a, Scop., Cerastium 
glomeratum , ThuilL, £ 7 . perfoliatmn , L., Sagina apetala , L., 
At sine trmervia , L. 
2. Sperguleae. 
Spergula arvensis , L. 
C. Germination of the seed. 
1. Alsineae. 
Stellaria Holostea , L., A. aquatica , Scop., Cerastium perfoliatum , 
L., Alsine laricifolia , Wahlenb., A. fasciculata, M. Koch. 
2. Sperguleae. 
Spergula arvensis. L., and id. var. sativa (Boenn), Spergularia 
salina , Presl. 
Historical. 
The results of former work on the group are as follows 
Grew ( 1 ) in 1682 figures the seeds of Spergula and chickweed, describ- 
ing the former as ‘ spherick in shape with a knobbed surface and membranous 
Rim in/ and the latter as kidney-shaped. 
Schleiden and Vogel ( 2 ) in 1839, in a paper on ‘Albumen’ first 
distinguished between ‘ perispermium ’ or storage tissue derived from 
the nucellus and ‘ endospermium ’ or tissue derived from the embryo-sac. 
They give a very good figure of Spergula pentandra with the small celled 
suspensor which characterizes the Sperguleae, and in a series show starch 
storage tissue limited to the central mass of the nucellus, which alone 
persists as the embryo matures. 
Meyen ( 3 ), 1841, working on Stellaria media , noticed the elongation 
of the suspensor beyond the embryo-sac peculiar to this species. He 
figures the characteristic twist of the pollen-tube, where it adheres to the 
apex of the embryo-sac. Following Schleiden, he interprets it as the 
beginning of the ‘ vesicule embryonnaire ’ which he describes as developing 
first into the apical portion of the suspensor and ultimately into the suspensor 
and embryo. He considered, that from its size, the suspensor must absorb 
food material for the embryo. 
Unger ( 4 ), 1855, figures the style of Stellaria media , with a pollen- 
