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Hill and de Fraine . — On the 
of their respective cotyledons, but they divide completely into two, leaving 
protoxylem elements isolated between them, a feature which is characteristic 
of Phytolacca, Allionia, Mirabilis , and other Nyctaginaceae ; also it occurs in 
some species of Lupinus and Dahlia. A minor point to be remarked upon 
in Amaranthus sylvestris is that the union of the laterals with the central 
bundles of the cotyledons is effected at a much higher level than in 
A. caudatus , &c. 
Pupalia purpurea , unlike any of the foregoing species of Amaran - 
thus , does not show an early inauguration of the transition phenomena ; in 
fact the bundle from each cotyledon enters the axis in an undivided endarch 
condition, all the changes leading to the formation of a diarch root-structure 
taking place rapidly in the upper part of the hypocotyl. 
GOMPHRENOIDEAE. 
Gomphrena haageana, Klotzsch, resembles Amaranthus sylvestris in the 
division of the central cotyledonary bundles and isolation of protoxylem 
elements in the blade of the cotyledon. A feature of difference is found in 
the fact that one of the laterals may delay fusion with the adjacent half of 
the central strand until the upper region of the hypocotyl is reached. 
Gomphrena globosa, L., is, in essentials, identical with G. haageana \ the 
isolation of the protoxylem, however, is not so well marked as in the latter 
plant. In both species a cotyledonary tube is formed, a point of difference 
from Amaranthus and Celosia. 
CHENOPODIACEAE. 
The anatomy of the seedlings of this Order has formed the subject of 
investigations by previous authors. Van Tieghem 1 has remarked upon the 
occurrence of diarchy in the primary roots of Beta vulgaris , Spinachia 
oleracea , and A triplex hortensis. 
Gerard 2 has shown that the transition of A trip lex hastata follows that 
of type 3, and that it is not by any means rapid. 
The work of Dangeard 3 in this connexion has already been alluded to ; 
it may, however, be further remarked that he considers that the venation of 
the cotyledons has an important bearing on the primary root-structure and 
concludes that the seed-leaves with pinnate venation have a diarch root, 
whilst those with a palmate venation have a tetrarch root-structure. 
Fron 4 has made the, hitherto, most extensive study of the seedling 
anatomy of this Natural Order, and points out that the structure of Atriplex 
hastata is typical for the genus. He also draws attention to the similarity 
1 Van Tieghem : Recherches sur la symetrie de structure des plantes vasculaires. Ann. Sci. 
Nat., Bot., ser. 5, t. xiii, 1870. 2 loc. cit. loc. cit. 
4 Fron: Recherches anatomiques sur la racine et la tige des Chenopodiac^es. Ann. Sci. Nat., 
Bot., s< 5 r. 8, t. ix, 1899. 
