Seedling Structure of certain Centrospermae, 183 
between S also la Kali, S. Soda , vS. vermicidata , Suae da, Chenopodium , Blitum , 
Roubiera, and Beta. He concludes that the transition in the Chenopodiaceae 
takes place at different levels of thehypocotyl : at the lower end in A triplex, 
Salsola, and Suaeda ; slightly below the level of the insertion of the cotyle- 
dons in Beta and Spinachia ; whilst, finally, in Blitum and Chenopodium it 
takes place in an intermediate position. 
CYCLOLOBEAE. 
Beta brasiliensis, ?, B. chilensis , Hort., B. hortensis , Mill., and B. vid- 
garis , Moq. The details of the transition in these plants are like those of 
Amaranthus caudatus, the only differences being that in Beta a short cotyle- 
donary tube is formed and there is no marked delay in the fusion of the 
phloem-masses in the hypocotyl. 
Chenopodium ambrosoides , L., C. Atriplicis , L., C. Bonus-Henricus , L., 
C. Botrys , L., C. calulatum , ?, C. capitatum, Aschers, and C. scop avium, L., 
all resemble Amaranthus and Beta. A short cotyledonary tube occurs in 
C. Bonus-Henricus , C. capitatum, and C. scoparium. The bifurcation of the 
central cotyledonary strand takes place well within the blade of the seed- 
leaf, but in no case is the protoxylem entirely isolated as in Amaranthus 
sylvestris. The V-shaped bundle is accompanied downwards by two laterals, 
and their union occurs at different levels : in C. ambrosoides and C. Botrys 
this coalescence takes place at a level well above the cotyledonary node; in 
C. Atriplicis, C. Bonus-Henricus, C. calidatum, and C. capitatum the junction 
is at, or just above, the cotyledonary node ; finally, C. scoparium is remark- 
able in the fact that the laterals make no junction with the central strand, 
but come to an end. 
It may also be remarked that there is no particular delay in the fusion 
of the groups of phloem-elements in the axis, as obtains in Amaranthus. 
Atriplex liastata , L., has its transition-characters in common with many 
species of Amaranthus, Gomphrena, &c. The main seed-leaf-bundle bifur- 
cates at a relatively high level, and the separation of the two halves is so 
complete that the protoxylem appears in an isolated position at a level above 
the cotyledonary node. There is thus a close resemblance to Amaranthus 
sylvestris , the only difference, of degree rather than kind, in this respect 
being that in the last-named plant this isolation takes place at a much 
higher level. A minor feature of difference is that the main bundle may be 
accompanied in its passage down the petiole by two or three laterals on 
each side, not two as is the case in all the foregoing plants. These lateral 
strands join on to the adjacent halves of the divided central bundle at the 
cotyledonary node, and sometimes even in the top of the hypocotyl, 
a feature of resemblance to some of the foregoing plants, Gomphrena haageana 
for instance. Again, as in many species of Amaranthus, there is a marked 
delay in the union of the corresponding pairs of phloem-masses within the 
