Seedling Structure of Gy mno sperms. II. 201 
rotated in pairs so that a pentarch root resulted. During these changes 
resin canals developed opposite the four remaining protoxylem groups in 
exactly the same way as in P. Pine a. 
Pinus halepensis , Mill., closely resembles P. Gerardiana ; there are, 
however, more whole-cotyledons in P. halepensis, and, further, the bifurca- 
tion and rotation of the bundles of these whole-cotyledons may take place 
at a higher level. 
Pinus Coulteri , D. Don. 
Series A. A well-marked tube was formed by the thirteen cotyledons r , 
the bundles of eleven of which were endarch and collateral throughout ; the 
remaining two showed bifurcation of the phloem and rotation of the xylem 
in different degrees, before an entry into the axis had been made, a feature 
not observed in any of the foregoing plants. Within the hypocotyl the 
phloem of another bundle quickly divided and, at the same time, 
the protoxylem commenced to take up its exarch position. Thus, there 
were three bundles which underwent bifurcation of the phloem, and 
a certain amount of rotation of the xylem : generally, these three bundles 
would form three poles of the root; but, in this particular case, two only of 
these particular strands behaved as would have been expected, the third, in 
the transition region, behaved as a half-cotyledon and with an adjoining 
bundle formed one pole of the root. The other strands acted as the bundles 
of either half- or subsidiary-cotyledons. 
Series B. A similar phenomenon occurred in this seedling. There 
were eleven cotyledons forming a tube as before ; and the bundle of one 
seed-leaf showed rotation of the xylem and bifurcation of the phloem while 
still contained within the cotyledon. Within the hypocotyl four other 
strands showed a similar rearrangement ; of these one exhibited the re- 
distribution of vascular elements very fully, but the change came to nothing, 
the bundle being doomed to play the insignificant role of a subsidiary 
cotyledon. 
The theoretical importance of these facts will be dealt with, when like 
occurrences have been described in other plants. 
Pinus canariensis , C. Sm. One plant only was available for examina- 
tion, which differed in no important feature from P. Coulteri. One bundle 
only showed signs of the rearrangement of the vascular elements while the 
strand was still contained within the seed-leaf, and no trace showed the 
curious change especially mentioned as occurring in P. Coulteri. There were 
nine seed-leaves 1 2 , of which two were whole-cotyledons, three were sub- 
sidiary-, and four were half-cotyledons. The root was tetrarch. 
1 According to Masters (loc. cit.), 10-14 cotyledons occur. 
2 According to Masters (loc. cit.), 6-8 cotyledons. 
