162 BOTANICAL GAZETTE [MARCH 
A portion of the cluster more highly magnified is shown in fig. Zo. 
Fig. 5 shows the appearance of this “false’’ ray in transverse section. 
This structure led to the suspicion that the large rays of the existent 
oaks might be derived from the so-called “false rays” of the lower 
‘Cupuliferae; that is, that the former have been ‘‘built up” by the 
aggregation and fusion of the small rays. ‘The Miocene fossil would 
then represent a comparatively recent ancestral condition in ray 
structure. Two American species of Quercinium from Tertiary 
deposits in the Yellowstone National Park, Quercinium Knowltonti 
Felix' and Q. lamarense Knowlton,? have rays which seem, from 
the figures and descriptions, to be very much like those of the fossil 
here figured. The question then arose whether the seedlings of our 
living species of Quercus do not present some evidence as to the origin - 
of the larger rays in living oaks, inasmuch as the seedling is known 
to be a seat of ancestral characters. The investigation of a number of 
North American species showed that we have in the oaks a good 
example of seedling recapitulation. 
The oaks, from paleobotanical evidence, seem to have descended 
from ancestors that resembled the living chestnuts. There is much 
similarity in the structure of the reproductive organs, and in the type 
of leaf shape of the oldest oaks, and of the chestnuts. Confirmatory 
evidence is presented by the seedlings of some of our living oaks; 
especially worthy of notice is the fact that the first rays formed are 
all of the type which is found throughout chestnut wood. 
In respect to ray structure in the seedlings, the species examined 
fall into two groups, corresponding with the subgenera Lepido- 
balanus (white oaks), and Erythrobalanus (red or black oaks). 
The seedlings of the black oaks that were examined by the writer 
(Q. rubra L., Q. velutina Lam., Q.coccinea Moench., and Q. ilicijolia 
Wang.) all show a ray structure very much like that of the gold 
gravel oak above described. In the early annual rings, from the 
first or third to about the fifteenth, a progressive compounding, that 
is grouping and fusion, of the linear rays occurs, with the final pro- 
duction, after the considerable period of compounding, of a single, 
' Ferx, J., Untersuchung iiber fossile Hélzer. Zeit. Deutsch. Geol. Gesells- 
—250. pl. 6. 1806. 
2 Knowtton, F. H., Geology of the Yellowstone National Park. Part 11. U. S- 
Geol. Survey. p. 771. pls. 118, 120, I2I. 1899. 
