T915] BURLINGAME—ARAUCARIANS 99 
fossil. Their presence in the older araucarian types, consequently, 
is one more piece of evidence in favor of the derivation of the arau- 
carian tribe from abietineous ancestors.” (7) The author reiter- 
ates his belief in the compound nature of the ovulate cone and in its 
essential unity throughout the group. He says, “‘it is perfectly 
clear that not only in the more primitive species of the living genus 
Araucaria, but also in the cones of the mesozoic representatives, the 
araucarian female cone, like that of the other tribes of conifers, 
was originally composed of cone scales with a double system of 
bundles, independently emanating from the cone axis and of inverse 
orientation.” (8) In regard to the male gametophyte he says, “‘cer- 
tainly we should not expect to find the primitive type of pollen 
tube formation in a group in which the pollen no longer reaches 
the apex of the ovule,” and ‘‘the peculiar method of germination 
of the pollen is an unmistakable stigma of aberration.” ‘‘The 
contents of the pollen tube likewise vouch for the highly specialized 
condition of the Araucarineae. Here the two prothallial cells com- 
mon to the Abietineae and the equally ancient Ginkgoales become 
proliferated into a large number, doubtless in correlation with 
the extreme length and meandering course of the pollen tube. 
Moreover, the absence of a stalk cell in connection with the setting 
off of the body cell, which gives rise to the two sperm cells, is a clear 
and outstanding feature of aberrancy.’’ These views are in a 
measure a modified restatement of those stated by JEFFREY and 
CHRYSLER in 1907 (36). JEFFREY is equally convinced that the 
female gametophyte is not primitive but aberrant. 
In a very complete study of Agathis (19) Eames has reached 
conclusions closely paralleling those of JEFFREY in regard to the 
specialization of the gametophytes and the interpretation of the 
structure of the ovulate cone of the araucarians. An interesting 
and important feature of this investigation is the very complete 
reduction series which he has worked out in the supposed develop- 
ment of the apparently simple scales of Agathis. Beginning with 
Arthrotaxis cupressoides with a completely double vascular supply, 
he traces the gradual fusion of the independent bundles through 
other species of the same genus, Cunninghamia sinensis, and 
finally reaches the condition found in Agathis. He also points out 
