322 Saxton . — Contributions to the Life-history of 
Field Notes, &c. 
The plants of Actinostrobus pyramidalis growing in the neighbourhood 
of Perth are seldom above 10 feet high, and have a very similar habit to 
small trees of Callitris. The persistence of the old cones is a characteristic 
feature ; Dr. Morrison informs me that they remain attached to the stems 
for several years before shedding their seeds, on the main stem and two or 
three grades of branches. 
It seems probable that female cones, and perhaps a few male cones, 
may make their appearance at various seasons of the year, but the normal 
crop of young cones appears about May or June. Pollination takes place 
from June to August, the pollen being shed from one tree after another, 
in an apparently gradual succession. From the development of the ovules, 
however, it seems fairly certain that effective pollination only occurs about 
the first half of July. Dr. Morrison records the very interesting observation 
that a drop of fluid may be seen extruded from the open micropyle of the 
young ovules, in which doubtless the pollen-grains are caught and subse- 
quently withdrawn on to the nucellus. Of the various devices facilitating 
pollination in Conifers, this would appear from the rather scanty records to 
be the commonest. The pollination drop has also recently been observed 
by the writer in Widdringtonia. In Callitris , ovules young enough to be 
likely to show this phenomenon have not at present been seen. 
Approximately three months elapse between pollination and fertiliza- 
tion, the latter occurring about the second week in October. Fertilization 
is not so nearly simultaneous in different ovules as it is in Pinns and some 
other genera, but probably does not vary more than about a week, on either 
side of the average. It is interesting to note that although the winter 
seasons of 1910 and 1911 were very different, especially as regards rainfall, 
the average date of fertilization did not differ appreciably, collections 
covering that event having been made on October 12, 1910, and 
October 9, 19T1. 
Unlike some Conifers, in which the cones are often almost full grown at 
the time of fertilization, Actinostrobus cones are only about two-thirds of 
their mature size at that time. They attain their full size about a month 
later, when they can only be distinguished from previous years’ cones by 
their green colour. 
The female cones are terminal on very short branchlets, these being 
borne in the axils of foliage leaves near the base of a young branch. At 
the time when pollination takes place the cone scales are not widely 
spreading as they are in other Callitrineae, but are evidently prevented from 
diverging by the closely appressed barren scales of the cone. After pollina- 
tion the fertile scales rapidly increase in size, and grow together over the 
top of the cone in the manner recently described for Callitris by Baker and 
