40 
The Queensland Naturalist 
May, 1943 
the best brain. At birth it is about one-fifth its ultimate 
size, and it is thought that it is improved by education. 
A light supper was served at the conclusion of the 
meeting, the final one for the year. 
THE TREE-FERNS OF QUEENSLAND. 
By D. A. Goy, Botanic Museum and Herbarium, 
Brisbane. 
Tree-ferns contribute so largely to the beauty of our 
rain forests (scrubs or jungles) both in Northern and 
Southern Queensland, that an account of the different 
kinds accompanied by simple keys for their identifica- 
tion, should be of interest. In preparing such keys and 
description^ the use of some technical terms is unavoid- 
able. The following few notes are therefore offered to 
assist in the interpretation of the key characters. 
While ordinary flowering plants reproduce by means 
of seeds, ferns produce millions of tiny spores for this 
purpose. The minute powdery spores are enclosed in 
elaborately constructed cases or sporangia. These spore 
cases are clustered together in small masses of various 
shapes and in different positions on the frond, usually 
on the under surface. Each individual cluster is called a 
sorus. Sori are often, though not always, protected by 
some sort of covering. Sometimes protection is afforded 
simply by the margin or part of the margin of the frond 
bending back over the sorus. Again, there are many kinds 
of coverings distinct from the ordinary substance of the 
frond, some of which are persistent on the sorus after 
maturity, others shrivelling and falling off at an early 
stage. The coverings or indusia open in various ways 
when the spores are mature. All these facts — the shape 
of the sorus, its position, the nature of the indusium, if 
any, and the method of attachment and opening of the 
indusium — come into consideration in the classification of 
ferns. 
One of the characteristics of the majority of ferns 
which gives these plants their delicate lacy beauty, is the 
compound nature of the fronds. That is, the frond usually 
