ON THE DEVELOPMENT OF LICHENOPORA VERRUCARIA. 73 
becomes stocked with numerous larve. The other zocecia of 
the colony remain, for the most part, unfertile, although many 
of them produce spermatozoa. It is clear that they have the 
function, not only ef feeding themselves, but also of providing 
nutritive material at the expense of which the ovicell and its 
brood of larvee may develop. The restriction of the female 
reproductive function to a single individual, or at least to a 
very small number of individuals of the colony, is by no means 
in accordance with what is known of other colonial animals. 
The remarkable nature of the phenomenon will be most clearly 
realised when it is understood that the fertile zocecium is 
usually one of the two “ blastozoites,” which are first formed 
by budding from the “‘ oozoite.”’ } 
My material was collected in Norway at Lervik, in Stordo, 
and at Godosund, off the north coast of Tysnaes6, during the 
end of June and the beginning of July. At that time of the 
year there is no difficulty in collecting an indefinite number of 
colonies from the earliest stages immediately after metamor- 
phosis to the fully developed condition. The entire colonies 
were preserved for the most part in corrosive sublimate, to 
which, in some cases, a few drops of nitric acid and of acetic 
acid were added. ‘The internal details were studied prin- 
cipally from sections, which were prepared for me by my wife, 
but to some extent in entire colonies stained without decal- 
cification. The external features were investigated in dry 
mounts and in Canada-balsam preparations, whether stained 
or unstained. 
Owing to its discoidal or flattened form, the colony will 
obviously tend to rest on one of its flattened surfaces when it 
is mounted. In order to examine certain features which can 
only be made out when the colony is looked at edgeways, it is 
necessary to make some special arrangement. This has been 
successfully accomplished by folding a piece of black paper into 
* These terms, first introduced by Lacaze-Duthiers, have been appro- 
priately employed by Prouho (18) in describing the colonies of Polyzoa. ‘The 
oozoite is the individual developed from an egg, i. e. the metamorphosed 
larva or primary zoccium of the colony. The blastozoite is an individual 
which has been formed as a bud. 
