No.1.] BUDDING IN GOODSIRIA AND PEROPHORA. 213 
acquired independently by different species and at different 
times. 
Now it is certain, both on theoretical and on observational 
grounds, that there would always be a tendency, and a strong 
one, for all the germ layers to participate in the production of 
the bud ; and should they be found to do so in particular cases 
where the conditions are such as to cause, according to my 
idea, one or the other of the layers to be excluded from the 
process, this might be due to the fact that such exclusion had 
not yet been fully effected because of the comparatively recent 
acquisition of the property of budding. 
2. ON THE QUESTION OF DIFFERENT TyYpPEs OF BUDDING 
AMONG TUNICATES. 
Having now before us the facts concerning the budding in 
these two genera, we must compare them in order to see 
whether the differences must be regarded as fundamental, or 
whether the mode of development in the two cases is more 
probably a modification of a common type. 
The first point to be considered is the relation of the bud to 
its parent. Various authors have expressed more or less posi- 
tively the view that the two modes of bud origin represented 
by Perophora and Goodsiria, t.e. the stolonic and the pallial, 
have been derived from a common primitive type. Garstang 
(95) is the most recent of these, and he has adopted this inter- 
pretation apparently with considerable confidence. 
It is interesting to notice that the relation between the 
blastozooids of a colony in these two genera may be viewed in 
such a way as to give the appearance of a rather close resem- 
blance. 
If we disregard the embryozooid from which the colony has 
sprung in each case, and fix our attention upon the adult 
blastozooids only, we may reduce the entire colony to a series 
of individuals connected with one another by their peribran- 
chial sacs through the stolonic septum, or cloison. 
This is evident enough in Perophora, where it is essentially 
the actual state of things ; the only modification of it being 
