No.1.] BUDDING IN GOODSIRIA AND PEROPHORA. 187 
B. PEROPHORA ANNECTENS, RITTER. 
1. INTRODUCTORY. MATERIAL. ‘TECHNIQUE. 
I have described this species in detail in a former paper ('94), 
and consequently am relieved from doing so here. One point 
only concerning it I must speak of briefly. In the description 
referred to, I have said in substance that the species includes 
at one extreme colonies in which the zooids are quite as 
distinct from one another as they are in P. Lzsteri, for example, 
they being nearer together, merely, on the stolons; and at the 
other extreme colonies in which the zooids ‘are as completely 
enveloped by a common test as they are in Botryllus or 
Goodsiria.” 
I wish here to reaffirm and emphasize this statement in its 
fullness. I have several times reéxamined my material with a 
view to finding some constant structural difference that would 
enable me to separate specifically the one extreme from the 
other; but each effort has resulted in strengthening the convic- 
tion that such a separation is impossible. It may be worth 
while to add that I have reéxamined the case since having had 
opportunity to study several other species of Pevophora, new 
and old, P. Lzstert included. Last summer I had the pleasure 
of submitting my specimens to the experienced judgment of 
Prof. Herdman, and he agrees with me fully that they are all 
one species. I reassert, then, that we have here within the 
limits of the variability of a single spectes a complete transition 
Srom the Simple or Social Ascidians (depending on what author s 
system of classification be adopted) to the Compound Ascidians; 
or in other words, a complete transition within a single species 
between two groups that have been considered as distinct 
families, Bronn, Gegenbaur; or as distinct suborders, Herd- 
man; or even as distinct orders, Haeckel, Claus. For a 
summary of the various systems of classification that have 
been proposed from time to time, see Seeliger (94). Lahille 
(90) has proposed a wholly new classification and nomenclature 
of the groups above genera, in which the simple or compound 
conditions are entirely ignored as differentiating characters for 
