vixe: carboniferous and permian polyzoa. <S^^, 
to have a true goneciiim, rather than gonocyst, formed in the angle 
of a dichotomised branch of Ciji^todictya paralleki. I have two or 
three other examples of this form of Gonoecium, but the specimens 
are very rare, iind wliat I have got are pickings from hundreds of 
fragments. 
In figures ^4 and 25 two characteristic examples of "growths" 
on the Zoaria of Cf/sfodicft/a pdvalkla are given. In figure 25 the 
growth arises from the middle of the Zoarium and is drawn slightly 
sideways, and not artisticall}' on the flat, for the purpose of showing 
its relation to the Zoarium. I have other examples of a similar 
growth to this one, and one fragment of Cjjatodictya from which the 
excrescence" has been broken, and a shallow pit is all that is left on 
the Zoarium to indicate its former place. In a section, however, of a 
similar broken base (fig. 27) small vesicular openings mark the 
character of the bases of the excrescence. In fig. 24 the excrescence 
is marginal and of the character shown. I am not certain, however, 
that I should be justified in calling these Gonocysts, but in a certain 
sense they are reproductive, for from some, if not from all these 
excrescences, newer l^ranches originate. Various excrescences are 
found in the Wenlock Shales, adherent to Polyzoa and corals alike, 
and Mr. Ulrich has found and described species somewhat similar to 
our own, in the Lower Silurian Rocks of America. These American 
forms are distingushed by the generic term Gratenporay Ul.," and 
Mr. Ulrich describes several species, and remarks as follows : — " This 
genus includes several species, which occur in circular or expanded 
forms, presenting a minutely striated or pitted surface. Although I 
have examined a large number of good specimens, many of which 
were cut for examination with the microscope, we are not altogether 
certain that the genus should be referred to the sponges. It possesses 
characters entirely peculiar, and probably is a true Palaeozoic type." 
That this may be the ultimate destination of some of the " excres- 
cences" I have but little doubt, while others I can only regard as 
basal colonial growth of similar or dissimilar species. 
A reference to plate iv., figs. 14 to 17, will be sufficient to prove 
that though the Zoarium of Goniocladia is different from that of 
* Jour. Cine. Soc. Nat. Hist., vol. ii., p. 29, pi. vii. 
