506 G. R. Vine—Carboniferous Polyzoa. 
the relative value of the genera and species introduced by various 
authors since the publication of the volumes alluded to. 
Synocladia, King, 1849. 
1873. Synocladia biserialis, Swal., var. carbonaria, Etheridge. 
1878. Synocladia ? scotica, Young and Young.’ 
The type of this genus is very peculiar, and as it is well illustrated 
in King’s Permian Fossils, once seen it can hardly ever be forgotten. 
“The corallum is cup-shaped, with a small central root-like base: 
reticulated, composed of rounded narrow, often branched interstices, 
bearing on the inner face from three to five alternating longitudinal 
rows of prominent edged pores, separated by narrow keels, studded 
with small irregular vesicles alternating with the cell pores.” The 
essential characters of this genus I have put in italics. 
In the ‘Ann. and Mag. of Nat. Hist.,”* Mr. Robert Etheridge, jun., 
described a “‘ peculiar polyzoon from the Lower Limestone Series of 
Gilmerton, under the name of Synocladia carbonaria.” An almost 
identical form had been previously referred, by Mr. Meek,’ to Syno- 
cladia biserialis, Swallow. After very minute investigations, kindly 
supplied to him by Mr. King, Mr. Etheridge says, “I have ascer- 
tained that our Scotch fossil agrees so closely in its main characters ” 
with the American species, ‘‘that it can be only regarded as a 
variety of it.”° 
To Synocladia biserialis Mr. Meek also refers Septopora cestriensis, 
Prout, ‘‘a form which appears to differ only from the typical species 
of Synocladia by having from one to four rows of cell-apertures on 
the dissepiment instead of two.’ ® 
In 1878, Prof. Young and Mr. John Young published’ details of 
another Synocladia, which they called Synocladia (2) scotica, from 
the Upper Limestone Shales, Gillfoot and Garple Burn, stating that 
“in both localities it is very rare.” If we accept the departure from 
the original type of Synocladia, which I have no objection to, seeing 
that Prof. King uses the term for Paleeozoic Polyzoa alone, then 
these two species of the genus may be recorded as existing in 
Carboniferous times. They have the “small irregular vesicles 
alternating with the pores,” not unique with this genus, for several 
others contain a “secondary pore.” Having examined this second- 
ary pore in thin sections of Carboniferous species, I can only account 
for its presence as being indicative of the existence of a vibracula in 
these ancient types. There are, however, most essentially definite 
characters in the Carboniferous Synocladia yet to be accounted for. 
Very frequently, in even the smallest fragments, pores, similar to 
the secondary pores on the face, are constantly found on the reverse 
also. _I know of no analogy in more recent fossil or living species 
to which I can refer to account for this feature in this ancient type. 
ae ees Nat. Hist. Soc. of Glasgow, April, 1878. (The (?) is Messrs. 
: Palecontolog f KE. Nebrask eet * Beptember tore. 
a ogy of K. Nebraska, Washington, 1872. 
Transactions of St. Louis Acad., 1858, vol. i. 
® Sheet 23, Scotch Geol. Survey 6 Thi : 
miricohtike sate 1: y. Jbid. Explanation of Sheet 23, 
