318 R. Etheridge, Jun. — Palceontologieal Notes. 
VIII. — PALiEONTOLOGICAL NOTES. 
By R. Etheridge, Junior, F.G.S., etc. 
T HE following brief notes on rare, little known, or occasionally 
new fossils, in some cases anticipating more detailed descriptions, 
may be of interest to the readers of the Geological Magazine. 
1. Spirorbis ambiguüs, Fleming (Edinb. New Phil. Journ., 1825, 
vol. xii. p. 246, t. 9, f. 3). — This little Annelide appears to have been 
a good deal lost sight of by palaeontologists, and for that reason it 
may perhaps be well to call attention to it. S. ambiguus was not 
mentioned by Prof. Morris in his “ Catalogue of British Fossils,” 
nor by Messrs. Armstrong and Young in their “ Catalogue of the 
Carboniferous Fossils of the West of Scotland.” It was originally 
described by the Rev. Dr. Fleming, in his paper on the British 
Testaceous Annelides, and placed in the second division of his 
arrangement of the species of the genus Spirorbis, those with the 
tube “ destitute of longitudinal ridges.” He obtained it from Cult’s 
Limeworks, near Pitlessie, Fife, adhering to the surface of Myalina 
crassa, Flem. The tube expands towards the aperture, which is round ; 
the umbilicus is open, and the surface unornamented, or very finely 
wrinkled across. Unlike Sp. carbonarius, Murchison, it does not, so far 
as I have observed, make a groove for itself in the surface of the body 
to which it is attached. In general appearance Sp. ambiguus closely 
reseinbles Spiroglyphns marginatus, M'Coy. It will be a question for 
careful consideration whether this species, from its early enunciation, 
will not absorb some of the later described forms ; amongst the latter 
I would recommend particular attention being paid to S. minuta, Port- 
lock, and S. omplalodes, Goldfuss. Mr. Bennie has obtained S. am- 
biguus from Roscobie Quarrv, Fife, in addition to the typical locality. 
[Shale above the Roscobie Limestone, L. Carb. Limestone group.] 
2. Spirorbis carbonarius, Murchison, var. ? — The abundance 
with which the typical form of S. carbonarius is to be met with in 
all the strata about the horizon of the Burdiehouse Limestone 
(Cement-stone group of the L. Carboniferous or Calciferous Sand- 
stone Series) is something wonderful. In a quarry on the Linnhouse 
Water, opposite the Oakbank Oil Works, near Mid Calder, there is a 
small band of limestone almost entirely made up of this species, 
and in Company with it is to be occasionallv found another peculiar 
and liandsome little Annelide, which has not before corne under my 
notice. It has the general characters of S. carbonarius , but the 
periphery is produced into a number of minute tubercules, almost 
amounting to spines, which give to the tube a very distinctive ap- 
pearance. There is a described species having this character, 
Spirorbis Siluricus, Eichwald (Lethsea Rossica, vol. i. p. 668, t. 34, 
f. 1), from the Coral Limestone of the Isle of Oesel, and the Old Red 
Sandstone of the Department of Novgorod, and so like are our 
Lower Carboniferous forms to it, that I do not know how to distinguish 
them, although I scarcely like listing it under Eichwald’s name 
without a direct comparison of specimens. In the mean time, as its 
other characters correspond with those of S. carbonarius, we may 
consider it as a well-marked variety of that species. 
Collector, Mr. James Bennie. 
