R. Etheridge, jun.—Carboniferous Tubicolar Annelida. 1738 
‘a Gasteropod, and identical with Spirorbis carbonarius, Dawson. This 
is probably one of the earliest instances of a change of opinion 
amongst Continental Palontologists as to the affinities of G. 
ammonis, G6pp. 
Writing in 1866, Mr. Leo Lesquereux, after having examined 
many specimens of the so-called G. ammonis, states that he “ cannot 
consider them but as the small thick shells of an Annelid,” and 
refers it to Spirorbis carbonarius, Dawson. The species, according 
to Lesquereux, is abundant at Colchester, Illinois, associated with 
the remains of Callipteris Sullivantii, Pecopteris, and Stigmaria, etc., 
and, as with us, leaving deep imprints on the plant surfaces.’ 
It is unnecessary to follow the figures of S. carbonarius by 
Murchison through the various editions of his “ Siluria”’; it will be 
sufficient for the purposes of the present history to notice only those 
of the fourth and last edition, published in 1867. The figures here 
given are the same as those used in the “Silurian System,” and 
represent in a similar manner the British varieties of the species. 
The important point connected with these later references of 
Murchison is his recognition of the identity of his Microconchus with 
Spirorbis.” 
Amongst the many occasions on which Mr. E. W. Binney has 
called attention to the present species, not the least important is that 
on which he described the position and extent of the “Spirorbis 
limestone” in the upper part of the Coal-measures of the North-west 
of England, where it forms a continuous and well-marked bed.* 
We now come to an important paper by MM. Van Beneden 
and E. Coemans,! in which, following Von Roehl, they dispute the 
fungoid nature of the Gyromices, and endeavour, on their own part, 
to prove its relation to the Pulmonate Gasteropoda. MM. Van 
Beneden and Coemans assign to Dr. Andri, of Bonn, the honour of 
being the first to doubt the vegetable origin of Gyromices. They 
consider it most nearly resembles Planorbis, or certain Tubicolar 
Annelides, and would be content to regard it as one of the latter, 
were it not difficult to reconcile the occurrence of marine forms of 
this class attached to the remains of terrestrial or fluviatile plants. 
From this, principally, they are led to look upon Gyromices as a 
Pulmonate Terrestrial Mollusc allied to the Helicide, living 
adherent to the stems and leaves of ferns and other coal-plants as the 
living Spirorbis does on marine vegetation and animals. Jgnoring 
the term Gyromices, they propose for this the name Palorbis. 
In 1868 Major von Roehl gave a detailed notice of this species, 
and is one of the few German authors who has referred it to 
Spirorbis.° 
In 1868 Dr. J. W. Dawson added to our knowledge of his 
Spirorbis carbonarius, by describing the microscopic shell structure, 
1 TIlinois Geol. Survey Rept. 1866, ii. p. 462. 
2 Siluria, 1867, 4th edit. p. 302. 
3 Trans. Manchester Geol. Soc 1866, vi. p. 42. 
4 Bull. l’Acad. R. Bruxelles, 1867, 2Qme ser. XXiii. 
5 Foss. Flora Steinkohlenf. Westphalens, lief. 1, p. 4. 
