R. Etheridge, jun.—Carboniferous Tubicolar Annelida. 263 
S. spinuliferus, Nicholson,’ is allied to S. spinosa in the presence 
of strong spiniform projections. 
Loc and Horizon.—Skateraw and Catcraig Quarries, near Dunbar ; 
Burlage Quarry, near Dunbar; in shale of the Lower Carbon- 
iferous Limestone Group ; Gair Quarry, near Carluke, etc., in shale 
of the Upper Carboniferous Limestone Group (Mr. J. Bennie). 
6.—Spirorbis 2? (Serpula) Archimedis, de Koninck ? 
Serpula Archimedis, de Koninck, Descrip. des Anim. Foss. p. t. G, f. 6. 
Bronn, Index Pal. Nomen. 1848, p. (without description). 
+ Bigsby, Thes. Dev.-Carb. 1878, p. 248 (cid). 
Obs. —Mr. Bennie has found a single specimen which appears to 
have relation with the above species. Unfortunately it is only an 
internal cast, but the turriculated form of the coil, and certain indis- 
tinct traces of transverse ridges, such as are described by Prof. de 
Koninck in 8S. Archimedis, render it likely that we may have to 
catalogue this as a British form. 
Loc.—Law Quarry, near Dalry, Ayrshire—Carboniferous Lime- 
stone Series (Mr. J. Bennie). 
7.—Spirorbis Hichwaldi, sp. nov. (Plate VII. Figs. 22-24.) 
Sp. carbonarius, Murchison, var. R. Etheridge, jun., Grou. Mac. 1877, IV. p. 319. 
Sp. char.—Tube planorbiform, dextral, of from two and a half to 
three volutions, usually all more or less in the same plane; the 
volutions convex on one side, the upper, but flattened on the lower, 
as if by attachment. Surface usually quite smooth, but sometimes 
with a few transverse ridges; the periphery of the tube sharp, 
produced into a series of short, minute, regular, spiniform processes. 
Aperture oval ; umbilicus shallow and open. 
Obs.—In a few ‘ Paleontological Notes” communicated to the 
Grotoaicat Macazine I pointed out the occurrence of this peculiar 
and pretty form of Spirorbis in the Lower Carboniferous beds of the 
Edinburgh neighbourhood, which so directly calls to mind the 
Russian Silurian species, S. Siluricus, Hichwald.?, Formerly I con- 
sidered it better to regard S. Hichwaldi only as a variety of the 
common Lower Carboniferous form, but on reconsidering the matter, 
and after the examination of a large number of individuals of the 
latter from different localities, and free from matrix, kindly prepared 
for me by Mr. Bennie, it appears to me necessary to keep S. Hich- 
waldi distinct from S. pusillus, Martin (= S. carbonarius, Murch.). 
Of the many hundred examples of the latter I have examined not 
one has presented the tubercular periphery of S. Hichwaldi, and, per 
contra, all the individuals of the latter which have come under my 
notice have possessed this character. From S. Siluricus, Hichwald, 
our new form differs in a much less degree, but it may be stated 
generally that the shell is much larger in the former, and the spin- 
ous processes are smaller and less developed; the aperture is semi- 
lunar instead of oval, and the umbilicus deep instead of open and 
shallow. 
1 Pal. Ontario, pt. 2, pp. 83 and 84, f. 44c. 
2 Letheea Rossica, i. p. 668, t. 34, f. 1, a-c, 2 a and b. 
” Pd 
