306 RR. Etheridge, jun.— Carboniferous Tubicolar Annelida. 
2. CARBONIFEROUS. 
a. With borders. 
Serpulites carbonarius, M‘Coy. 
a membranaceus, M‘Coy. 
11.—Serpulites carbonarius, M‘Coy. (Plate VII. Fig. 29 and 29a, 6.) 
Serpulites carbonarius, artes Synop. Carb. Lime. Foss. Ireland, 1844, p. 170, t. 23. 
* +) M‘ oy. Brit. Pal. Foss. 1851, fas. i. p. 181. 
* Morris, Cat. Brit. Foss. 1854, 2nd ed. p. 93. 
? Campylites carbonarius, Eichwald, Bull. Soe. Nat. de Moscou, 1856, No. 2, p. 408. 
? Ki Eichwald, Lethaea Rossica, 1860, 1. p. 676. 
Serpulites Be Young and Armstrong, Cat. W. Scott. Foss. 187, p. 42. 
3 Ss Etheridge, jun., Quart, Journ. Geol. Soc. 1878, xxxiv. p. 9, 
: Upp dls StS 
5 3 Bigsby, Thes. Dey.-Carb. 1878, p. 2438. 
Sp. char.—Tubes varying in size, elongated, thin, shelly, and from 
one and a half to three lines in width; mano like, but not undulated, 
intertwined, or contorted; lateral thickened ridges, strong and 
persistent. Surface shining and smooth, or with very fine, broken, 
longitudinal striz. 
Obs. —Although by far the most abundant Serpulites in the 
Carboniferous beds of Scotland, and by no means rare in England, 
is seldom found with the posterior terminal tubes preserved. It is 
invariably met with in the form of a compressed, or flattened, elon- 
gated, narrow tube, usually more or less shining, and very frequently 
possessing a delicate bluish or bluish-white bloom arising from the 
formation of an amorphous form of Vivianite, or Phosphate of Iron. 
I believe these Serpulites tubes, like the genera Lingula, Conularia, 
and a few others, to have possessed a fair quantity of horny, or 
chitinous matter in their composition. 
The lateral thickened ridges are usually well shown, and appear 
to terminate in the posterior bifurcation. The length is considerable, 
reaching, according to M‘Coy, upwards of five inches, although I 
have not measured one quite so long as this. In certain examples 
collected from the Wardie Shales of the neighbourhood of Edinburgh 
I found the surface to be delicately longitudinally striate ; instead 
of simply smooth and plain, as is usually the case. 
From Serpula (Serpulites) compressa, Sow., the present species is 
distinguished by its narrow, elongate form, two lateral thickened 
ridges, and the absence of the elliptical secre of the former. From 
the next species to be described, S. membranaceus, it is less easily dis- 
tinguished, the points relied upon for separation being more those of 
degree than actual difference, S. membranaceus being, so to speak, 
much larger, more delicate in structure, less shelly, and, so far as 
I know, citnann the two elongated posterior tubes, although it 
possesses, according to M‘Coy, similar thickened margins. 
Loc. and Horizon. —W8. carbonarius occurs in a bed of marine shale 
in the Wardie shale beds of the L. Carboniferous (Calciferous Sand- 
stone Series), at Woodhall, Water of Leith, near Edinburgh. It is. 
met with in the Carboniferous Limestone Series, both of the east and 
west of Scotland, in some abundance and at various horizons, being 
particularly plentiful in shale at Whitfield Quarries, near Carlops, 
