J. G. H. Godfrey—Association of Stibnite and Cinnabar. 369 
as far up as the contracted margin of the mouth. In another 
specimen of the recent species, there is an absence of constrictions, 
but a more lengthened and contracted mouth than in the former figure ; 
whilst in a third example the constrictions are visible much lower 
down than in either of the other examples, and the mouth is com- 
paratively little contracted. 
Turning, now, to the minute fossils, which I believe to be referable 
to Ditrupa, we in the first place observe one, Pl. VIL, in which the 
constrictions are very numerous and well-marked; another, in which 
they are continued regularly between the two apertures; and lastly, 
a third example, in which the constrictions are almost absent. 
Dr. Bigsby! gives Ditrupa Carbonifera, De Ryckholdt, as occurring 
at Craigenglen in Stirlingshire, but I am not acquainted with the 
published reference to this. 
Ditrupa Ryckholdti may be distinguished from both the species 
described by De Ryckholdt by its much smaller size, the regularity 
of its ornamentation, and the very slight curvature of the tube. 
Loc. and Horizon.—Woodend Quarry, near Fordel, in shale above 
the No. 2 Limestone of the L. Carboniferous Limestone Series (J/r. 
J. Bennie). 
VIII.—On rue AssocraTion oF STIBNITE AND CINNABAR IN 
Minerat Deposits. 
By J. G. H. Goprrey, F.G.S. 
HE association of stibnite and cinnabar appears to have been 
first noticed at El Haminat,? in the province of Constantine 
Algiers, where, during the years 1850 to 1852, considerable quan- 
tities of both these minerals have been raised from veins traversing 
Cretaceous schists. Other localities in Algiers showing the same 
association are: Ghelma near Phillipsville, where cinnabar in 
crystalline crusts covers and penetrates antimony ochre derived from 
the decomposition of stibnite, the containing rock being a saccha- 
roidal limestone; Debar, 19 kilometers to the N.W. of Ghelma, > 
where stibnite is found covered with spots of cinnabar, the gangue 
being heavy spar; Traia, showing a similar occurrence to the pre- 
ceding; Tasselemet, where radiating crystals of stibnite occur 
imbedded in earthy cinnabar. 
In Mexico, at Hentzuco, cinnabar has been observed as a 
coating upon stibiconite, showing pseudomorphs after stibnite. 
Recently Dana* described a new mineral, Livingstonite, which had 
been discovered at the mine Ayoque de Huitzero, Mexico, in a 
matrix of carbonate and sulphate of lime, together with sulphur, 
cinnabar, stibnite, and valentinite. This mineral, of a hardness 2, 
spec. gr. 4:81, occurs in prisms and columnar groups like stibnite. 
1 Thes. Dev.-Carb. p. 243. 
2 Guide pratique de minéralogie appliqué, par A. F. Nogués, Paris, 54, rue des 
Saints fréres, vol. ii. pp. 131. Notice sur les gites mineraux et les materiaux de 
construction de |’ Algerie, par M. Ville, ingenieur en chef des Mines, Ann. des Mines, 
6th série, tom. xvi. 1869, p. 161. 
3 Dana, System of Mineralogy, 5th edition, vol. ii. appendix, p. 36. 
DECADE II.—VOL. VII.—NO. VIII. 24 
