360 HIND : CARBONIFEROUS AMlVtONOIDS NEW TO ENGLISH ROCKS. 
Locality.— rCarboniferous Limestone ; Kniveton. (Derbyshire), 
Clitheroe (Lanes.), Rathkeale and St. Doulaghs (Ireland). 
Observations. — In full-grown examples, as de Koninck points 
out, this species resembles very closely G. truncatum Phill., but the 
latter has a much wider umbilicus. The sides of the periphery of 
G. inconstans are much more sub-quadrate, and the broad trifid median 
lobe of the suture is altogether different from that of G. truncatum, De 
Koninck also lays stress on the presence in young examples of 
G. inconstans of 3 or 4 radiating grooves which he evidently thinks 
do not occur in G. truncatum. These folds are not well understood, 
and as far as I am aware are not of specific value, but they certainly 
are present in some of the British specimens from Kniveton. A 
single large specimen labelled " Clitheroe " from the collection of the 
late James Spencer, of Halifax, now in my possession, I consider 
belongs to this species. 
I would call attention to the suture line of G. crassum as figured 
by Foord, {Carb. Ceph. Ireland, PI. XLII, fig. 10c) ; which is very 
similar indeed to that of G. inconstans. His species is from a Lower 
Limestone locality. In England G. truncatum is quite common in 
the G. crenistria zone, but Foord has recorded this species from 
Lower Limestone localities in Ireland. The actual horizon from 
which Phillips obtained his type specimen is obscure, as he only mentions 
BoUand, w^hich is the name of a district where all horizons of the 
Lower Carboniferous beds occur. I have, however, collected specimens 
of G. truncatum only from the higher beds of the series at Black Hall 
and Cold Coates, near Chipping, and from Dg beds at Castleton and 
Chrome Hill and Elbolton ; and in Belgium from the upper beds of 
Vise. At Kniveton G. inconstans occurs with Pericyclus fasCiculatus', 
and it is important to note that both species occur at Pauquys in 
Belgium — a much lower horizon than the Visean. 
CxLYPHIOCERAS OBESUM Foord. 
Glyphioceras {Muensteroceras) ohesum Foord 1903 ; Carb. Ceph. 
Ireland, p. 196, PI. XLIII, figs. 3 a-c. 
Specific Characters. — Shell, large sub-globose, somewhat com- 
pressed, involute, more so in old age. Greatest thickness at umbilical 
margin. Height of outer whorl about one-third the diameter, broadly 
