TMETOCERAS HOLLANDiE. 
275 
yielded single examples, namely, in Dorset, Broad Windsor, Bradford Abbas, and 
a quarry on the Marston road about two miles from Sherborne ; in Somerset, 
Horethorne Down near Gorton : and in Gloucestershire, Penn Wood near Stroud. 
The specimen from Broad Windsor came from what might be properly regarded 
as the base of the Murchisonge-zone ; the specimen from Bradford Abbas indicates 
the Paving-bed {Murcliisonse-zone), and it is very quickly coiled ; the Marston-road 
example is a mere fragment of a coarse-ribbed form, it probably came from the 
the bed where the MurcMsonse- and OjMlinum-zones coalesce ; the Horethorne 
Down fossil is probably from the Murchison x-zone ; while the Gloucestershire 
specimen is from the " Sandy Ferruginous Oolite " which overlies the bed in 
which Lioc. opalinum is abundant, and from such little evidence as is obtainable 
this sandy Oolite may be regarded as the uppermost bed of the Opalinum-zone. 
An evolute example with gibbous sides and distant ribs is depicted in 
PL XLYIII, figs. 1 — 3 ; a rather quicker-coiled, flatter-sided, closer-ribbed form 
is shown in figs. 4 — 6, and its suture-line in fig. 7 ; while a more involute variety, 
with closer-set ribs indicating how the next species might be evolved, is drawn in 
figs. 8 — 10. Of these forms the first is the most typical — that is, the most like 
Benecke's original; while the last is really intermediate between scissiis" and 
" Hollands," and almost merits a varietal name. 
Tmbtocbeas HollandtE, 8. Biichnan. Plate XLVIII, figs. 11, 12. 
1883. CosMOCEEAS Hollands, S. BucTcman. New species of Ammonites ; Proc. 
Dorset Field Club, vol. iv, pi. ii, 
fig. 2 (not pi. i, fig. 2, see Tmetoc. 
scissvm). 
This is very likely a dwarf form. It is the further development of Tmetoc, 
scissum, var., shown in PI. XLVIII, figs. 8 — 10, which specimen may be regarded 
as the link exactly intermediate between this form and the typical Tmetoc. 
scissum. The present form, however, difiers not only by its considerable 
inclusion (nearly one-half), its closely approximate ribs, and the breadth of its 
compressed whorls, but because the ribs have a distinct backward reclination, 
commencing from the inner third of the whorl. The ventral area is fairly deeply 
sulcate, but the ribs are set at right-angles to the furrow. 
In 1883 I figured the specimen which is the subject of this article as 
*' Gosmoceras Hollandse, var.," considering as the typical form the specimen depicted 
in figs. 4 — 7 of PI. XLYIII. As the latter is evidently referable to Benecke's 
