SECONDARY FOSSILS. 
145 
Palceoniscus , shown in the Wall Cases of Recess 18, occur in 
the Marl-slate of Durham. 
THE UPPER GALLERY. 
In order to study the fossils of the Secondary or Mesozoic 
strata, the visitor should pass to the Upper Gallery by the 
western staircase. Before examining the fossils he may notice 
three small Scroll Brackets, springing from the Table Cases of 
the Gallery, which support glass shades covering miniature repre- 
sentations of the three planets — Mercury, Venus, and the Earth, 
with her satellite, the Moon. These are placed at true relative 
distances from the large gilt globe, representing the Sun, which 
is a conspicuous object at the end of the Gallery, over the door 
leading to the Rock Room. A glycerine barometer, by Mr. J. B. 
Jordan, will be found in Recess 1. 
Turning to the fossils the visitor may commence with those of 
the Trias, or New Red Sandstone — a formation which lies at the 
base of the Secondary series, but others in this country only few 
fossils. Some Triassic plants and invertebrata are placed in the 
lower part of Wall Case 4 ; whilst an interesting collection of 
reptilian remains from the Elgin sandstone, believed to be partly 
of Triassic age 5 i s displayed in the Table Case which stands in the 
Recess No. 3. The reptiles include the crocodilian Stagonolepis, 
the little lizard Telerpeton, the peculiar horned reptile described 
by Mr. E. T. Newton, as Elginia , and the dicynodont genera 
named by him Gordonia and Geikia. Most of these are repre- 
sented by casts, but some of the sandstone originals, showing 
hollow moulds of the bones, are also exhibited. 
The Rhcetic beds, which furnish a transition from the Trias to 
the Lias, are represented by a small series of fossils in Wall Case 
3 and in the drawers of Table Case (A), as well as by some of the 
remarkable teeth of Ceratodus in a Case in the Recess numbered 2. 
Occurring in extraordinary abundance, and in an excellent 
state of preservation, the fossils of the Liassic and Oolitic 
formations necessarily demand a large amount of space. The 
group of Liassic rocks, forming the lowest member, is repre- 
sented in Flat Cases 1 to 7 , and in Wall Cases 4 , 5 , and 6. 
The extinct cephalopods, well known as Ammonites, are 
abundantly represented in the Wall Cases, as also in a Table Case 
(A), in Recess No. 2 ; whilst some of the larger forms are exhibited 
at the head of the staircase. The equally well-known Belem - 
nites (Greek belemnon, “ a dart ”) are the hard internal supports 
of cephalopods. akin to the cuttle-fishes and calamaries. In some 
of the allied forms, like Geoteuthis, the ink- sac, with its in- 
durated pigment, is well preserved. Some fine examples of 
Liassic fish and reptilian remains are in the Recesses 1, 2, and 3. 
The type-specimen of Hybodus de laBechei is in No. 1 ; and the 
head of a large P achy cor mus is also noteworthy. The reptilia 
are represented by specimens of the Ichthyosaurus and Plesio- 
saurus. 
