114 GANOID FISHES OF THE CARBONIFEROUS FORMATION. 
should say that the principal rays must have been unarticulated for some extent of their 
length. 
The ventral is also not in very good condition; as the specimen lies, it is placed 
nearer the anal than the pectoral. It appears small, but the broken up condition of its 
rays indicates that its size and form are not accurately preserved. 
The dorsal commences slightly in front of a point midway between the posterior 
border of the gill cover and the commencement of the caudal fin. Its shape is triangular 
acuminate, its height in front attains 13 inches—though it must have been higher, as the 
base of the fin is partly concealed owing to the oblique compression of the specimen. 
The rays of the dorsal are rather distantly articulated, and each joint is ornamented on 
its exposed surface by one prominent smooth ridge or longitudinal elevation. ‘l'races of 
oblique slender fulcra are seen along the anterior margin. 
The anal fin agrees closely with the dorsal in configuration and structure ; the length 
of its longest rays is 1? inches. 
The caudal fin is large, inequilobate, and deeply bifurcate; the length of the upper 
lobe, measured from a point in the middle of the tail pedicle opposite the commencement 
of the lower one, being 3? inches. ‘lhe longest rays of the lower lobe attain a length of 
22 inches as preserved, but as the distal extremity of this part of the fin is not shown, 
the original length of these rays may be estimated at 23 inches. These rays of the 
lower lobe are more closely articulated than those of the other median fins, yet though 
the joints become shorter towards the extremities of the rays they never are so short as 
to appear square. ‘The joints also show occasional longitudinal furrows on their ganoid 
surfaces, and the anterior margin of the fin is bordered by minute and oblique slender 
fulcra. The upper lobe possesses a very strong body-prolongation ; its fringe-like rays 
are fine and begin to dichotomise about the middle of their length; the joints are rather 
longer than broad and apparently smooth externally. 
Another specimen belonging to the Royal Scottish Museum has attained a size twice 
as great as that of the above-described original example, as it measures 25% inches in 
length. It is really nearly entire, the extremities of the caudal lobes only being 
deficient. As the general form of body and fins is well shown, it may be of interest to 
give the measurements of the specimen. 
Kutire length from the tip of the snout to the broken off 
extremities of the caudal lobes. : : : . 2 feet 14 inches. 
Hstimated length when entire ; ; ; ; oP eeu) 
Length of head. : : : Ay, 
Greatest depth of body between shoulder and ventral fin . oe 5 
From tip of snout to opposite commencement of ventral fin . Lr 5. 
“; 7. ss Ee dorsal 5 ope Ns 
os 3 eB f anal . ; 16} =Ca, 
5 3 a * lower lobe of 
caudal, 202 =~, 
