81 
Ohservation. — It is a long time since I expressed the opinion that the 
Spirifer<B, the names of which are mentioned in the synonymy, are in reality 
hut varieties of one and the same species, and I am pleased to see that Messrs. 
Davidson and J. Hall look at it in the same way and make the same remarks. 
In fact, I do not know a single really constant character which sanctions the 
separation of Spirifer ArcMaci, and Lonsdalei, Murchison, and Spirifer 
calcaratus, Sowerhy, from the true S. disjunctus or VermulUi. In bringing 
togetlier a large nnmher of specimens of this species, one passes insensibly 
and by gradual transition from the elongate Spirifer Murchisonianus with 
rounded sides, to the broad Spirifer calcaratus with very extended and very 
acute lateral extremities. 
Horizon and Localities. — This species is very abundant in the Upper 
Devonian Dormation in the Calceola sandalina and Strigocephalus Lurtini 
beds, and may he used to characterise them. 
It is found at a great numl^er of localities in Belgium, Germany, 
England, Ireland, Erance, Bussia, the United States, and even in China. 
In New South Wales internal casts of this species fill, almost exclusively, a 
very hard, siliceous white sandstone at Bowenfels,^ another, yellowish and 
softer, at Sofala, and a third, brownish red, at Colocolo. At Collin’s Elat, 
near Bungonia, this Spirifer occurs in a greyish very compact magnesian 
limestone. 
2. Spirtfeu multiplicatus, L. G. de Koninch. 
PL III, fig. 5. 
Shell broad, greatest width at the hinge line ; valves moderately 
arched ; the mesial fold of the dorsal valve, which is the only one well known, 
is little raised, angular in the middle and separated from the lateral regions 
by a rib, one of the sides of which is more developed than the other ; its 
surface is ornamented with several other ribs that appear to be thinner than 
those on the surface of the lateral parts ; these last, fifteen on each side, are 
peculiar in their regularity and in the depth of the furrows that separate 
them from one another. In examining them with a lens, it will be seen 
that they are traversed by delicate growth strim producing very thin and 
short imbricating lamellm. The cardinal slopes form a very acute angle with 
the lateral slopes. The area, of which I have been able to see a small portion, 
appeared to me to be well developed, which makes me think that the l^eak is 
rather prominent. The exterior ornamentation of the ventral valve is similar 
to that of the dorsal. 
1 [Mt. Lainbie. — W.S.D.] 
