228 SUPPLEMENT TO THE BRITISH 



Obs. — In 1852 I provisionally described a French example of this fossil as a mal- 

 formation of Sp. rostratus, but subsequently M. E. Deslongchamps, having discovered 

 that the shell occurred in the Middle Lias of Fontaine-Etoupe-Four in Normandy, and 

 always with the same shape and characters, described it under the name of adscendens. 



During a visit to the Bridport Institution Mr. C. Moore noticed the fine example 

 figured in our plate, which is stated to have come from the Middle Lias near Chideock. 

 As it is the only British example with which I am acquainted, a search for others in 

 the same locality would be desirable. A fine specimen of Tliecidium Moorei is attached 

 to one of its valves. 



243. Spiriferina Tessoni, var.?, Dav. Sup., PI. XXIX, fig. 21. 



Spikiferina Tessoni, Dav. Annals and Mag. Nat. Hist., vol. ix, 2nd ser., pi. xv, 



figs. 1, 2, 1852. 



Shell transversely semicircular, wider than long ; hinge-line straight, not quite as 

 long as the greatest breadth of shell ; cardinal angles rounded. Dorsal valve convex, 

 and divided into three portions, the central one forming a moderately elevated and 

 sharply defined, rounded mesial fold. Ventral valve much deeper than the opposite 

 one ; area large, nearly flat, and triangular, and sloping back at an almost right or 

 obtuse angle with the plane of the dorsal valve, and divided by a triangular fissure ; the 

 beak much produced, and bent upwards near its extremity. Surface of both valves 

 ornamented by a variable number of small angular plaits or ribs, from thirty to thirty- 

 five in number, of which more than half are due to bifurcation or intercalation at variable 

 distances from the beak and umbone. From the ribs, at intervals, rise short vertical 

 spines, in addition to the minute perforations which traverse the shell. 

 Length 11, width 14, depth 11 lines. 



Obs. — Some French examples of this fine species have attained, and even exceeded, 

 22-| lines in length, by 35 in width, and 16 in depth. The species was first found in the 

 Middle Lias of Fontaine-Etoupe-Four in Normandy by Messrs. Tesson and E. 

 Deslongchamps. 



During a recent visit to the Museum of the Bridport Institution Mr. C. Moore 

 observed a specimen of this species stated to have been obtained from the Middle Lias of 

 Chideock, and kindly borrowed the specimen that I might figure and add it to my 

 Monograph of British Oolitic and Liassic Brachiopoda. 



