156 DEVONIAN FAUNA. 



Sp. Verneuilii are so great and intermingled that it may be in that transition 

 stage. 



(4) That some of the shapes of Sp. Verneuilii might from external ornament 

 be placed under the genus Cyrtia. What is known of the internal arrangements 

 of these shells does not separate them from Spirifera, and the size and flatness of 

 their area are certainly not a sufficient reason for doing so. What, therefore, the 

 genus Cyrtia may be worth must depend on structures not seen in our English 

 specimens. These shells also resemble some species of Syringothyris — e. g. 

 S. cuspiclata — externally, but distinctly differ from them internally. 



3. Spirifera obliterata, Phillips. Plate XIX, figs. 1 — 4 a. 



P1810. Spirifer Bouchardi, Murchison. Bull. Soc. Geol. Ft., vol. xi, p. 253, 



pi. ii, figs. 5« — c. 

 1841. Spirifera obliterata, Phillips. Pal. Foss., p. 78, pi. xxxi, fig. 135. 

 1896. — — Whidborne. Proe. G-eol. Assoc, vol. xiv, p. 376. 



Description. — Shell very transverse, fusiform, alate. Hinge-line very long, 

 marked in the cast with crenulations. Cardinal angles very acute. Beak small, 

 incurved. Ventral valve with a narrow sinus, bisected by an elevated line, and 

 dorsal valve with a low narrow fold bisected by a median groove. Dental plates 

 short. Lateral ribs low, rounded, five or more in number (sometimes numerous), 

 gradually decreasing in size, and becoming faint or evanescent on the wings. 

 Ovarian area strongly pitted. 



Size. — Height of dorsal valve 9 mm. ; width 26 mm. 



Localities. — In the Museum of Practical Geology is Phillips's type specimen of 

 Sp. obliterata from Brushford ; in the Barnstaple Athenaeum is a specimen from 

 Top Orchard ; in Mr. Handing's Collection one from Top Orchard ; in my 

 Collection four from Ashhill Quarry near Brushford, and two from near the Kiln, 

 Croyde Bay. 



Remarks. — Phillips's specimen, being on a slab with other fossils, was un- 

 observed at the time that Davidson described the Devonian Brachiopoda. It has 

 since been recognised, and proves to belong to a definite species of which several 

 other examples have occurred in the Pilton Beds. This specimen is in poor con- 

 dition, and may perhaps have been slightly shortened by pressure. The usual 

 shape of the species appears to be still more transverse. It seems to be 

 distinguished by its small, narrow, undefined fold and sinus, and by its low 

 rounded ribs, which seem to vary considerably in number, to be broad and 

 prominent near the centre, and to diminish rapidly and regularly toward the sides, 

 so that the wings sometimes appear almost smooth. The fold is very undefined ; 



