48 BRITISH DEVONIAN BRACHIOPODA. 



? Spiriferina insculpta, PhiMijps (sp.), var. PI. VI, figs. 16, 17. 



Spirifera inscdlpta, Phillips. Geol. of Yorkshire, vol. ii, p. 216, pi. ix, figs. 2 and 3, 1836. 

 Spiriferina — Dav. British Carb. Brachiopoda, p. 42, pi. vii, figs. 48 — 55, and 



pi. lii, figs. 14, 15. 



Spec. Char. Shell somewhat pentagonal, wider than long ; hinge-line straight, and 

 usually slightly shorter than the width of the shell ; cardinal angles rounded ; area 

 triangular and slightly curved. Dorsal valve moderately convex, with from five to seven 

 strong angular ribs, of which the central one is the largest. Ventral valve slightly deeper 

 than the opposite one, with from four to six strong angular ribs, divided by a sinus of 

 greater depth ; beak incurved ; fissure partly arched over by a pseudo-deltidium. Surface 

 of the shell closely and regularly intersected by numerous concentric laminae of growth. 

 Shell-structure perforated . 



Length 7, width 8, depth 5 lines. 



Obs. It is possible that the shell under description may be nothing more than a 

 modification of Sp. crista fa, with fewer and stronger ribs. It bears also some resemblance 

 to certain examples of Spiriferina crispa, but more so to the Carboniferous Sp. itisculpta, 

 with which it is, at any rate, provisionally identified. 



It occurs in the Middle Devonian limestone of Lummaton, near Torquay. 



Spiriferina laminosa, M'Coy, has been stated by Mr. Salter to occur in the Marwood 

 beds of North Devon ; but I have not been fortunate enough to procure examples. 



Genus — Cyrtina, Dav. 

 Cyrtina heteroclita, Defrance, (sp.) 1 PI. 9, figs. ] — 10. 



Calceola heteroclita, Defr. Die. Sc. Nat., vol. lxxx, fig. 3, et De Blainville, Malaco- 



logie, pi. lvi, fig. 3. 

 Spirifer hetehoclytus, Buck. Ueber Delthyris oder Spirifer und Orthis, p. 40, 1837 . 



and M6m. Soc. Geol. de France, vol. iv, p. 186, pi. viii, fig. 11, 



1840. 



— heteroclita, Phillips. Pal. Foss. of Cornwall, Devon, and West Somerset, p. 72, 



pi. xxix, fig. 125, 1841. 



— subconica, var. Sowerby (not of Martin). Trans. Geol. Soc, 2ser.,vol. v, pl.lvii, 



fig. 10. 

 Spirifera (Cyrtia) heteroclita, M'Coy. British Pal. Foss., p. 377, 1852. 



1 Some palaeontologists have spelt the term Heteroclitns with a y (Heteroclytus), but the first is the 

 correct spelling. Heteroclitus means originally a verb irregularly declined ; in Gree'c, erepoKXhos, with 

 the < short. 



