OP SOUTHEP.N INDIA. 289 



GROTRIANIA, Speyer, 1860, (see p. 278). 

 1. Grotriania jugosa, Forbes, PL X, Pigs. 12-14. 



1846. Lucina jugosa, Forbes, Trans., Geol. Soc, Lond., vii, p. 142, pi. xvii, fig. 7. 



1847. ,, ornatissima, d'Orbigiiy, Voy. d'Astrolabe, Paleont., pi. iv, figs. 27-28 ; — Lucina jugosa, OiXiQiovum. 



Grot, testa orhiculato lentiformi, superficie concentrice crasse costulata et minu- 

 tissime striata, apicihiis deplanatis et valde approximatis ; margine lunulari pauluUmi 

 insinuato ; lunula et area prof andissime excavatis, earumque marginibus acute projici- 

 entibus ; cardine dente antico cardinali in utraque valva sub-obsoleto, duobus positicis 

 majoribus, quorum medio in v. dextra maximo, dente laterali postico hi valva dextra, 

 antico in valva sinistra sub-ohsoletis instruct o ; impressione muscul. antica obliqua 

 obovata, postica paulo minor e, fere circulari; margine interno minutissime denticulate 

 striato. 



Height of shell about equal to its length. 



Thickness of shell : its length ... ... ... ... 0*47 



The orbicular form, slightly but very regularly convex valves, with flattened 

 umbonal regions, the very deeply excavated lunula and area, the concentric lamellar 

 ribs, which are besides covered with very fine striae of growth, and the fine internal 

 crenulation of the margin are the most prominent characters of this interesting 

 species. It is a true Grotriania, that is, an AstaiHe with deeply excavated lunule 

 and area. 



Locality — Near Odium, in a ferruginous earthy limestone. 



Formation, — Ootatoor group. 



GOULD lA, Adams, 1851, (see p. 279). 

 1. GouLDiA PLANissiMA, Forbcs, PI. X, Pig. 3. 



1846. Astarte planissima, Forbes, Trans., Geol. Soc, Lond., vii, p. 143, pi. xv, fig. 23. 



1847. „ ccelata, Miiller, Petref. Aach. Kreidef., p. 22, pi. ii, fig. 3. 



Gould, testa sub-quadrangulari, compressiuscula, margine areali et lunulari ad 

 apicem angulum fere rectum for mantibus, regione umbonali deplanata, postice paulo 

 angustiore quam antice, et rotundate truncata ; superficie costis paucis ^6-9 J crassis 

 concentricis tecta ; cardine in valvula sinistra duobus dentibus cardinalibus, crassi- 

 usculis et uno postico elongato laterali, in val. dextra tribus cardinalibus, medio 

 maximo alteris sub-obsoletis, et uno laterali antico longo instructo. 



Height of shell : its length ... ... ... O'QO 



Thickness of both valves : „ ... ... ... 0'57 



I have compared authentic specimens, received from Dr. Bosquet, of Miiller' s 

 Astarte ccslata, and I can see no perceptible difference between them and our 

 shell. The flattened umbones and the comparatively few but very strong con- 

 centric ribs characterize the species, and distinguish it apparently from Miinster's 



