420 CRETACEOUS PELECYPODA 



10. Rabula [Limatula] persimilis, Stoliczka, PI. XXIX, Figs. 4-5. 



B. \Lim.'] testa elongata, paulo obliqua, injlata, antice et postice leviter convexa, 

 infra sub-rotundata, medio costulis tenuibus 15-20, radiant Ibtis, striis incrementi 

 minntissiviis, confertissimis et nonnnllissulcis profimdioribus iiitersectia, tecta ; umbo- 

 nibus tumidis, anynstis, modice pirojicientibus ; aiiricnlis liurvis, ad maryinem superum 

 2)aulidum incrassatis, declims, in utroque latere submargine leviter insinuatis ; area 

 cardinali obliqua, medio fovea triangulari ligamentifera, lata, instructa. 



Shell elongated and rather inflated, slightly oblique, with somewhat com- 

 pressed, tumid, and moderately projecting umbones ; the margin of the ears is 

 slightly thickened; the median convexity of each valve is marked with 15-20 radiat- 

 ing ribs, sharp, but not much prominent, slightly rugose by the numerous and fine 

 striae of growth, and intersected by a few more distant narrow grooves indicating 

 stages of growth. Young shells have sometimes only 15 radiating ribs ; they are 

 always more inflated and narrower when compared with full grown specimens, in 

 which the number of ribs rises to 20. 



This species is very closely allied to some of the forms which are usually 

 referred to B. semisulcata of Nilsson. There are, however, at least two different 

 species mixed up under this name. Sowerby's semisulcata from Blackdown is 

 distinct from that of Nilsson, and it is not certain whether the form delineated 

 by Goldfuss under that same name does also not refer to a distinct species, while 

 that figured by d'Orbigny comes very close to Nilsson's type. The Indian 

 form differs from all these by the more distant and almost smooth radiating 

 ribs; but their number agrees especially with Goldfuss' semisulcata: the only 

 difference between the two is, that the European form is a little shorter than the 

 Indian. D'Orbigny's semisulcata has the ribs very distinctly spinulose and is 

 less inflated than j)ersimiUs. 



Localities. — Near Poothoor and Kullay, in a yellowish broAvn limestone, and 

 north of Odium, in a brown sandy limestone. 



Formation. — Ootatoor group. 



11. Radtjla [CtenoidesJ tecta, Goldfuss, PI. XXX, Fig. 12. 



1836. Lima tecta, Goldfuss, Petr. Germ, ii, p. 91, pi. 104, fig. 7. 



1837. ?Lima frondosa, Duj., M^m. Soc. Gfol., l""' ser., pt. ii, p. 227, pi. 16, fig. 10. 

 1839. Lima lamellosa, Roemer apud Geiuitz, Char., pt. i, p. 23. 



1841. Lima tecta, apud Koemer, Verst. Nordd. Kreid., p. 58. 



1843. ?Lima „ d'Orbigny, Pal. fran?. terr. cret., iii, p. 547, p. 419, figs. 5-8. 



1867. Lima „ Gudranger, Album paleont. de la Sarthe, pi, xxiv, fig. 11. 



R. [Cfeno.] testa elongate sub-ovata, paulo obliqua, convexe compressiuscula, 

 antice oblique sub-truncata, auriculis magnis incequalibus et umbonibus depressius- 

 culis instructa, costulis confcrtis radiantibus, scepe irrcgulariler dichotomic, afque 

 lamellis lG-20 concentricis, exstantibus et in auriculas continuis tecta. 



I can see no difference between Indian specimens of this characteristic 

 species and those from Europe. Wiieu the ears are broken away, the shape of the 



