19G CRETACEOUS PELECYPODA 



is a Ccromi/a (sec p. 78). However, of the five siieeies which I have to mention only four arc 

 KiilHciently well preserved to admit of a reliable determination, Feniella ( renilicardia) oblrunccUa , 

 Cyprina Forhe&iana and cristata, and Ci/prina (Clcatrea) conlialis ; one species apparently belong- 

 ing to Trapezium is only known from a single imperfect valve ; until better specimens have been 

 discovered it would be useless to burden our literature with names which cannot have any value 

 either for the geologist or palaeontologist, but would only remain a puzzle to the concholugist. 



Tims, looking at the family Glossidje, as rppvcsented in cretaceous rocks, we 

 find a great number of well defined species belonging to Veniella, one or two may 

 be Glossocardice and a few belong to Cyprina proper, and its sub-genus Cicatrea. 

 Of Glossuis itself not one species is known with certainty, but that form of shell 

 does occur. Few species also externally resemble Trapezium, but none is sufficiently 

 certainly known by its hinge. Apricardia is as yet entirely cretaceous and so is 

 Cicatrea, but both are likely to occur in other formations also, the first most 

 probably in the tertiarics, the last in the upper jurassics. 



TRAPEZIUM, 3Ieo. v. Miihlf., 1811, (vide p. 186). 

 ? Trapezium, sp. ind., PL XIII, Fig. 4. 



A trapezoid, or almost quadrangular left valve, moderately inflated, with a pro- 

 minent sub-obtuse beak ; the region between it and the postero-inferior end is 

 the highest, and from it the shell slopes very gradually on either side, the supero- 

 posterior and antero-inferior extremities being mostly extended ; the surface is 

 covered with minute radiating striae and a few distant concentric grooves, indicating 

 stages of growth. Hinge-teeth unknown. 



The remarkably quadrangular form of this species and the moderate thickness 

 of its shell make it probable that the species belongs to Trapezium, but it was 

 impossible to trace the hinge-teeth in the only figured right valve known. 



Localitij. — North of Serdamungalum, in a yellowish highly calcareous conglo- 

 meratic sandstone. 



Formaiwn. — Trichinopoly group. 



VENIELLA, Siol., 1870, (vide p. 189). 



Veniella [Venilicardia] obtruncata, Sloliczka, PI. VIII, Figs. 1-7. 



Ven. testa sub-qiiadrangidari, valde injlata, crassa ; nmbonibtts iiicurvis, approxi- 

 matis, obtusiuscrdis ; lunula moderate excavata, sub-rotundata, latiuscula, liiiea impircssa 

 margiiiata, area loiiga angusta, siih-profunda, et nymphis crassissimis instructa ; valcis 

 in regione ab umbonibus ad terminationem postero-inferiorem extensa rnaxime eletatis, 

 ab ea elevatione antice versus gradatim et convexlusciile-, postice rapide-deeUci ; 

 siiperjicie striis concentricis tenuihiis ac nonuullis crassioribits notata ; cardo in valoa 

 dextra dente longo postico indistincte bifido, curvato, oblique desoendente ac altera 

 unlico horizontalUer extenso, inatqualiler diviso, postice maxime elevalo, in culca 



