484 CEETACEOUS PELECYPODA 



Association Rules." I need not repeat that this name has no claim to be adopted, 

 for reasons already explained. 



On page 158, note — 



18. Thetlronia. Regarding some additional characters of this genus, as 

 observed in an Indian species, subsequently discovered, see further on (p. 485). 



19. Acora, Conrad, 1870, (Am. Journ. Conch., VI, p. 72). Shell roundly 

 ovate ; right valve with three diverging cardinal teeth, posterior one bifid ; cardinal 

 plate broad, deeply channelled anteriorly, with a compressed, lateral tooth in the 

 middle of the channel ; plate deeply channelled posteriorly. Left valve with three 

 diverging cardinal teeth, the anterior one V (?A-) -shaped, oblique; one distant 

 anterior lateral tooth with a channel above, parallel with the cardinal margin ; 

 nymphaj crenulated on the upper margin, a distant, narrow, channel on the posterior 

 hinge-plate ; pallial sinus deep, reaching to a point in a line with the posterior 

 extremity of the posterior cardinal tooth ; rounded and somewhat ascending ; type, 

 Ae. cretacea, Con., loc. cit., pi. 3, fig. 8. 



Conrad says that this genus is nearly related to Isodoma, but I rather think 

 it should be placed between Ci/cUna and Thetlronia. The type species in general 

 external characters of the shell also closely resembles some Cypmne^'ke. 



20. Scaldia. Two species, >S'. Lamliotheana and Kickxiana, are described 

 under this apparently new generic name by Eyckholt from carboniferous beds of 

 Belgium. The shells are equivalve, roundly ovate, moderately tumid, with con- 

 centric striae of growth : muscular sears two, anterior larger than the posterior ; 

 pallial line with an angular, somewhat ascending sinus, as in Dosinla ; hinge of 

 left valve with a single, tubercular, cardinal tooth below the umbo. (Vide 

 Ryckholt's Mel. paleont., 1852, p. 17, pi. x, figs. 24-28, in M(^m. Cour. Acad., 

 Belg., vol. xxiv). 



On 'page 165 add — 



109rt. Veims Ntjstii, Briart et Cornet (Foss. de Bracquegnies, p. 76, pi. viii, 

 figs. 11-13, in Mem. Cour. Acad., Belg., vol. xxsiv,) is evidently an Eriphyla, 

 and very closely allied to E. lenticularis, Goldf. The latter species is a little more 

 inflated, but specimens with more convex valves (vide pi. vi, fig. 13,) are also 

 often met with, and these hardly difi'er from the Bracquegnies form. 



1096. Venus Lucina, Briart et Cornet, (Ibidem p. 77, pi. viii, figs. 22-23,) 

 is to all appearance a Ci/primeria. 



109c. A species allied to Venus (? Baroda) Boy ana, d' Orb., is noticed by 

 Giimbel from the lower beds of the Greensand at Neukelheim (Bavaria) (see 

 Giimbel's Ostbayer. Grenzgeb., 1868, p. 764). 



On page 166 add — 



189«. Aeora cretacea, Conrad, from cretaceous beds at Iladdonfield, Xew 

 Jersey (sec above). 



On page 181 add to the synonyms of Eryphila lenticularis, (Goldf) — 



18G8- Bozyia Iciitirularis, Bosquet, Liste des foss. de mass. cr6t. du Limboui'g, p. 16, extr. du Dewalquus' 

 desc, gdolog. de Belgiijue. 



