86 NILS HJ. ODHNER, STUDIES ON RECENT CHAMIDAE. 



end of the adductor. These facts are left out of consideration by Anthony. He 

 pays attention to the similarity in the disposition of the mantle slits, an arrangement 

 common to other genera such as Cypricardia, Isocardia, Chamoslrea, and to the gills, 

 which have also a similar construction in different familiae. »La branchie de la 

 Chame est tres semblable ä celle d'un Cardium», says Anthony (p. 325). But the 

 gill of Chama shows also a striking agreement with that of other genera. Its struc- 

 ture as a plicated synaptorhabdic gill, showing alternately high and low interlamellar 

 septa, is shown in many other forms e. g. Mya (Vlés 1909), and the resemblance 

 to Cardium is not at all greater than to Veneridae. The marginal furrow of the 

 anterior demi-branch, which Anthony considers as supporting his opinion, is present 

 in many different genera of Lamellibranchia (ef. above p. 64). The gills must, con- 

 sequently, be employed only with caution as evidence of a closer relation. 



Anthony finds further support in the intestinal canal. »Le tube digestif des 

 Chames est par rapport å celui du Cardium edule et du Cardium norvegicum, ou nous 

 1'avons étudié, extrémement simple. Mais cette consideration ne suffit pas pour 

 éloigner les Chames des Cardiidae, chez lesquelles d'une espéce a 1'autre les plus 

 grandes variations existent dans la disposition du tube digestif» (p. 325). That the 

 simple intestine of the Chamidae should be derived from the spirally coiled one of 

 Cardiidae is, however, hardly likely, though in other respects there are agreements 

 between both families, e. g. in the simple duodenal portion without freely depending 

 crystalline sac. 



Of the excretory and the genital organs Anthony" only says that they »n'offrent 

 rien de particulier chez les Chames». 



Such are the arguments that Anthony brings in favour of an anatomical rela- 

 tion between the Chamidae and the Cardiidae. All contributions to a comparative 

 investigation and to a comprehension of the relations based on the anatomy are 

 certainly needed, and Anthony's researches have thrown light upon many problems, 

 but his reasons in support of an agreement between Cardiidae and Chamidae are far 

 from convincing. The arguments that he has been able to deduce from the sculp- 

 ture and the construction of the shell are also few. Of the sculpture ha says (p. 

 324): »Sur les Chames adultes 1'ornementation est difficilement caractérisable . . . 

 Sur les formes jeunes au contraire non encore fixées, les ornements sont tres spéci- 

 aux et se rapprochent infiniment de ceux que 1'on rencontre å 1'état adulte chez 

 certains Vénéridés, comme s'accordent a 1'affirmer Jackson, F. Bernard et moi- 

 méme; ils n'ont aucun rapport avec 1'ornementation des Cardiidés ainsi que Dou- 

 villé en fait la juste remarque. » But in the next sentence the author finds that 

 the hinge supports an opposite view: »Mais la dentition des jeunes Chames se rap- 

 proche absolument de celle des Cardiidae adultes, et plus particuliérement de celle 

 du genre Lithocardium, chez lequel comme chez les Chames la dent latérale antérieure 

 a disparu.» 



Such are the proofs of a relation between Chamidae and Cardiidae which 

 Anthony deduces from the characters of the shell. The hinge does not, however, 

 agree with that of Cardiidae as closely as Lithocardium would prove. It is true that 



