JUKES-BKOWXE : SYNOPSIS OF THK TENEllID^. 93 



Venenipis, s.s. Type as above. Shell with radial riblets crossed 

 by distant concentric ridges. Escutcheon defined by a ridge in the 

 left valve. Pallial sinus generally short, subangular, and ascending. 



Clandiconcha, Fischer, 1887. Type, V. monstrosa, Chem. 



Shell very irregular and iuequivalve, the posterior margin of the 

 right valve so expanded as to overlap that of the left. Escutcheon 

 not defined. Pallial sinus variable. 



The typical section of T'eneriip is includes V. elegans, Desh., V. exotica, 

 Lam., V. hmiellifera, Conrad, V. crenata, Lam., V, carditoides, Lam., 

 V. planicosta, Desh., V. initis, Desh., V. pidcherrima, Desh., and 

 possibly V. diemenensis, Q,. & G. 



Clandiconcha includes V. cumingi, Desh., and V. ntadreporica, Jonas. 



Suh-genus. 



Pullastra, Sowerby, 1826. Type, T'enus puUastra, Mont. 



Shell witli shallow radial or corrugated concentric sculpture. 

 Escutcheon not defined. Pallial sinus large and deep, sometimes 

 touching the pallial line below. Pedal scar separate. 



The other species are JP. geograjjhica. Lam., F. fahagella, Desh., 

 P.galactites, Lam., P. corrngata, Chem., P. cumingi, Sow., P. disrupta, 

 Sow., and ? P. dactyloidts. I see no i-eason for separating the four 

 lust as a distinct section under the name of J/yr«?<s (Adams) ; some 

 specimens of P. pullastra are nearly as rough as corrugata, and the 

 pallial sinus varies both in depth and width. Moreover, two species 

 generally assigned to Venenipis, viz. V. rngosa and V. siliqua, have 

 a deep rounded pallial sinus, and are better placed under Pullastra 

 than under Venerupis. 



Genus Baeoda, Stoliczka, 1871. 



The separation of this genus from 2\ipes was advocated by me in 

 1908,^ and at the same time I pointed out the close resemblance 

 between the hinges of Baroda and Venerella, the former being 

 a Cretaceous fossil and the latter being small oval shells found in the 

 Eocene of the Paris Basin. I see no reason to alter the opinion then 

 formed, because the similarity of the dentition is to my mind of more 

 importance than the dissimilarity of shape ; but those who think 

 otherwise will doubtless agree with M. Cossmann in placing Venerella 

 near Mercimonia. On my view the following is a comprehensive 

 generic description. 



Shell oblong or oval, concentrically striated, and sometimes also 

 radiately ribbed. Lunule superficial. Escutcheon not defined. Hinge 

 with three entire teeth in each valve, even the right posterior being 

 entire and very narrow. In the right valve the anterior and median 

 are placed under the umbo and directed forward, while the posterior 

 is directed backward, so that there is a wide space between it and the 

 median with an excavated border. In the left valve the teeth are 

 more equally divergent, and the plate is excavated between each of 

 them. Valve-margins smooth. 



' Proc. JMalac. See, vol. viii, p. 171. 



