GR.NXDIDIERIA 105 1 



Hanncv'.din castcliiaiii Haas, Conch. Cab.. I'nio, 191 2, pi. 31, 



figs. 1 1- 1 2. 



"The Haniiandia castdneaiii differs from the somboricnsis 

 hy its sHghtly larger size and thicker valves; by its anterior end 

 not concave and almost oval, but short, straight, and with an 

 obtuse, conical point ; by its dorsal margin expanded in a large 

 angulated wing, not short and obliquely rounded ; by the great 

 lumiber of ribs, the anterior ones narrow, straight, granulated, 

 reaching the ventral margin, and not squamose and broken 

 in the central part by a deep groove : the posterior ones 

 oblique, large, projecting, with large, imbricated scales, not 

 finely granulated ; by the inter-costal space ornamented with 

 heavy, not fine, stria:? ; by the right cardinal tooth being oblique 

 and deepl}' sulcate. not pyramidal and sulcate on the inner 

 side ; by the lateral teeth, of which the anterior is verv short, 

 almost straight anrl not concave, and the lower straight and 

 not as long as the median ; and finally by the color of the nacre, 

 which is a very brilliant, bluish lead-color, not pure white." 



TTaas, (1. c), considers this a synonym of H. somboricnsis. 



Genus GR.WDTDTKRTA Bourguignat, 1885. 



Grandidicria J^oukouignat, JJuU. Soc. Mai. Fr., II, 1885, p. 6. 



Shell small, oval, rounded or rhomboid, solid, much inflated, 

 generally narrowly biangulate behind, often apparently of two 

 forms, one more inflated in the basal and post-basal parts than 

 the other; beal<s high, curved forward and inward and pointed, 

 very delicately and beautifully sculptured with zigzag lirae, 

 which become finely nodulous and sulcate on the disk, especi- 

 ally in front and behind ; posterior ridge well developed, often 

 slightly double ; hinge line curved ; two pseudocardinals in 

 the right valve separated by a parallel-sided socket, one or 

 two in the left, with often an irregular, triangular, ragged 

 tooth under the beak, which is frequently reflexed ; one ob- 

 liquely striate lateral in the right valve and two in the left ; 

 nacre of peculiarly soft, rich texture, white, coppery, or pur- 

 plish, delicately radiate ; beak cavities moderate ; muscle scars 

 distinct. 



Type, Unio hurtoni V\^oodward. 



