UNIO.— Plate XCV 



Species 



30. (Mus. Ha 



Unio crassus. Uh. tedci xulidd, sitbveiilricusu, ovutii, 

 iiiaquilaterali, oUvaceo-luted, tenebroso-B'tridi niidiijiie 

 late radiald, nuhlavigatd, riigk increineiill tautnui 

 xciUptd; margine ven/raii aubarciiato, aidici acclivi ; 

 codd umbouali ohtme subangulatd ; and podlcd dor- 

 mli satis ungustd ; umhonibus erosis, satis emine/ttibiis ; 

 hiiiidd magna ; manjaritd albd ; dentibus cardinalibm 

 I'vectis (2 et 3), trigoiiis ; lamelLis lateralibus ealidis, 

 obliqids, subrectis. 



The thick Unio. Shell solid, ventrioose, ovate, inequi- 

 lateral, olivaceous-yellow, evei'yvvbero broadly rayed 

 witli dusky green, smootliisli, iiirrely marked hy the 

 u'rinklts of increase ; ventral eiliic -niiirwhat arcuated. 



