AUT.^3 FRESH- WATER MUSSELS^ ANODONTITES MARSHALL H 



illustrations than were possible in Bruguiere's time, the species 

 deserves a fuller description than has ever been given it. The fol- 

 lowing is therefore offered: 



ANODONTITES CRISPATA Bruguiere 



Shell elongate-ovate, rather compressed and thin. Anterior end 

 narrower, rather abruptly rounded, obliquely fading into the ventral 

 margin. Posterior end broader, obliquely truncate above to a rib on 

 the posterior dorsal area, then rounding into the ventral margin with- 

 out angle. A shallow depression across the disk from beak to near the 

 middle of the ventral margin. Ventral margin nearly straight, very 

 faintly incurved at its middle portion and slightly gaping in that 

 region. Posterior dorsal ridge rounded; above it a rather strong 

 rib running across the dorsal area from the beak to the posterior 

 margin. Sculpture of many festoons arranged to form a beautiful 

 sculpture, winch is distinct both radially and concentrically. Kadi- 

 ating from the beaks to the margins are many apparent sulci, but 

 they are formed by the festoons being arranged on the background in 

 radiating units, the space between each adjoining unit seeming to 

 be cut into the surface. The sculpture is less pronounced and some- 

 Avhat confused on the anterior and posterior areas. Color nearly 

 uniform light chestnut. Interior not very iridescent, bluisii white, 

 the nacre appearing to be radiately striate. Anterior adductor scar 

 moderately deep, the posterior scar superficial. Sinulus distinctly 

 triangular, its lower end slightly hooked. Prismatic border rather 

 narrow. Pallial line scarcely visible. U.S.N.M. No. 86402. Length, 

 32 mm. Height, 20 mm. Diameter, 10 mm. Cayenne, French 

 Guiana. Lea collection, from Ferussac. 



In the above specimen the microscopic radiating striae described 

 by Marshall ^° as being generally characteristic of Anodontiteii and 

 some other genera show only as faint traces here and there, as they 

 seem to have been scuffed off. The striae figured in that paper on 

 Plate 1, figure 1, do not belong to crisyata but to a specimen of luteola 

 Lea, which had been wrongly identified. 



In the foregoing description the three features of most importance 

 are: (1) The triangular sinulus, which was not mentioned by 

 Bruguiere; (2) the locality Cayenne, French Guiana, as Bruguiere's 

 type came from " les rivieres de la Guyanne"; and (3) the peculiar 

 sculpture, which proves that the specimen is of the species anspata 

 and that Ortmann was mistaken in his identification of this species 

 in his Carnegie paper of 1921. 



Anodonta puherula Gould, of which the type is in the United 

 States National Museum (No. 5933), resembles crispata in form, but 



»oproc. U. S. Nat. Mus., vol. 67, art. 4, pp. 1-14, pis. 1-4, 1925. 



