MYCRTOPODA 1459 



narrowly rounded, ending' in a blunt point at the base of the 

 shell ; hinge line straight ; base line straight or slightly in- 

 flated medially ; anterior end narrowed and rounded ; poste- 

 rior end decidedly obliquely truncate ; surface with irregular 

 growth lines, often with inconspicuous radial sculpture ; epi- 

 dermis ashy-green, often llushed with brown, shining; nacre 

 bluish-white. 



Length 100, height 2>7^ diam. 18.5 mm. 



Length 115, height 39, diam. 20 mm. 



Bolivia, Brazil: south into .Argentina. 

 Anodon siliqnosiis Spix, Test. Fluv. Bras., 1827, p. 30, pi. 



XXIII, fig. 2. 

 Mycetopus siliquosus H. and A. Adams, Gen. Rec. Moll., II, 



1857, p. 505; III, pi. cxviii, fig. I. — SowERBY, Conch. Icon., 



XVI, 1868. pi. r, fig. 2; HI, fig. 2a. — Clessin, Conch. Cab. 



Ano.. 1875, p. 200, pi. Lxviii, figs. 2-4; LXix, fig. I. 

 Platiris (Mycetopus) siliquosus Lea, Syn., 1852, p. 56; 1870, 



p. 90. 

 Platiris (Iridina) siliquosa Lea, Syn., 1836, p. 56; 1838, p. 34. 

 Anodonta siliquosa Kusteu, Conch. Cab. Ano., 1853, p. 35, pi. 



VI IT, fig. 3. 

 Mycetopoda siliquosa Chenu, 111. Conch., 1858, pi. i, figs. 2, 



2a, 2b, 2c. — Simpson, Syn., 1900, p. 934. 

 f Anodonta legumcn \'ox AIartens, S. B. Nat. Fr., 1888, p. 65. 

 Glaharis legumen Simpson, Syn., 1900, p. 932. 

 Mycetopoda legumen von Ihering, Abh. Senckenb. Ges., 



XXXII, 1910, p. 120. 

 Mycetopus clessini von Ihering, Arch. f. N^aturg., 1893, p. 57. 

 Mycetopoda clessini von Iheking. Abh. Senckenb. Ges., 



XXXII. 1910, p. 120. 



This seems to be a variable form approaching closely in 

 some cases to M. occidentals, but is less inflated, more elon- 

 gated, has a straight hinge line and is more obliquely truncate 

 posteriorly. It is quite probable that it runs into M. subsin- 

 nata. The clessini of von Ihering is the same as Sowerby's 

 figure of siliciuosa on pi. iii, fig. 2a. 



