NO. 1205. SYNOPSIS OF THE NAIADES—SIMPSON. 933 



*Anodonta aperta Eafinesque, Atl. Jl.,No. 4, 1832, p. 134. 

 Parana Eiver, South America. 



* Anodonta atrovireus Philippi, Zeits. fiir Mai., V, 1848, p. 130. 

 ""Anodonta carinata DUNKER, Mai. BL. V, 1858, p. 225. 



Colombia. 



^Anodonta cornea Philippi, Zeits. fur Mai., V, 1848, p. 130. 

 Nicaragua. 



* Anodonta giuUaini H. and A. Adams, Gen. Eec. Moll., II, 1857, p. 502. Credited to 



Recluz. 



* Anodonta lyaphos Eafinesque, Atl. Jl. and Friend., 1832, p. 134. 



Parana Eiver. 



^Anodon pictiis Swainson, Ex. Conch., 2d ed., 1841, p. 39. 



''Anodonta wallisi MoussoN, Mai. BL, XVI, 1869, p. 188. 



"Anodonta tehnaniepecensis Fischer and Crosse, Miss. Sci., 1894, p. 526. 



Tehuantepec. Not yet figured. 



^Anodonta hertwigi VON Ihering. 

 Where? 



* Anodonta hergi VON Ihering. 



Where? 



Genus MYCETOPODA d'Orbigny, ISSS.^ 



(Type, My cetopoda soleniformis ^''Ovhignj.) 



Mycetopoda d'Orbigny, Guer. Mag., No. 62, 1835, p. 41. 

 Mycetopus d'Orbigny, Voy. Am. Mer., 1847, p. 600. 



Shell thin, elongated, truncate above behind, with a low, posterior 

 ridge and rather flat, smooth or slightly concentrically wrinkled beaks; 

 epidermis smooth, shining, pale greenish-yellow or brownish, rayless; 

 hinge line long, straight, edentulous or showing faint traces of denticles, 

 under a glass, beneath the nacre; nacre soft, bluish- white and irides- 

 cent; muscular impressions faint, irregular, the smaller anterior scar 

 above the larger one; beak cavities shallow. 



Animal having very long gills, the inner much the larger, united to 

 the abdominal sac throughout their whole length; palpi large, round 

 below, xH'ojecting very slightly behind and attached along the whole 

 length of the straight upper border; mantle very thin, slightly thick- 

 ened at the edges; branchial opening closed below into a short papillose 

 siphon, and separated from the nearly smooth anal opening by a strong 

 bridge; suj)eranal opening not closed below; foot very long, developed 

 at the lower end into a sort of head or button. 



' So named by its author in the Guerin Magazine, but afterwards changed by him 

 to Mycetopus in the Voyage Amerique Meridionale. The genus has been made the 

 type of a separate family by Gill, and was so acknowledged by Pelseneer and others, 

 but it does not seem to me to be separable from the Mutelidce. Certain shells under 

 favorable light show slight dentilations along the hinge line, which are, no doubt, 

 Yestigial taxodont teeth common to the family ; the labial palpi and anal bridge are 

 decidedly mutelid in character, and the great development of the foot is paralleled 

 in Solenaia, Lastena, and to some extent by Gonidea among the Unionidw. 



