— 429 - 



1, Lithodomus lithopliagus Linne. T. valde in- 

 Hata, solida, subcylindrica , utrinque rotuiidata, postice latior, 

 striis incrementi concentricis subtilibus parteni posticam versus 

 fortioribus instructa; basis paene rectilinea; dorsum medium 

 paululum fornicatum et carinatum; umbones ab extremitate 

 antica remotiusculi ; epidermis castanea, parte antica et dorso 

 exceptis striis directis insignita. — Long. 60 — 100 Mm. Dunker. 



Mytilus lithopliagus Linne ed. 12 p. 1156. — (Mod.) Lam. VII 

 p. 26. - Pbilippi Enum. I p. 71. Abbild II p. 147 T. 1, F. 7.— 

 (Lithod.) PajTaudeau Corse p. 68. — Eeeve Conch. icon. sp. 9. — 

 Weiukauff Mittelm. p. 221. — Chenu Manuel II F. 771. 



Callitriche lithodoma Poli Test. Sicil. I p. 194. 



Lithodomus dactylus Cuvier Regne animal II p. 471. — Sow. Geu. 

 F. 1. 2. 



Lithophaga lithoglypha Meuschen Mus. Gronov. fide Morch Cat. 

 Yoldi p. 55. - Dunker in Mart. Ch. II p. 3 T. 4, F. 5. 6. 

 Var. = L. inflatus Requien Corse p. 36. 

 Hab. mare mediterraneum. 



2. Litliodoraus aristatus Solander. T. subcylin- 

 dracea, tenuis, antice tumida rotundata, postice producta, atte- 

 nuata et compressiuscula ; umbones parvuli^ lateriantico approxi- 

 mati; epidermis luteo-fusca, crusta calcarea obducta, postice 

 appendicibus rostriformibus obliquis terminata. — Long. 25 Mm. 

 Dunker. 



Mytilus aristatus Solauder mss. — Dilhvyn Descr. Cat. I p 303. — 



(Lith.) Weiukauff Mittelm. p. 222. — Carpenter Mazatlan p. 126. 



— Lischke Japan II p 126. — Dunker in Mart Ch. II p. 14 



T. 6, F. 15. 

 Modiola caudigera Lamarck VII p. 27. — Sow. Gen. F. 4. — Philippi 



Abbild. II p. 149 T. 1, F. 5. - Reeve Conch. ic. sp. 16. 

 Le Ropau Adanson Coq. Senegal p. 267 T. 19, F. 2. 



Hab. mare mediterraneum. — In maribus calidioribus fere 

 ubique invenitur. 



7. Genus Idas Jeffreys. 



T. transverse oblonga, rhomboidea, arciformis, tenuis, 

 margaritacea, inaequilatera ; hgamentum externum ; margo car- 

 dinalis fere rectus, subangulosus, antice et postice subtiUssime 

 denticulatus ; epidermis pilosa. 



Idas argenteus Jeffreys. T. irregulariter trapezoidea, 

 tenuis, subopaca, striis radiantibus concentricisque subtilissime 

 reticulata, argentea, ad umbones rufo-fusca; margo dorsahs et 

 ventralis recti, anticus rotundatus, posticus declivis; uinbones 

 rotundati, incurvati, margini antico approximati; cardo dentibus 

 numerosis; margo haud crenulatus, impressiones musculares 

 inconspicuae. — Long. 4, alt. 2 Mm. Jeffreys angl. 



Idas argenteus Jeffreys Ann. Mag. 1876 Nov, p. 428. — Pr. Z. S, 



1879 p. 570 T. 45, F. 3. 



Hab. in abyssis oceani atlantici. 



