906 PBOCEEDINGS OF THE NATIONAL MUSEUM. 



The following are uiifigured Mutelas: 



""Mutela lavigerina Bourguignat, Un. and Ir., 1886, p. 26. Lake Tanganyika. 

 *Mutela moineti Bourguignat, Un. efc Ir., 1886, p. 27. Lake Tanganyika. 

 ""Mutela suhdiaphana Bourguignat, Moll. Fluv. Ny., 1883, p. 5. Victoria K yanza. 

 *Muielina thoftoni Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 7. Kongo. 

 *Mutelina lecjumen Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 6. Kongo. 

 ''Mutelina maUlli Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 7. Kongo. 

 *Mutelina paludicola Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 8. 

 ""Mutelina xwas'ma Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 7. Kongo. 



* IridinawehvitscUi Morelet, Voy. de Angola, 1868, p. 98. 



Genus CHELIDONOPSIS Ancey, 1887. 



(Type, Chelidoneiira arietina Eocliebruue. ) 



Chelidoneura Eochebrune, S. B. Nat. Fr., 1886, p. 3. 

 Chelidonopsis Ancky, Conch. Esckange, II, 1887, p. 22. 



Shell elongated, thin, narrowed in front, gaping on the anterior basal 

 jjart and winged on the front dorsal j)ortiou, rounded behind, with a 

 pinched-up posterior ridge which develops into an open or closed tube 

 near its hinder part; the shell ending in a diamond-shaped gap; 

 epidermis shining slightly, concentrically grooved ; hinge-line narrow, 

 straight, with faint vestiges of denticles; a deep furrow inside marks 

 the position of the posterior ridge; muscle scars faint; nacre brilliant, 

 iridescent. 



Animal unknown. 



CHELIDONOPSIS ARIETINA Rochebrune. 



* Chelidoneura arietina Eochebrune, Bull. Soc. Mai. Fr., Ill, 1886, p. 4, pi. i, figs. 



1-4. 



Gancini, Kongo. 



t CHELIDONOPSIS HIRUNDO von Martens. 



* Spatha Mrundo VON Martens, S. B. Nat. Fr., 1881, p. 122; "Conch. Mitth., Ill, 



1885 f, p. 139, pi. xxvii; 1 Conch. Mitth., II, 1883, p. 139, pi. xxvii. 



* Spatha {Mntela) Mrundo Eochebrune, Bull. Soc. Mai., Fr., Ill, 1886, p. 2, pi. i, 



figs. 5, 6. 

 Chelidoneura hirundo VON Martens, S. B. Nat. Fr., 1886, p. 161, pi. i, figs. 5, 6. 



Kongo region. 



Genus BRAZZ^^A Bourguignat, 1885. 



(Type, Brazzwa anceyi Bourguignat. '-) 



Brazzwa Bourguignat, Esp. Nouv. et Gen Nonv., 1885, p. 321. 



Shell thin, transparent, brilliant wine-colored, elliptical, greatly 

 inflated, with a vSlight post-dorsal wing, and a high double posterior 

 ridge; beaks smooth, compressed, but the region below them full; 



' Prohahly the young of arietina. 



2 This appears to he a valid genus, helonging to the Mutelidw. I copy for the most 

 part Bourguignat's description, which leaves out some essential characters. I have 

 neA^er seen any of the species. 



