KONGL. SV. VET. AKADEMIENS HANDLINGAU. BAND 27. N:o 3. 169 



radiate and distinctly pimetate. Marginal area narrow. — T. M. S. IX p. 73 Pl. VIII f. 19. 

 A. S. Atl. CXCIII, 34. Icon. n. Pl. II f. 36, 37. C. distans Greg. D. of Clyde p. 490 Pl. IX 

 f. 23 (1857). Pritch. Inf. Pl. VII f. 38. C. rer/alis Per. D. de Villefranche p. 37 Pl. II f. 12? 



Marine: Coasts of Scotland (Greg, Grrev.) and Norway! Balearic Islands! Galapagos Islands! 



2. C. Pediculus Ehb. (1838). — Outline broadly elliptical, frequently subrhomboidal or 

 malformate. L. 0,oi5 to 0,03; B. 0,oi to 0, 02 mm. Upper V. with a linear, axial area somewhat 

 con.stricted in the middle. Strite 17 to 18 in 0, 01 mm. finely punctate; pnncta forming undulate, 

 longitudinal rows. Lower V. freqnently with traces of a loculiferons rim. Axial area indistinct. 

 Central area small, suborbicnlar. Strite 16 to 17 in 0, 01 mm. finely punctate, radiate, not reaching 

 to the margin, where is a hyaline, narrow rim. Annulns with rudimentary loculi. — Inf. p. 194. 

 Pl. XXI f. 11. W. Sm. b. D. i Pl III f. 31. V. H. Syn. p. 133 Pl. XXX f. 28 to 30. A. S. 

 Atl. CXCII, 56, 58 to 63. Cocc. sigmoidea Schdm. P. D. II Nachtr. Pl. I f. 14? O. tenera Schum. 

 II Nachtr. p. 54 f. 15? C. Placentula var. haltica Dannf. p. 14 Pl. I £ 1 (1882)? C. excentrica 

 G-UTW. Mäter. p. 27 f. 22? 



Fresh or brackish water: throughout Europé! Baltie! Caspian Sea (Grnn.)! Michigan! 

 Ecuador ! 



Var. Salinarum Pant. (1889). — L. 0,021; B. 0,012 mm. Strise of the lower valve 25 in 

 0,01 mm. — Pant. II p. 58 Pl. XXVII f. 393. 



Brackish water: Hungary, fossil (Pant.). 



3. C. Placentula Ehb. (1838). — Ontline elliptical. L. 0,oi25 to 0,035; B. 0,oo8 to 0,02 

 mm. Upper V. with narrow, linear, not constricted, axial area. Strife 25 in 0, 01 mm. finely 

 punctate; puncta forming undulate, close longitiidinal rows. Lower V. with distinct marginal 

 line, frequently also a loculiferons rim (loculi 15 in 0, 01 mm.). Median line straight, not reaching 

 to the ends. Strife 23 in 0,oi mm. — Inf. p. 194. W. Sm. B. D. I Pl. III f. 32. V. H. Syn. p. 133 

 Pl. XXX f. 26, 27. A. S. Atl. CXCII, 38 to 51. C. punctata Schdm. Tatra D. p. 60 Pl. II f. 20. 

 C. producta A. S. Atl. CXCI, 2. 



Eresh or brackish water: throughoi;t Europé! Baltie! Caspian Sea (Grun.), Tasmania! New 

 Zealand! Illinois! California! Mexico! Ecuador! 



Var. intermedia Hérib. a. Pebag. (1893). — L. 0,o5 to 0,o7 mm. Upper V. with coarser 

 rows of puncta, 12 (margin) to 15 (axial part) in 0,oi mm. — C. intermedia Hérib. a. Perag. D- 

 d'Auvergne p. 44 Pl. III f. 1, 2. 



Fresh water: Puy de Dome, fossil. 



Forma minor Hérib. a. Perag. 1. c. L. 0,02 to 0,o3 mm. 



Fresh water: Puy de Döme, fossil. 



Var Bouxii Brun a. Hérib. (1893). — L. 0,04 to 0,09; B. 0,025 to 0,055 mm. Upper V. 

 with coarse strise, about 14 in O, o 1 mm. crossed on each side of the axial area by 5 to 6 blank 

 undulating bands. Lower V. with about 14 striee in 0,oi mm. Their puncta about 16 in 0, 01 

 mm. — C. Rouxii Br. a. Hérib. D. d'Auvergne p. 45 Pl. I f. 3. 



Fresh water: Anvergne, Puy de Dome fossil and living. 



Var. trilineata Hérib. a. Perag. (1883). — L. 0,02 to O.025; B. 0,oi to 0,oi3 mm. Upper 

 V. with about 16 stx^iee in 0, 01 mm. crossed by 3 broad longitudinal, blank bands. Lower V. with 

 15 to 17 strise in 0,oi mm. — C. trilineatus Hérib. a. Perag. D. d' Anvergne p. 47 Pl. III f. 4, 5. 



Fresh water: Puy de Döme fossil. 



Var. lineata Ehb. (1843). — L. O.04 to 0,07; B. 0,03 to 0,04 mm. Strise of the upper valve 

 punctate, puncta forming 4 to 6 longitudinal, undulating rows. Strife of the lower valve 17 in 0, 01 

 mm. — C. lineata Ehb. Am. p. 81. V. H. Syn. p. 133 Pl. XXX f. 31, 32. C. Un. var. minor 

 Pant. III Pl. XXI f. 311 (1893). C. Un. var. pygmea Pant. 1. c. Pl. VIII f. 140. 



Fresh water: Belgiiim (V. H.), Mexico, Oregon, Guatemala, foss.! 



K. Sv. Vet. Akad. Hand). Band 27. N;o 3. 22 



