KONGL. SV. VET. AKADEMIENS HANDLINGAU. BAND 27. N:0 3. 169 



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

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

 f. 23 (1857). Pritch. Inf. PI. VII f 38. C. regalis Per. D. de Villefranche p. 37 PL II f 12? 



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



2. C. Pediculus Ehb. (1838). — Outline broadly elliptical, freijuently subrliomboidal or 

 malformate. L. 0,oi5 to 0,03; B. 0,oi to 0,0 2 mm. Upper V. with a linear, axial area somewhat 

 constricted in the middle. Strise 17 to 18 in 0,oi mm. finely punctate; puncta forming undulate, 

 longitudinal rows. Lower V. frequently with traces of a loculiferous rim. Axial area indistinct. 

 Central area small, suborbicular. Strise 16 to 17 in 0,oi mm. finely punctate, radiate, not reaching 

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

 PI. XXI f. 11. W. Sm. B. D. I PI III f. 31. V. H. Syn. p. 133 PL XXX f. 28 to 30. A. S. 

 Atl. CXCII, 56, 58 to 63. Cocc. sigmoidea Schum. P. D. II Nachtr. PL I f. 14? G. ienera Schum. 

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

 Gdtw. Mater, p. 27 f. 22? 



Fresh or brackish water: throughout Europe! Baltic! Caspian Sea (Grun.)! Michigan! 

 Ecuador ! 



Var. Salinarum Pant. (1889). — L. 0,02i; B. 0,oi2 mm. Striee 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). — Outline ellipticaL L. 0,oi25 to 0,035; B. 0,oo8 to 0,02 

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

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

 line, frequently also a loculiferous rim (locvili 15 in 0,oi mm.). Median line straight, not reaching 

 to the ends. Strise 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 Schum. Tatra D. p. 60 PL II f. 20. 

 G. producta A. S. Atl. OX CI, 2. 



Fresh or brackish water: throughout Europe! Baltic! Caspian Sea (Grun.), Tasmania! New 

 Zealand! Illinois! California! Mexico! Ecuador! 



Var. intermedia H^rib. a. Pbrag. (1893). — L. 0,05 to 0,o7 mm. Upper V. with coarser 

 rows of puncta, 12 (margin) to 15 (axial part) in 0,oi mm. — C. intermedia H^rib. a. Peras. D- 

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



Fresh water: Puy de Dome, fossil. 



Forma minor H^rib. a. Perag. 1. c. L. 0,02 to 0,o3 mm. 



Fresh water: Puy de Dome, fossil. 



Var Rouxii Brun a. H6rib. (1893). — L. 0,04 to 0,o9; B. 0,o25 to 0,o55 mm. Upper V. 

 with coarse striae, about 14 in 0,oi mm. crossed on each side of the axial area by 5 to 6 blank 

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

 mm. — G. Botixii Br. a. H^rib. D. d'Auvergne p. 45 PL I f. 3. 



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



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

 V. with about 16 strise in 0,o 1 mm. crossed by 3 broad longitudinal, blank bands. Lower V. with 

 15 to 17 strise in 0,oi mm. — G. trilineatus HfeiB. a. Perag. D. d'Auvergne p. 47 PL III f. 4, 5. 



Fresh water: Puy de Dome fossil. 



Var. Uneata Ehb. (1843). — L. 0.04 to 0,07; B. 0,03 to 0,04 mm. Strise of the upper valve 

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

 mm. — G. Uneata Ehb. Am. p. 81. V. H. Syn. p. 133 PL XXX f. 31, 32. C. lin. var. minor 

 Pant. Ill PL XXI f. 311 (1893). G. lin. var. pygmea Pant. 1. c. PL VIII f. 140. 



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



K. Sv. Vet. Akad. Handl. Band 27. N:o 3. 22 



