KONOL. SV. VET. AKADEMIENS HANDLINGAR. BAND 26. N:() 2. 87 



32. D. boiiibiforiuis Cl. N. Sp. — V. deeply eonstrioted in the midclle, witli broad seg- 

 ments. L. 0,03-2; B. 0,014 mm. Central nodnle small, its lini^ns strongly divergent. Furrows nar- 

 row. Costfe S in 0,ui mm. crossed by a longitndinal line. -- Pl. 1 f. 2(). 



Marine: Macassar Straits (di-dve Coll.)! 



Tliis form may be a small variety of D. Bowhus. 



33. D. Clepsydra Cl. N. Sp. — V. strongly eonstrioted, with almost orbicnlar segments. 

 L. 0,07; B. 0,0.32; at the constr. 0, 010 mm. Central nodnle large, quadrate; its liorns divergent in 

 the middle. Furrows narrowed in the middle and at the ends, crossed by faint costfe. Costas 7 

 in 0,01 mm. strongly radiate, alternating with single rows of alveoli. — Pl. I f. 29. 



Marine: Madagascar! 



34. D. Praestes A. S. (187.5). — Y. elongated, slightly constricted, with narrow elliptical 

 segments. L. 0,07 to 0,12; B. 0,019 to 0,025; at the constriction O,oi.'i to 0,oi7 mm. Central nodnle 

 small, qnadrate; its horns parallel. Fnrrows linear, moderately narrow. Costse almost parallel, 

 (i to 7 in 0,0 1 mm., alternating with rows of indistinct pnncta. — Nar. Prcestcs A. S. Atl. XII 

 f. .57, 58. 



Marine: Gnlf of JSTaples (Thuiii.)l Alexandria (Deby Coll.)! Red Sea (Deby Coll.)! Mazatlan 

 (Atl.). Campeaehy Bay (Atl.). 



D. Frästes is nearly allied to D. Guinardiana, from whieli it diffe]\s by somewhat coarser 

 costte and the rows of alveoli alternating with the costcE. It seems to be very probable that 

 D. Guinardiana is only a corroded D. Presstes. 



35. D. Eutomon (Ehb. 1844) A. S. — V. elongated, slightlji- constricted in the middle, with 

 tongne-sliaped segments. L. 0, 072 to 0,15; B. 0, 028 to 0,042; at the constr. 0, 020 to O, .35 mm. 

 Central nodnle large, qnadrate, its horns parallel. Furrows moderately wide, linear, forming a space 

 of abont a third of the width of the valve, often dilated aronnd the central nodnle. Cost?e 6 to 8 

 in 0,0 1 mm. parallel, at the ends divergent, anastomosing with a few (1 to 4) longitndinal, irregnlarly 

 nndnlating, more or less distinct, costffi. — Dijjl. Entomon Ehb. Berl. Ber. 1844 accord to Cha.se. 

 Na.r. Entomon A. S. N. S. D. Pl. 1 f. 13, 14; Atl. XIII f. 48, 49. Nav. lomboides var. media Grun. 

 A. D. p. 41 Pl. III f. 54. Nar. homhoidcs A. S. Atl. XIII f. 38. 



Marine: Arctic America! Spitsbergen! Kära! Finmark! North Sea! Mediterranean Sea! 

 Adria! Samoa! Sidney! China! Japan! Behrings Island! Mexillones, Peru (Deby Coll.)! Fossil: 

 Brttnn, Tegel! Bory, Hungary! 



1). Entomon is not a sharply defined species, graduating as it seems into J). spJcndida, with 

 which many of its varieties are closely connected. 



36. D. spleiitlida Greg. (1856). — V. elongated, panduriform. L. 0,or)r) to 0,22; B. 0,u2 to 

 0,05; at the constr. 0,oi.t to 0,0.3 mm. Central nodnle large, quadrate; its horns parallel. Furrows 

 narrow, linear, not dilated aronnd the central nodule. Transverse costte 5 to 8 in 0, 01 mm.; crossed 

 011 each side of the median line by 4 to 6, slightly curved or nndnlating longitndinal costse. — 

 Na^v. splendida Greg. T. M. S. IV p. 44 Pl. V f. 14. V. H. S. Pl. IX f. 4. A. S. N. S. D. 

 Pl. I f. 3, 4, Pl. II f. 2. Atl. XIII f. 31, 32, 34. Nar. Entomon Donk. B. D. p. 49 Pl. VII f. 5. 

 Nav. (lidyma var. Greg. T. M. S. IV p. 45 Pl. V f. 16. Nav. gcmmatida Cl. Qneb. M. Cl. II (2) 

 p. 167 Pi. XII f. 1 (1885). Nav. Tasclienhergeri A. S. Atl. CLXXIV f. 9; 1892 (a large and coarse 

 form). N. margaritifcra Pant. III Pl. XXXV f. 494 (1893)? 



Marine: Greenland! Spitsbergen! Beeren Eiland! Finmark! North Sea! Ceylon! Madagascar! 

 Java! Sumatra! Port Jackson! Japan! Sandwich Islands (Atl.). West Indies! Florida! Fossil: 

 Moravian Tegel! S:a Monica, Calif.! 



