154 P. T. CLEVE, SYNOPSIS OF THE NAVICULOID DIATOMS. 



44. M. elegans Lewis (1865). — V. lanceolate, aubacute or subrostrate. L. 0,o66; B. 0,026 

 mm. Loculi 3 to 7 in 0,oi mm., delicate, frequently rudimentary, formiiig a band along the whole 

 margin. Median line almost straight, or very sligbtly undulating. Central area very small, or 

 indistinct. Striee about 15 in 0,oi mm. almost parallel througbout, punctate; puncta about 15 

 in 0,01 mm. forming longitudinal rows. — Proced. Acad. Nat. Se. Philadelphia 1865 p. 13 Pl. I 

 f. 9. — Grun. Foss. D. Öst. Ungarns p. 150 Pl. XXIX f. 20. A. S. Atl. CLXXXVI f. 19, 20. 



Marine: Atlantic coast of U. St.! Java! Pensacola! Foss. Bory, Hungary! 



45. M. paradoxa Grun. (1878). — V. linear-lanceolate, rostrate. L. 0,o55; B. 0,oi4 mm. 

 Loculi 4 in 0,oi mm. equal, forming a band at some distance from the margin, and ending at a 

 considerable distance from the extremities. Strise 26 to 29 in 0,oi mm. — Cl. M. D. Nio 153. 

 M. Seychellensis Grun. Casp. Sea Alg. p. 14. 



Marine: Corsica (Grun.), Seychelles (Grun.). 



This species is unknown to me, having failed in finding it in Cl. M. D. N:o 153. The 

 above description is from a sketch sent by Grunow, who does not indicate whether the strige are 

 longitudinal, straight, or oblique, for which reason its place in the system is uncertaiu. 



46. M. erythraea Grun. (1860). — V. lanceolate with aeuminate or apiculate ends. L. 0,o4; 

 B. 0,01 to 0,013 mm. Loculi about 12 in 0,oi mm., forming a band interrupted in one or two 

 places by one, to three, larger loculi. Median line undulating. Areas indistinct. Strite 21 inO,oi 

 mm. almost parallel, punctate; puncta forming undulating longitudinal rows, about 14 in 0,oi mm. 

 — Verh, 1860 p. 577 Pl. YII f. 4. M. J. 1877 p. 174 Pl. CXCIV f. 12 to 14. A. S. Atl. CLXXXVI 

 f. 25, 26. — M. hullata A. S. Atl. CLXXXVI f. 36 (1893). 



Marine: Mediterranean, Adriatic and Black Seas! Red Sea (Grun.), Honduras (Grun.), Ba- 

 hamas (Grove Coll.)! 



Var. hiocdlata Grun. (1877). — The larger loculi in the middle of the band. Strise 24 in 

 0,01 mm. — M. J. 1877 1. c. f. 15. 



Marine: Honduras (Grun.). 



Var.? itiierrupta Hantzch (1862). — Larger loculi 4 to 6. — M. inter. Hantzsch Ost Ind. 

 Arch. D. p. 20 Pl. VI f 5. A. S. Atl. CLXXXVI f. 37. 



Marine : East Indies (Hantzsch), Nicobar Islands (Grun ). 



47. M. coiistricta Cl. (1892). — V. elongated, with cuneate ends, constricted in the middle. 

 Ij. 0,06; B. 0,011 at the constriction 0,oo65 mm. Loculi 6 in 0,oi mm. of equal size and with 

 straight interiör margins. Median line undulating. Central area very small. Striée 21 in 0,oi 

 mm. transverse, punctate; puncta about 20 in 0,oi mm. forming undulating longitudinal rows. — 

 Diatomiste I p. 159 Pl. XXIII f. 5. 



Marine: Java! 



48. M. flexuosa Cl. N. Sp. — V. linear to elliptical with rostrate to aeuminate ends. 

 L. 0,0.1 to 0,045; B. 0,011 to 0,01 mm. Median line strongly sinuose. Loculi 7 to 8 in 0, 01 mm. 

 of equal size, quadrate, forming a band ending near the apices. Central area very small, orbicular. 

 StricB 16 to 20 in 0, 01 mm. parallel, of coarse elongated puncta, not forming straight lines. — 

 Pl. II f. 12. 



Marine: Pithyusian Islands! Mediterranean! 



This small species is remarkable for the strong flexure of its median line, near the central 

 nodule. 



49. M. ciispidata Cl. (1893). — V. elliptical, apiculate. L. 0,o26; B. 0,oi mm. Median line 

 strongly flexuose. Axial and central areas indistinct. Loculi 6 in 0, 01 mm. equal, quadrate, 

 forming a marginal band, ending below the extremities of the valve. Strite 25 in 0, 01 mm., pa- 

 rallel, not distiiictly punctate. — Diatomiste II p. 16 Pl. I f. 18. 



Marini': Bahamas (Grove Coll.)! 



