322 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



TesseUa catena Ehrenb. Infus. 2(12, pi, 20 J. 7. 1838, not Ralfs, Ann. Mag. Nat. Hist, 



12: 104. pi 2, f, /.1843. 

 Diatonta arcuaimn Lyng. Hydro. Dan. ]80. pZ. 62, 1819? 

 Strialella arcuala C. Ag. Consp. 16.' 1832. Ralfs, Ann. Mag. Nat. Hipt. 11: 455. pi, 9. 



/ 6. ]843? not S. arcuata Ehrenb. Infus. 230. pL 20. f. G. 1838. 

 Rhahdonema arcvaium Kiitz. Bacill. 126. pi. 18, J. 6. 1844. W. Smith, Synop. Brit. 



Diat. 2: 34. pi. 38. /. 305 (not /. S05a'-h'. 1853). Cleve, Bih. Sv. Vet. Akad. 



Ilandl. 1'^: 24. pi 4J. 21, 1873. Pritch. Hist. Infu.s. ed. 4. 804. pi 10. f. 203-204. 



18G1. H. L. Smith, Sp. Diat. Typ. no. 433. ]874. Cleve & Moll, type no. C9. 



Schmidt, Atlas pi 220. f. 17-26, Grun, Vorh, ZooL Bot. Ges. Wicn 12: 423. 



1862. Van Hear. Synop. pi 54. f. U-16, 1881; Treat. Diat. 3G0./. 111. pi 12. f. 



487a. 1896. O'Meara, Proc. Boy. Irish Acad. IE 2: 318, not pi 29. f. 5. 1875, 



Rabh. Fl. Eur. Alg. 1: 306. 1864. De Toni, Syll. Alg. 2: 761. 1892. 

 SiriaLella crozierii Ehrenb. Mikrug. pi, 35 A. XXIII.f. 14-IG. 1854. 

 Rhabdonana crozierii Grun. Verli. Zool. Bot, Ges,Wi(ai 12: 423. 1862, not 7?. crozierii 



Ralfs in Pritch. Hist. Infus. ed. 4. 805. pi 4./. 43. 1861, nor H. L. Smith, Sp. 



Diat. Typ. no. 434. 1874, nor Schmidt, Atlas pi, 220 J, 3-11. 1899; pi 221. f. /-/a. 



1900. 



As will be seen by the above synonymy, tluTe is great confu.sion among the names 

 assigned to this diatom. As Cleve points ont," there is no important difference 

 between 7?, arcuatvm Kiitz. and Grunow's R, crozierii, based on S. croricm Ehrenb., 

 the simple difference of outline being of no account. But the R. crozierii of Ralfs 

 is an altogether different thing. It corresponds in its dilated center with the 

 variety of arcuatmti which Cleve calls variety vcnfricosnm;^ but in all other respects 

 it is unlike it. Probably, as Cleve states, it is reproduced by Janiscli^' and called R. 

 arcuatum., Wliereas R. arciiaium Kutz. and R. crozierii (Ehrenb.) Grun. has monili- 

 form striae or striae so nearly divided as to appear like a string of beads, the diatom 

 shown by Ralfs, H. L. Smith, and Schmidt has transverse costae bearing fine punctate 

 dots in a single median line^ and whereas the zonal divisions of the former are strongly 

 beaded, those of the latter are fintdy dotted with one or two rows of puncta. Habir- 

 shawf^ masses all these forms togetlier, wdth the result that he makes this species and 

 TesseUa arcuata Ehrenb. {= S iriatella , probably S, vnipvnctata) synonymous, an evi- 

 dent absurdity. 



I think Diatoma arcAiatvm- Lyngl>., and StriatcUa arencda C. Ag., arc* not the same 

 diatom; a question not relevant here, as neither can be safely identified witli this 

 species. My specimens are uniformly of the outline of Cleve*s variety ventri- 

 cosiiin, but with coarse beading on the valves and heavy markings (.>f the zonal septa, 

 as figured by Schmidt.^ 



Found at stations 3007, 3688II, 3712II, Bering and Okhotsk seas. 



TesseUa japonica (Temp. & Br.) Mann. 



Rhahdonema japonicum Temp. & Br, Mem. Soc. Pliys. et Hist. Nat. Geneva 30^: 



53. pi IJ, 0, 1889. De Toni, Syll. Alg. 2: 762. 1892. Schmidt, Atlas pi 218. 



/. 7-31, pi 219. f, 1-4, 6-12, 1899; pi 221. f. 24- 1900. 

 Rhahdonema mikado Pant. Beitr. Bacill. Ung. 3: pi S3.f. 469-470, 1893. Schmidt, 



Atlas pi 210. J. 2-4 (note). 1899. 



I have exandned a large number of specimens, compar( d with care all literature, 

 together with figures, to get a clear-cut and satisfactory basis for distinguishing between 



^Bih. Sv. Vet. Akad. Handl. 1^^: 24. 1873, 



&0p. cit. pi 4-f- 12. 



cRabh. Beitr. 1: 12. pi, 3.f, 19. 18G3. 



'^Hab. Cat. 301. 1877. 



e Schmidt, Atlas pi. 220. f. 21-22a, 1899. 



> 



