358 COKTRTBUTIONS FROM THE NATIONAL HKRBAKIUM. 



This is [>r()l)al>ly disliurl from X (lulijma (Ehrcnlt.) Kilt/.., tluni^^li it closely ap- 

 proaches Donkiii's fi^niru of thai spt'cu\s.''^ I look upon this ivtieinliluncu as mucli 

 inor(^ ylrikiiiy than that l>etwe('ri the presuut species and .V. didyma fEhrenl).) K(itz.,^ 

 as suggested l>y Grunow.*^ Grunow's own figures of this spori(^s are a cpiite dilTenMit 

 thing, and agree more closely with the diatom 1 have named N. piwjuis; see under 

 tliis for fuller discuifsiun. O'Meara^Ms careless in calling this N. subdtUa on his 

 plate, an<l his figure is inexcusably had. 



Found at station 3008II, Hawaiian Islaiids, 



Navicula undata Mann. sj). nov. Plate LIII, ih(;uue 1. 



A^alvean elongated ellipse, with hhmt apices, the sides scarcely curved until about 

 half way between the center an<l tlie ends, tln^ice the curvature nun\t pntuounced for 

 a short distancCj and finally the si<leH nearly straight to the l)road an<l blunt apict^s; 

 markings of coarse beading of th<' N. aspera type, hut tlie beads round, not oval, 

 arrang(^d in oblique moniliform striae^ the beads of which are so spared as to give a 

 marked wavy appearance to the valve; raphe olisourely beaded, especially toward the 

 center, there each half slightly Ix^nt toward the same side of the valve; a broad 

 median area on either side tln^ raping extended at the center as a large stauros run- 

 ning from one side of the valve to the other; ternunations of the raphe at the extreme 

 apices of the valve surrounded by large hyaline circular areas^ reaching over the 

 curve of the apices to the l)order. 



Length of valve, 0.080 mm; wi<bh of valve, 0.019 mm. Striae, 17 in 0.01 mm. 



This very minute but robust diatom belongs to the A^. aspera group, (\xcept for its 

 coarse beads being round and iLs central hyalini' band extending from one side to the 

 other, like the stauros of the Stauroneis typ(\ It is iji juarked contrast with any 

 known iurm, the nearest s])ecies bt'ing N. viavraeava Pant.,^ which differs greatly 

 in. its apices, its delicate Ix^ading, its stauros, its rajthe, et,c. 



Tyi)e in the \\ S. National Museum, No. r)IK)b52, from station :i57HI, Ih'ring Sea, 

 July G, 1895; i'AH) fathoms, bottom of grt^Mi mud and ooze. 



Navicula vagabunda Ib'un; Scluuidt, Alhus pj. 174. f. ■^- l^^^-. 



Diploneifi nujahunda Cleve, Sv\ Nvi. AkaH. riarull. 26': lO:]. pL -*./ ij, 75. 18*M. 



This diatom is suggestively near tliat variety of X, i-rabro ( Khrenb.) Kiilz., known 

 as N, pandnra Brcb. 



Found at slalicm 2808, Galapagos Islands. 



Navicula vidovichii Grun. Verb. ZiH.h ISot. Ges. Wuui 13: 150. pi. 1A, f. 4. hS(>:^. 



Plate Id I, teouuk 3. 

 Navicula egy plica Grev. Trans. !Micr. Soc. bond. n. s. 14: 127. jd- ^^-f- Ki-H. 188(). 



Moel^' Diat-taf. pi. 75. f. lil-17. ISOO. 

 Navicula bartholovjei Cleve; Schmidt, Atlas pi, 160, /. l). 181)0, not Cleve, J5ih. Sv, 



Vet. Akad. Ilandl. 5'^: 6. /)/. /. / 5. 1878. 

 Narioda scdilis Schnudt; Taut. lU^tr. IJacill. Ung. 2: 55. pi S,f. 152, 1889?. 



Th(^ above combination represents a clear and satisfactory specific concept. N. 

 eyypfira is exactly the same as N. ridovivhil; the variety called by Schmidt A^ 

 bartholoviei Cleve variety, differs merely in Ixung more constricted at the center of 

 the valve, and the variety calh^d l)y Pantocsek A^. sectiHs boryana differs merely 

 in being less constricted at the center of th(^ valve. To add to these^ther species less 

 ch^arly related^ though similar, as Cleve/ and De Toni g have done, is to lose all boun- 



ty Donk. Brit. Diat. pi 7. f. 8b. 1871-73. 



^ Bih. Sv. Vet. Akad. Ilaudl. S'""^: pi L /, 4. 1876. 



c Denkschr. Akaib \Vi*Mi 48'-: 50. 1884. 



^Proc. Roy. Irish Akad. 11. 2: 398. pi SS,f. 22. IS 

 ePant. lieitr. Bacill. Ung. 2: 52. plS.f.l55. 1889. 

 /Sv. Vet. Akad. Ilandl. 26-: 03. 1891. 

 £?De Toni, Syll. Alg. 2: 174. 1891. 



