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MANX DTATOMS OF THE ALBATROSS VOYAGES. 271 



Actinoptychus mOlleri Grun.; Schmidt, Atlas ;?;. JS2.f. S-9. 1888; pi 154-f- 5. 1890. 



In our specimens the contra! arc^a is formed into a f^trong hyaline star l)y the exten- 

 sion of tlie ends of the imdulatin^^ peginent?. 



Fouiul at stati(jn 2807, Galapagos Islands. 



Actinoptychus planus Mann, sp. nov. Plate XLV, figure 2. 



Valv(\s circular, divided into .six segments of equal ^^i/.e and identical markings, 

 th(M"r surfaces lying nearly in <)n<^ ])huie; tliree heaiing each a minut(^ globular proc- 

 ess, set on the extreme outer margin of the valve, the alternating three showing obscure 

 ru(Iii]ionts of such proc{^ss<^s; markings of minute l>eading <'h)sely placcnl, not in per- 

 fect rows, but so arranged as to give a faintly l>h)tched or wavy app(^arance to the 

 surface; no hyaline bands at the oulor margins itf the st^gments, but their outer cor- 

 ners s<'pai*ated by small triangular liyalinc areius, the (extremities of the six lines of 

 divisioji; central area unusually small, cinular, liyaline; rim a nn^n' line, apparently 



smoo 



th. 



Dianu^ter of valve, 0.0525 mm. 



Type in the U. S. National Museum, No. 59012(1, from staticm 4021)11, Bering Sea, 

 Juno 27, 1900; 913 fathoms, bottom of gray sand nnd clay. 



Actinoptychus punctulatus Pant. FUitr. Bacill. T"ng. 1: G2. pL S. f. GO, 1887. Do 

 Toni, NotarisiaS: COS. 1888; Syll. Alg. 2: 1.S74. 1891. 

 Actinoptychus int erw edius Schmidt, Alias pi. 91. f. S (not/. 2), pi, 109. f. 12. 1886. 



As is pointed out l)y De Toni^^ Schmidt has inc luded under his name iniermedius 

 two quite distinct forms. That represented by figure 2 in ])latc 91 should be taken 

 as type; the other (fig. 3), agreeing wilh Pantocsek's species, should be placed henj. 



Found at stations 2S07, Galapagos Islands, and 2920II and 301311, between Cali- 

 fornia and Hawaii. 



Actinoptychus radulus ^ilanUj sj). nov. Plate XLV, figure 3. 



Valve circular; dividend into G equal segments, each bearing a stout, rounded proc- 

 ess, arising close to the rim and ]jrotrudiug slightly beyond it, its base surrounded by 

 a small oval or cuneiform, hyaline spac<^ which narrows inward to a thin line runniiig 

 to tlu^ center of th(^ valve, thus bisecting the s(?gm(nit; markings of minute beads 



regularly arranged in diagonal cross lines; each segTn(?nt slightly wider at the outer 



margin than its length radially, thereby leaving an uunsually large liyaline central 

 area; rim narrow, finely crossed with lint^s and blearing bhmt, stout teeth closely set, 

 giving to the outer edge a serrate appearance; the segments alternatdy sUghtly con- 

 cave and convex, as in many other sptn-ies. 



Diameter of valve, 0,078 mm. 



Type in theU. S. National Mustaun, No. 590127, from station 292011, between Cali- 

 fornia and Hawaii, November 21, 1891; 570 fathoms, bottom of brown nuid and fine 

 saD{l. 



Actinoptychus splendens i^Shadb.) Ralfs in Prit(^h. Hist. Infus. ed. 4. 810. 1861. Van 

 Heur. Synop. pi 119. f. 1^2, 4. 1881. Pant. Beitr. Pacill. Ung. 1: 03. pL 16. 





/. /^O. 1887. DeToni,Sylh Aig. 2: 1385. 1S94. S(Onnidt, Atlas/)?. I5SJ.S, lS-1 

 Ad 11 top] taenia splnidcns Shadb.^ in bright. Quart. Journ. Micr, Sci. 8: 94. pi 6,f, 18. 



18G0. Moeb. Hial.-taf. pi 20 J. IS. 1800. 

 Ilallonyx undenarliis Ehreub. and //. Ini^cnar'uLs Ehronb. Abh. Rchles. Ges. VaterL 



Cuh. 1861^: pi l.J\ /. ISGl; 1862-: pi 7.1./ C. 1802. 



^^Sylh Alg. 2: 1374. 1894. 



^This name Avas originally puldislunl by ShadlM)lt in Trans. Micr. Soc. Lond. n. s, 

 2: IG. 1854. The descrii)tion is insuflicient for a d(^termination, but Brightweirs 

 identification may be correct, inasmudi as he was a contemporary worker and may 

 have seen authentic material. 



