270 • CONTRIBUTIOXS FRO:\I THE NATIOXAL HERBARIUM. 



grouping IlL-li(>prl(('U(%^' in whicli is also inrhided rolymyxus T5ail.j agonus which I 

 think lias closer alTinily witli Aulivcixlisrus (Ehrenl>.) T^atl. 



The original union of Arlin<)]>( yrhus and Artinocydus l)y Ehrcnlxn-f^ and (lu? sub- 

 sequent Ropanition of the former hy I he erealion of lliul gc^nus in 1839 ha.s been dis- 

 cussed under Aetin(jcyehLs. I( luay be well to quote h^Te the uriirinal Eln^eidK^rg 

 distinction betwe^^n Ihe two as if is giv<ni by T. W. liaili^y.^ ''Under llu^ \w\y genus 

 Aetinoptyehus are now jjlaced thos<' speeiet? of the old gentle Aelinocyelus which pos- 

 sess internal parlilions or folds, while under the old name are retained those in which 

 the external rays are not connected witli intt^nal folds." 



Aetinoptyehus alternans Mann, sj). nov. Plate XT.V, Fuarn?: 1. 



Valves circular; divided into HI alternating .sc^gments, S of which bear each a 

 minute rounded ]>rocess close to Ihe margin, its l)ase not surrounded l^y a hyaline 

 area; these segnu^nts evenly marked with minute rows of beads, parallel to tin* cen- 

 tral row or rows: tliat is, not radially arranged; luimlxa'of rows per segmf^nt, 11 <ir 15; 

 the 8 segnu'iits alternating willi these \vithont processes, marked with mu'h 

 largei- beads n^gularly placed in <liag<mal ]»arall(^l rows; iiuier ends of these segmeius 

 proceeding slightly farther toward llie ct^nler Hum thos(^ bearing processes, and lu^nce 

 giving a Rt(01at(^ app(\u^ance to the h\'aline median an^a; the (external (>nds of lluvsci 

 segments showing a narrow hyaline l»an<l next to th(^ rim: rim narrow, hyaline. 



Diameter of valve, O.0357 to 0.0 loO mm. 



The gc^iuTal asp(H't issimilarto minute forms of A. riiJfians Schmidt and io .b hicvi- 

 yafiis Gnin., forma parva.<^ It is also apparently lik<^ th(^ rather obscure unnamed 

 figure f^ whicli (irovt^ I'igbtly c(msi(hM's to be different fnun A, degans Ilalfs. 



Typo in tlie \\ S. National Museum, No. o90125, from station -151GII, Gulf of (^ali- 

 fornia, Dec(^ml)er 22, 1904; 1,027 fathoms, boil om ol* volcanic sand, obsidian, and 

 fragments of Gh)bigerina. 



Al:so a variety of Ihe above, in whic^h the segments bearing processes are underlain 

 with secondary markings of coarse. be:ul-lik<' dni^ irregularly disposed. 



Found at stations 2(;90II, l)etween t\dilornia and the Hawaiian Islands, and i:)Hd[ 



in the South Pa<Hric. 



Aetinoptyehus grundleri Sehmidt, Atlas pL /./ 22. 1875; /)/. 90,/. 7, pi 100. J. S-4, 

 1S8G. rant lieitr. Bacill. Ting, 1: pi. 12. J. lOG. 18S7. 



My specimen differs from the type in that the hyalin*^ si)aces between the outer 

 extremities of the segments are not tuiited l>y thin liyaline bands parallel to tlie margin. 

 Found at station 2835, off Lower California. 



Actinoptychiis janiBchii Grun.; Van Wmr. Synop. pi 122. J. G. 18S1. Schmidt, Atlas 

 pJ, 153. f. 8-10. 21. 1800, Pant. Ih-itr. Baeill. Vug. 1: pi ifL f. 14.L 1887. De 

 Toni, Syll. Alg. 2: K]88. 1894. 

 TTaHonij.r rJcenan'iL^ Jan. Abb. Seldes (ies. Vat(^rl. Tult. 1862-: 10, pi L f. 2. 1802. 



The above speci fie iianuM)f Janis<-h, tlunigh older than A. jatusrhu, was jirec^mpttHt 

 by ActitioptijcJiUS rivenarius I'^ln-eid).,^ a decidedly diflVrciU <!iatom, willmut i)rocH'sseR 

 and having no liyaline lines bisecting the S(^gm(>nts. 



Found at station 282:^. 



« The Lens 1: S, 17. 1872. 



ft Am. Journ. Scb 46: 300. 1S44. 



^^(hmidt, Atlas pi, Lj2,f. l'>. 1800. 



f^ Schmidt, Atlas, pi 153. f. -j. 1800. 



^rhys. Abb. Akad. Miss. BerL 1841:410. 184:^ Khrenl). Mikrog. pi 18. J. 28. 



1854. 



