Bacillariete, Naviculacese, Stauroneis. 215 



versus constrictis, apicibus late rotundatis, stauro rhombeo valva- 

 rum margines attingente; striis transversis validis, remotis. 4-5 

 in 10 a., valde arcuatis, inter binas lineas subtilissimis. 



Tlab. inter algas confervaceas Germania?, passim (L. Ra- 

 benhorst). 



53. Stauroneis rhombica 0'Meara in Q. J. M. S. 1867. p. 246, t. 7, 919 

 f. 3. — Valvis 40-42 = 30, rhomboideo-ellipticis, apicibus anguste 

 lanceolatis; striis subtilissimis, punctatis, parallelis, stauro angu- 

 sto, ubique aequilato, dimidiam valvae latitudinem longo, ergo a 

 marginibus remoto; rhaphe valida. 



Hab. ad insulas Arranienses (0'Meara). 



54. Stauroneis apiculata Grev. in Edinb. New Ph. Journ. vol. X, 920 

 p. 30, t. 4, f. 8. — Valvis elliptico-ovatis, 50*25, obtuse apicu- 

 latis, stauro lineari, fere 10 u. longo, margines ergo non attin- 

 gente; striis transversis subtilibus, 12-13 in 10 u. 



Hab. in Guano Californise. 



55. Stauroneis costata 0'M. in Q. J. M. S. 1867, P . 246, t. 7, f. 4. 921 

 — Valvis ex elliptico lanceolatis, 50-52 » 21-23, apicibus rotunda- 



tis ; striis distincte costatis, eleganter undulatis, stauro rectangu- 

 lari, dimidiam valvae latitudinem longo, ergo a marginibus remoto. 

 Ilab. ad insulas Arranienses (O' Meara). 



56. Stauroneis finmarchica Cleve et Grun. Arct. Diat. pag. 47, t. 3, 922 

 f. 63. — Valvis lanceolatis, 30-42*11,5-13, apicibus paullo pro- 

 ductis rotundatis; spatio levi prope rhaphen angusto; nodulo cen- 

 trali transverse dilatato, dimidiam valva?. latitudinem haud omnino 

 occupante, striolis longitudinalibus 4 brevibus (ceteris validioribus) 

 limitato ; striis transversis subradiantibus, 12-14 in 10 u.., levibus, 

 utrinque linea levi ante apices desinente interruptis. 



Hab. ad oras Finmarchise, haud raro (Cleve, Grunow). 



57. Stauroneis Bacillum Grun. in Wien. Verh. 1863, p. 155, t. XIII, m? 

 f. 16. — Minor, valvis anguste lineari-oblongis, 25-36*5-8, api- 

 cibus rotundatis ; nodulo centrali magno, utrinque in staurum ma- 

 gnum, valvarum margines attingentem producto ; striis transver- 



sis tenuissimis, ultra 24 in 10 a. 



Hab. in aqua subsalsa ad littora Anglise prope « Newhaven » 

 (Grunow). 



58. Stauroneis Wittrockii Lagerst. Diat. Spetsb. p. 38, t. 2, fig. 15, 924 

 Hedwigia 1874, p. 119. — Frustulis e facie connectivali visis re- 

 ctangularibus; valvis linearibus, medio leviter dilatatis, apicibus ro- 

 tundatis, 23-26*6-9; nodulo centrali breviter transverse dilatato, 



