58 



MARINE AND FT S EERIE 



6-7 EDWARD VII., A. 1907 



49. Nitzschia vermicularis (Kg.) Grun., 165 x (9 :12 : 9 to 175 x 13 to 210 x 

 (7.5 :9.5 :7.5). Pearls about 7. 



50. Nitzschia lanoeolata W. S., 140 x 12. Pearls about 6 to 10 microns. One 

 specimen in Zostera collection. 



51. Nitzschia plana W. S., 150 x 17. Striae (coarse and fine) 7 and 18. One 

 specimen noted. 



52. Nitzschia Sigma W. S. Var. intercedens Grun., 280 x 8 to 295 x 15. Striae 

 about 6. Not uncommon. 



53. Nitzschia Closterium W. S., 120 x 6. Not strongly silicified. 



54. Nitschia paradoxa Grun., 100 x 5. An interesting plankton species. 



55. Surirella Gemma Ehr., 108 x 50. Gestae 2 or 3 to 10 microns. One specimen. 



56. Campy lodiscus decorus Breb. One specimen. 



57. Campylodiscus (?). Suborbicular, 50 microns in diameter. Mar- 

 ginal costae against larger and smaller parts of circumference about 2 or 2.5 to 10 

 microns. Subcentral area 50 x 22 with striae running from ends of oostse 

 into a slightly curved and eccentric diameter line ; 10 striae to 10 microns. Approaches 

 C, Thuretii Breb. and C. Bamoensis Grun. Van Heurck's description of 0. Thuretii 

 applies exactly to the specimen, although the figure given in the Atlas shows some- 

 thing like three pseudoraphes instead of the one referred to above as the curved ex- 

 centric diameter. 



57. Chaetooeros Janischianum (?). A plankton form of which one specimen was 

 observed in a mount from one of the collections. 



58. Melosira distans Ag. Diameters 9 to 14. Length of joints 5 to 7. 



59. Melosira sulcata Kg. (?). 



60. Melosira sculpta Ehr., 21 to 24 in diameter. Joints or frustules 5 to 6. 



61. Melosira granulata (Ehr.) Ealfs. 18 to 22 in diameter, 48 points around cir- 

 curference of frustule. Erustule 18 x 6. Rows of granules 9 in 10 microns. 



62. Melosira nummuloides Ag. Diameter 12 to 27 microns. Quite abundant in 

 the N. corymbosa material. Very faint, irregular and defective longitudinal wavy 

 striations, closer than one micron when not defective, just visible on the frustules. 



63. Biddulphia aurita (Lyngb) Breb. (12 + 15 + 10) x 16.5, (12 + 18 + 12) 

 X 24, (12 + 14 + 11) X 27, (10 + 12 + 11) x 30. Bows of points about 10 in 10 

 microns, and uniform over middle segment and end segments. The type of this 

 species in Moller's Typen-Platte, has larger granules or points on the domed end seg- 

 ments. 



I 64. Biddulphia Boperiana Grev. (14 + 28 + 12) x 37 to (18 + 23 + 13) x 62* 

 Rows of points about 7 to 8 on cylinder, more crowded on domes. These two last 

 species are not uncommon ; and they look so much alike that it is a question if they 

 should not be considered two varieties of the same species. 



65. Triceratium (?). Specimen 12 microns in diameter. 



66. Auliscus ( ?) One specimen seen but lost. 



67. Actinoptychus undulatus Ehr. (?). 



68. Actinocyclus (?). Diameter 45 microns. 



69. Hyalodiscus subtilis. Bailey. Diameter 24 to 27. Dark center 8 to 10. 



69. Cyclotella operculata Kg. (?). Diameter 12 microns. 



70. Coscinodiscus radiatus Ehr. Rare. 



71. C. robusta Grev. Fragment. Each alveolus 3 microns in diameter. 



72. 0. excentricus Grun. ( ?) . Diameter 25 microns. 



73. 0. concavus Ehr. (?) 45 microns in diameter. 



