MANX DIATOMS OF THE ILBATROSS VOYAGES. J.) I 



the cells ii"i small, bul with very delicate wall-, marly uniform in size until within 

 one-fifth of the radius from the margin, then rapidly decreasing i" the margin; no 

 dot.- or puncta within the hexagons; Lnterradial Lines Erequenl toward the margin; 

 border a thin hyaline band; outline uniformly irregular bydepn »ne side. 



Diameter of valve from 0.138X0.109 mm. to 0.080> 0.07] nun. 



Type in the U.S. National Museum, No. 590120, from station 2£ 

 [glands, April I. L888; 812 fathoms, bottom of Globigerina ooze and coral mud: col- 

 lected also at station 3013H, Hawaiian Lslands. 



This form is aol to be confused with the irregular, generally subtriangular exam- 

 ples of C. heteroporus Ehrenb., classed as C. <'>< ■ '.run." The far 

 greater delicacy of the network, the absence of papillae, and the uniformity in the 

 hexagons over the greater part of the valve, clearly distinguishing them. It i- 

 abundanl at both the above stations, the firsl of which is close to the ( ralapagos Lslands 

 ami the second close to the Hawaiian Lslands. This unusual form must therefore 

 be looked upon as a subtropical littoral species. 



Coscinodiscus denarius Schmidt, Atlas pl.57.f. 19-22. l v 7v Ratt. Proc. Roy. 

 Soc. Edinb. 16: 504. L889. De Toni, Syll. Alg. 2: L238. 

 Coscinodiscus variolatus Castr. Rep. Voy. < hall . Bot. 2: L55. pi. :.j. 5. - 

 It is doubtful if this has sufficienl specific difference from C. symi ■ 

 warrant the above name. It is certainly uol sufficiently different from the : - 

 so named by Schmidt. & Compare also Greville's original figure. « 

 Pound at station 3097, off central California. 



Coscinodiscus elegans Grev. Trans. Micr. Soc. Lond. n. s. 14: :'». pi. l.f. 6. - 

 Schmidt. Atlas pl.S8.f. 7, pi t6S.f. 10. L878. Pant. Beitr. Bacill. Ung. 1: 

 pi. 16. f. 141 (?), pi U.f. 216. L886. Jan. Diat. Gaz. Exped. pi \. . ■ . Cleve 

 & Moll, type no. 164. Truan ct Witt, Diat. Hayti L4. pi .'./. :/. L888. Ratt. 

 Proc. Roy. Soc. Edinb. 16: 585. 1889. DeToni, Syll. Alg. 2: L293. L894. M 

 Diat.-taf. pi 70. f. 6. 1890. 

 Coscinodiscus margaritaceus Castr. Rep. Voy. ('hall. Bot. 2: 164. pi 18. f. S. L8E 

 Of the above figures the firsl of Pantocsek's is worthless; those in Janisch and in 

 Luard & Witt must be looked upon as representing extreme varieties. 



fn the specimen accompanying this report the trust uh- has two valves quite differ- 

 ent in the arrangement of the beading, a good commentary on the constantly repeated 

 absurdity of making "new species" out of Buch trifles. 

 Found at station 3(i04H, Bering Sea. 



Coscinodiscus excentricus Ehrenb. Phys. A.bh. Akad. Wiss. Berl. 1839: L46. 

 1841: 1841: 323. pi 8. VII. f. 5. L843; Mikrog. pi :. pi 11. f. 6. 



W.Smith, Synop. Brit. Diat. 1: 23. pi 8. f. 88. L853. Schmidt . Atlas pi 

 f. 46-49; Jahresb. Komm. Deut. Meere 2: pl.S.f. 86-88. L874. Grun. Denkschr. 

 Akad. Wien 48-': 84. pi ,I>. f. 7. L884. Van Beur. Synop. 217. pi 

 :. 8. L881. Jan. Diat. Gaz. Exped. pi. :.j. 8, pi 6. f. 8, 7-11. 11. I.. Smith, 

 Sp. Diat. Typ. no. 93. L874. Van Beur. Typ. Diat. Belg. qo. 529, 530. Cleve 

 & Moll, typ.- no. L48, L50, L83, 207, 210, 211, 215, 228, 257, 258 276. Ratt. P 

 Roy. So,-. Edinb. 16: 161. L889. De Toni, Syll. AJg. 2: L210. L894. 

 Odontodiscus excentricus Ehrenb. Ber Akad. Wiss. Berl. 1845: 79. L846. Schmidt, 



JahreeD. Komm. Deut. Meere 2: 94. L874. 

 Eupodiscus excentricus O'Meara, Quart.* Journ. Micr. Sci. 7: 245. pi :./. :. 1867. 

 Moeb. Diat. -tat. pi 77. f. '. . L890. 

 icinodiseus minor Schmidt. A.tlas pi 118./. 9. L888. 



« Schmidt. Atlas pi 61. f. 7. L878. 



&Op. ,ii. v l 57. f. .'■; 



< Trans. Micr. Soc. bond. n. s. 9: 68. pl.8.f. . 1861. 



