!_. ' 



MAINX — DIATOMS OF THE ALBATROSS VOYAGES, 269 



incidentally on the anastomosing of the shadow lines near it? renter, we certainly 

 recoirnize a difference as wniall as is conrii^tcnt with any di;stinrliun at all. Tliere is 

 excnpc for this in the fact that all nieml)ers of this genus uro cluboly allied aud tlilTer- 

 encc-s may be recognized to divide up the large juiinber of its forms which elsewhere 

 would hardly serve that purpose. Rut having made this admission, there is nothing 

 left on which to base a distinction between Greville's S. johnsonianns and Ui(»se 

 quoted above as synonyms. Tnaratium jercmiannm is simply a polygonal instead 

 of a circular specimen of the same diatom,^ and thi^^ divergence, l^eing a mo?t common 

 one in the genus, counts for nothing. Su 5. caraibicus has a few more beady than the 

 triangidar examples of S. johmonianus on the same plal e. The ''spiral arrangement " 

 of the beads in S. tniani, its only distinction, is dilhcult to detect and of no worth 

 when detected. The figure of S. radiatus is almost as fine a copy of Greville's original 

 figure of S. johnsonianns as couhl b(^ asked for. Other forms might be added to the 

 al)ove list, as their differences arc uf somewhat questionable weight; as S. piiMdlus 

 Truan & Witt,& S. grunowii Truan & Witt.c S. affinis Castr.,^ S, trigontis Castr./ 

 S, margaritaceus Castr./ A liltle further removed, solely by the character of the 

 border, is S. califomicus Grev., together with a number of its synonyms. £7 



1 have united a large number of circular and triangular specimens under this species, 

 mounted specimens of which accompany this report. 



Found at stations 2807, 2808, 292011, 3008H, 3G(11, 402!):il, Galapagos Islands, Hawai- 

 ian Islands. 



Stictodiscus kittonianus Grev. Trans. Micr. Soc. Lond. n. s. 9; 77. pllO.f.2-3, 

 180t. Moeb. Diat.-taf. pi ^/. 2-S. Schmidt, Atlas p/. 74./ ^^-AS\ 18S2. Dc Toni, 



Syll. Alg. 2: 13b5. 1894. 

 This delicate form, not infretiueut in the fossil deposits of Maryland and Virginia, 



has been found on the Pacific slope nnly in the fossil beds of Monterey, (\difnniia. 



The specimen discovered by me came from Bering Sea. north of the Aleutian Islands. 

 Found at station 402911, Bering Sea. 



ACTINOPTYCHXJS Ehrenb. 



Adinoptychus Ehrcnl). I'liys. Ahli. Akad. Wiss. Bvr\. 1841: 400, 409. pi L I.f. 27. 



III. 22. 1843; Am. Jouru. Sci. 46: 300. 1844. 



/■ 



Omphalopelta EhronV). Ber. Akad. Wiss. Beii. 1844: 270. 1845, in part. Tastr. Krp. 



Voy. Chall. Bot. 2: 120. pL 7. f. 2, 131. pi. IS. J. 0. 1880, in toto. 

 ITeliopeUa. EhrenL. Mikrog. pi 33. XVIIl. f. 3. 1854. Joliiist. Quart. Journ. 



MitT. Sci. 8: 13, 18. ISfiO. Rails in Pritch. ITi.^t. Infu.s. ed. 4. 840. ISHl. 

 IIulionyxi'Mranh. Mikrog. pi. 35 A. XXI. J. 12. 1854. .Tan. Abli. Sclil. Gfs. Vut<Tl. 



Cult. 1861': pi. I.f. 1. 18(11; 1862- : pi la. f. G. 1802. 

 Adinnphacnia Rhadl). Traii.s. Micr. Sue. Lond. n. s. 16. 1854; Quart. Journ. Mlcr. 



Si-i. 8: 94. plG.f. 18. ISOO. 

 Schudtia Dv Ton!,, Sjll. .\lg. 2: 1395-9G. 1894. 



Closely alli^'d to the above geiuiw are Debya Pant., Anlhudiscus Gr. & St., Lepido- 

 discus Witt, Actinodietyon Pant., Wittia Pant. They fall into 11. L, Smith's iamily 



a Of. Truan ct Witt, Dial. Ilayti pi 6.f. 9. 1888. 



ft Truan & Witt, Dial. Ilayli 20. pi G.f. r,. 1S88. 



cOp. cit. pi ■',./. 25, pi 5. J. .S', pi G.J. 31. 



d Castr. Be]). Voy. Chall. Bot. 2: 119. pi I.f.',. 1886. 



«0p. cit. 122. pi 31. f. 1. 



/Op. cit. 120. pi 17. f. 12. 



gTran^. Micr, Soc. Lond. n. s. 9; 79. pi Hi. J. 1. ISCl. 



