MANN- -DIATOMS OF THE ALBATBOS6 VOYA< 323 



this and II. robustum Grun., l>ui have doI succeeded. So tar as the valval view is 

 concerned, neither the median line, the arrangemenl and punctation of the striae, 

 the outline, the Bize, the character of the border, or the shape of the apical hyaline 

 areas give any constant marks of distinction. So Ear .1- I am aware, robustum never 

 displays the striking double-lobed valves commonly met with in japonicum; but 

 unfortunately this feature 1- not at all constant in the latter, and in fact the original 

 type 1- not of that Bhape. a The only appreciable difference is to I"- found in the 

 zonal view. The striae in japonicum are generally small and narrow, forming a closely 

 set row for each compartment of the Beries made up of coarse but obscure blotches, 

 giving a semimoniliform appearance to the striae; or if the striae be broad and the 

 blotches approach Bquares, they are also coarsely dotted. Robustum has generally 

 large square markings, Bet loosely in the rows of each compartment, and marked with 

 fine puncta. I am convinced that these two Bpeciee are with difficulty to be kepi 

 separate; and that a study of the abundant figures in Schmidt & will prove this. 1 

 have named my specimens solely on the basis of the zonal markings, and many 

 valves unquestionably belonging to a Bingle Bpecies, but no1 affording a zonal view, 

 could with equal accuracy be given Grunow's specific name. 



The variety called by Pantocsek /.'. mikado occurs at station 3688H. 



Found at stations lMI. i'Mv :;<;oi. :',()88H, 3784, Bering and < >khot« 



ENTOPYLA Ehrenb. 



)pyla Ehrenb. Ber. Akad. Wiss. Berl. 1848: 6. L849. Grun. Verh. Z I B t. 



3. Wien 12: 428. L862. Schmidt. Atlas pi 2S1. 1902. De Toni, Syll. Alg. 2: 



773. L892. Pritch. Eist. Infus. ed. 4. 810. 1861. Rabh. PI. Eur. Alg. 1: 308. L864. 



EupU uria Arn. Quart. Journ. Micr. Sci. 6: 89. 1858. Pritch. Bist. Infus. ed. 4. 809. 



1861. 

 Margaritoxicon Jan. Abh. Schl. G«s^l862 2 : 6. L862, as Bynonym. 

 Gephyria Arn. in part; Quart. Journ. Micr. Sci. 8: 20. 1860. Pritch. Hi-'. Infus. 



ed. 4. 809. pi. .. f. 50. 1861. 

 Achnanthes Bory, in pari: Johnst. Quart. Journ. Micr. Sci. 8: L5. pi. 1.1 



- Irella Turp. in part; Ehrenb. Phys. Abh. Akad. Wiss. Berl. 1841: 388. pi. 1. f. 

 f. 96. L843. 



The distinctive marks separating this genus from Gephyria Arn. arc summarized 

 by Schmidt/ as follow-: 1 The costae on the valves of Entopyla alternate on either 

 side the median line; in Gephyria they arc transversely continuous. 2 The inter- 

 nal Bepta in Entopyla have their pores in a longitudinal straight row along either 

 side and therefore -how as Btraight row- of dots through the costae; in Gephyria 

 these pores arc in two zigzag longitudinal Beries. 3 These pores arc in Entopyla 

 close to the margin on either Bide; in Gephyria midway between the margin and 

 the median line. Although the foregoing characteristics arc well marked and Beem 

 to be constant, they constitute at best a -canty basis for generic distinction between 

 form- otherwise bo much alike. 



Entopyla australis Ehrenb. Ber. Akad. Wiss. Berl. 1848: 6. 1849. Pritch. Bist. 

 Enfus. ed. 1.810.1861. Jan. Abh. Schles. Ges. Vaterl. Cult. 1862. 2. pi 



U; . L862. De Toni. Syll. Alg. 2: 773. L892. Schmidt. Atlas pi. 



!',. L902. 



- irella australis Ehrenb. Phys. Abh. Akad. Wien 1841: 388. pi ! If. ■■ . L843. 

 Pritch. Eist. Infu-. ed. I. 798. L861. 



Eupleuria incurvata Arnott, Quart. Journ. Micr. Sci. 6: 90. 1858. 



a <f. Schmidt, Atlas pi : 



'•<>].. cit. pi. 'A. 



<<>].. cit. pi .'■■!. L902. 



