372 Transactions of the Society. 



ends of compartments scale-like, their edges flexuous. Primary rays 

 distinct from inner edge of elevated zone, space between rows wide, 

 diminishing towards processes. Border striae 8 in 0' 01 mm., 1/35 to 

 1/55 of radius broad, inner edge undulate, formed by rounded outer- 

 most meshes of reticulum. Processes 5 to 10, insertion 1/5 to 1/8 of 

 radius from circumference, narrow, constriction median, shallow, wide, 

 free ends rounded, a curved line close to base sometimes distinct, 

 length 2\ times breadth.— Pant., Fossil. Bacil. Ung., p. 58, pi. xi. 

 figs. 93, 95 ; Sch. Atl., pi. cvii. figs. 1, 2. A. hinherianus E. S. 

 Nott, Walker & Chase, New and Bare Diats., p. 3, pi. i. fig. 9. 



Habitat : Briinn Tegel (Cleve ! Weissflog !) ; Kekko, Szent Peter 

 and Szakal deposits (Pantocsek !). 



Var. subsquamosa Pant., ibid., p. 58, pi. i. fig. 3 ; pi. xii. 

 fig. 100. — Diarn. 0'16 to # 27 mm. Surface flat to processes, 

 with edges concave between these, slope to border less steep. 

 Colour pale grey, darker towards border. Central space round or 

 angular, 1/22 to 1/28 of diam. broad. Markings in rows slightly 

 deflected at processes ; reticulum indistinct, disappearing towards 

 outer edge of raised area, at border again indistinct. Primary rays 

 undifferentiated on inner half, rarely traceable to central space, space 

 between rows narrow. Processes 9 or 10, insertion 1/6 to 1/7 of 

 radius from circumference. — Sch. Atl., pi. xcii. fig. 1 ; A. Orunowii 

 f. punctata Pant., ibid., p. 59, pi. xii. fig. 102. 



Habitat : Szent Peter, Szakal and Kekko deposits (Pantocsek !). 

 Yar. squamosa Pant., ibid., p. 59, pi. i. fig. 4. — Diam. • 1 1 to 

 0'115 mm. Surface with slope to border gradual. Central space 

 1/16 to 1/22 of diam. broad, hyaline or punctate. Markings round, 

 oval, interspaces irregular, rarely polygonal throughout, outlines 

 prominent ; reticulum with polygonal irregular meshes more manifest, 

 a single band at periphery with smaller meshes than in var. sub- 

 squamosa. Primary rays distinct to central space, rows often inter- 

 rupted. Processes 6 to 9, insertion 1/3 to 2/9 of radius from 

 circumference. 



Habitat : Briinn Tegel (Cleve !) ; Szent Peter and Szakal 

 deposits (Pantocsek !). 



A. Rogersii Sch., Atl., pi. cvii. fig. 3. — Diam. 0-095 to 

 0*22 mm. Surface flat for about 2/5 of radius, thence rising 

 gradually to highest zone just within processes, this zone convex, 1/4 

 to 1/5 of radius broad, its inner edge circular, indistinct, its outer 

 more manifest, angular at processes, slope to border steep. Colour 

 pale grey, darker towards border. Central space indistinct, angular, 

 1/25 to 1/32 of diam. broad, reticulate. Markings granular, irregu- 

 larly round, interspaces wider towards centre, rows inconspicuous 

 within, moniliform outside of processes ; reticulum absent from 

 highest zone, elsewhere distinct, around border two concentric bands of 

 meshes more prominent, those on the outer larger and more distinct, 

 within highest zone an indistinct concentric arrangement of meshes 

 recognizable to centre. Primary rays inconspicuous, rarely evident 



