474 
Proceedings of Royal Society of Edinburgh. [sess. 
C. marginato-lineatus. Sch., Atl., pi. lix. fig. 33. — Diam. *0335 
mm. Central space absent. Markings hexagonal, equal 3J to 4 
in *01 mm. Border about \ of radius broad; strise distinct, 6 to 8 
in *01 mm., the inner half separated from the outer by a distinct 
narrow line. 
Distinguished by the regularity of the markings and border. 
Habitat. — Campeachy Bank (Schmidt). 
C. peruanus , Grun. Sch., Atl., pi. lviii. fig. 43. — Diam. *0425 
mm. Central space absent. Markings polygonal, decreasing 
slightly from the centre outwards ; towards the centre 5, towards 
the border 6 in '01 mm.; the oblique decussating rows straight or 
slightly curved outwards, well-marked ; apiculi numerous, distinct, 
close to the border. Border hyaline. — Grun., Denk. Wien. Ah., 
1884, p. 85. 
Distinguished from C. excentricus by the size of the markings, 
the apiculi, and border. 
Habitat. — Peru guano (Schmidt). 
C. sublineatus. C. {excentricus, var. 1 ?) snblineatus, Grun., Denk. 
Wien. Ak., 1884, p. 85, pi. iv. (D), figs. 21, 22.— Diam. -032 to 
*053 mm. Central space and rosette absent. Markings hexagonal, 
gradually decreasing towards the border ; at the centre 5, at the 
border 9 in ‘01 mm.; the oblique slightly bent, decussating rows 
distinct, non-apiculate. Border narrow, hyaline. 
Distinguished from C. excentricus by having the markings at the 
border smaller in proportion to the others, and from C. lineatus by 
the less uniform markings. 
Habitat. — Pranz Josef’s Land, White Sea (Grunow) ; Simbirsk 
Polirschiefer (Grunow). 
C. august e -lineatus. Sch., Atl., pi. lix. fig. 34. — Diam. *0275 to 
•0455 mm. Central space and rosette absent. Markings polygonal, 
subequal, 6 in *01 mm. Apiculi minute, sometimes indistinct, at 
the border. Border narrow, hyaline. — Janisch, Gazelle Exped., taf. 
iii. fig. 6. C. lineatus, var. tenera, Tru. & Witt., Jeremie Diat., 
p. 14, pi. ii. fig. 2 ; Cleve and Moll., Diat., No. 154. 
Truan and Witt’s C. lineatus, var. tenera, differs chiefly, according 
to the figure in the somewhat more distinct appearance of fasciculi 
