KOXGL. SV. VET. AKADEMIEXS HAKDLIXGAR. BANT). 18. N:n 5. 17 



Surirella Turpin. 



1. Surirella Caldensis Cl. N. Sp. 



Very long and slender, linear, with cuneate ends. Al* high. Canaliculi short, 

 numerous, 4 5 in 0.01 nun. Margin striate; striaj punctate 20 in 0,01 mm. F. V. 

 linear, not cuneate. 



Length 0,108 mm. Breadth 0,013 mm. 

 PI. IV, fig. 50, """/,. 



Brazil. Caldas on Sphagnum (Dr. Hj. Mosen). Cl. et Moll. Diat. N:o 212, 

 common. 



This species comes near to S. arcta A. Schm. Atl. PI. 23, fig. 23 24 from De- 

 merara, but its canaliculi are shorter and denser. 



2. Surirella degenerans Cl. N. Sp. 



Oblong, with very broad ends and slightly contracted middle. Margins striate. 

 CostiB obsolete, consisting only of the dilated portion. Area with some scattered mar- 

 kings and striae. 



Length 0,090,072 mm. Breadth 0,0370,046 mm. 

 PI. IV, fig. 51, ^ ,. 



Gallapagos Islands (Eugenie Exp.). 



This form, which belongs to the variable section of S. lata, is related to S. laxa 

 Jaitisch. 



3. Surirella formosa Cl. X. Sp. 



Panduriform with large, rounded ends. Margin striate. Costa> abbreviate, with 

 the dilated portion comparatively large. The middle of the valve is occupied by a 

 narrow linear area, defined bv short striae. 



Length 0,22 mm. Breadth 0,11 mm. at the constriction 0,07 mm. 

 PL IV, fig. 49, "\. 



Gallapagos Islands extremely rare (Eugenie Exp.). 



This very large and beautiful Surirella does not agree with any of the many 

 forms belonging to S. toa-section hitherto figured. 



Canipylodiseus Ehb. 



1. Canipylodiseus (Ecdesiatius var.?) peramplus Cl. 



Very large, costae numerous 4 5 in 0,01 mm., equal in length, marginal. Area 

 large with a circle of puncta and with some stellate markings. 



Diam. 0,12 0,16 mm. 

 PI. IV, fig. 53, 7x. 



Gallapagos Islands (Eugenie Exp.). 



K. St. Vet. At lUndl Band. IS N:o 3. O 



