STYLOBIBLIUM. 



359 



Fig. log. 

 Salacia Boryana. 



Salacia Pant, 1889. 



Dr. Pantocsek in his Bacill. Ung., 1889, p. 68, 

 gives the following diagnosis of the sub-genera 

 Salacia : 



" Frustula a latere vis a rectangula, cum angulis 

 obtusis, valde elevata, convexa, tabulata, in fascias 

 compressas conjuncta, cum dissepimentis abreviatis 

 transversis, longioribus perpendicularibus,. inflatis et 

 lineis perpendicularibus striolatis. Valva elliptice- 

 lanceolata, cum dissepimentis transversis, ad polos 

 cum spacio hyalino nudo ; spacium interseptale 

 striolatum." 



He admits one species, S. Boryana, which is figured in the text after one 

 of my photographs. 



On the grounds that the name of Salacia had previously been given by 

 Linneus to a genus of the Phanerogamia, Professor De Toni has altered the 

 name from Salacia to Castracania. As there cannot be any confusion between 

 the two I do not see the necessity of the change. But I only notice the 

 genus Salacia as a memorandum, as I consider that ^. Boryana should be 

 included in the genus Tetracyclics. The species presents the closest affinity 

 with T. rhombus. 



GENUS 70. STYLOBIBLIUM EHR, 1845. 



Fig. no 

 Stylobiblium divisum. 



Valves orbicular, furnished with 

 costs, without pseudo-nodules. Frus- 

 tules cylindrical, free, furnished with 

 numerous internal septa. 



This genus only includes four species, 

 all fossil ; one from Japan, the other three 

 from Oregon. 



The figure opposite represents 6". 

 divisum Ehr. from Oregon, taken from 

 one of our photographs. 



