246 ZEIDORA. 



. Numerous specimens of this little shell are before me. They seem 

 to differ from the F. rostrata as described and figured by Seguenza, 

 in having the apex rather more central and the minute tubercles ar- 

 ranged in " oblique sweeps " rather than in horizontal rows. The 

 great variation of rostrata as shown in Seguenza's several excellent 

 figures, and the fact that Dr. Dall quotes Watson's pi. 4, fig. 10 as 

 an illustration of his F. triangulata, while the said figure is in fact 

 a copy of one of Seguenza's illustrations of the typical form of his 

 fossil, causes me to hesitate to separate the recent from the fossil 

 forms. 



P. GRANULOSA Jeffreys. PI. 27, figs. 71, 72. 



Shell roundish-oval, conical, but somewhat depressed except to- 

 wards the apex, thin, opaque, and lusterless ; sculpture, very 

 numerous fine and delicate striae which radiate from the apex or 

 beak, and are closely covered with minute tubercles; some of these 

 striae do not quite extend to the apex, and are alternately larger and 

 smaller ; the apex is irregularly tubercled ; margin finely crenated 

 or notched by the striaB ; foramen nearly circular ; inside smooth, 

 but not polished ; septum triangular, covering about half only of the 

 foramen on the underside. Length 0*125, breadth O'l inch. (Jeffr.) 



In my paper on Norwegian Mollusca (' Annals and Magazine of 

 Natural History' for June, 1869), I named this remarkable shell as 

 F. papillosa of Seguenza ; but I afterwards found that I was mis- 

 taken as to the species. The shell now described is more delicate, 

 and the sculpture is much finer, with regular and close-set striae 

 which are studded with far more numerous and minute tubercles. 

 The foramen is circular in the present species, and triangular in F. 

 papillosa. 



North Atlantic; Drobak, Norway, 50 fms. 



F. granulosa JEFFR. P. Z. S. 1882, p. 675, t. 50, f. 9. 



Genus ZEIDORA A. Adams, 1860. 



Zeidora A. AD., Ann. Mag. N. H. 1860, p. 301, type Z. calceo- 

 lina. AD. & SOWB., Thes. Conch, iii, p. 209. SOWB. 2o, in Conch. 

 Icon. vol. xix, 1873. WATSON, Challenger Gastrop. p. 36. Zidora 

 FISCHER, Manuel, p. 861. Crepiemarginula SEGUENZA, Forma- 

 zione Terz. di Reggio-Calabria, p. 273, type C. reticulata Seg. Z, 

 seguenzce Wats. 



Shell oblong, depressed, the apex recurved, posterior; fissure an 

 open slit in the front margin ; interiorly provided with a plate or 





