23 



Peiiploma. 



2 praetcnuis Penn. 

 2 tenera Fscbr. 

 1 trapezoides Lm. 

 undulata Verril. 



883. Gen. Pelopia H. Ad. 



brevifrons H. Ad. 



884. Gen. Alicia Ang. 



angustata Ang. 

 elesixntula Ang 



35. Gen. Lyonsia Tuit. 



Syn. Periploma Rang. 

 „ Osteodesma Dsb. 

 „ Magdala Leach. 

 „ Pandorina Scacc 

 „ Iliatella Brown. 

 „ Myatella Brown. 

 „ Tetragonostea Dsb. 



1. Sect. Lyonsia Turt. 



2. „ Entodesma Pbl. 



3. „ Lyonsieila Sars. 



4. „ Silenia Smth. 



auatina Gray. 



arcaeformis Mrts. 



arctica Gray. 

 1 arenosa Möller. 

 1 Vr. Sibirica Leche. 



argentea Jeffi'. 



bracteata Couth. 



Brasiliensis Couth. 



brevifrons Sow. 



1 Califoriiica Conr. 



2 Chilensis Phl. 

 corbuloides Pet. 



1 corruscans Scach. 

 1 cuneata Gray. 

 1 diapbana Crptr. 



elomjata Gray. = xVor«' 



flabellata Gld. 



1 Floridana Conr. 

 fonnosa Jeffr. 



2 gibbosa Hanc. 



3 grandis Smth. 

 1 hyalina Conr. 

 3 Jeffreysi Friele. 

 1 Morgan! Chapcr. 

 1 navicula Ad. et Rv. 

 1 nitida Gld. 



Britan. 

 Gascogne. Tet. J. 1882 p. 53. 

 Brasil. 

 U. S. Amor. Mayer ZJB. 1885. 



P. Jaeks. 

 Wats. B. 



Proc. 18G8 r. n. 



Proc. 1867 p. 008. 

 Proc. 1867 p. 914. 



Ad. Gen. 2 p. 363. 



