AVICULA. Panama Shells. 249 



Station. Sandy mud, 12 to 20 fathoms ; Cmning ! Sowerby. 



Habitat. Panama and Bay of Caraccas ; Cuming ! Sowerby : 



also Orbigny. 

 Panama ; C. B. A. ! 

 We found 1 entire shell and 3 odd valves. 



390. Lima Pacifica. 



Synonymy. 



Lima, arcuata So\vb. (non Geinitz 1840) Thes. Conch, p. 86. 



No. 15. pi. 22. f. 41-2. 1843. 



- Hanley Descr. Catal. p. 268. 1845 ? 



- Pacifica, Orb. Voy. Amer. Merid. Moll. p. 654. 1846. 



Station. Under stones at the low water mark of the spring 

 tides. 



Habitat. Guayaquil and Panama ; Cuming ! Orbigny. 

 Panama ; Hanley. 

 Panama ; C. B. A. ! 



11 At Lord Hood's I., under coral rocks ; at Panama, in sandy 

 mud ; at Guayaquil Bay ; at Guacomayo, under stones, &c., by 

 Mr. Cuming." Sowerby. 



3 specimens were found alive on the reef. 



Family AYICULID^E. 

 391. Avicula margaritifera I 



Under the name of A. margaritifera are included several 

 kindred but distinct types. It would be of great service to the 

 general subject of the geographical distribution of marine 

 species, if some one would collect authentic materials, and 

 investigate the peculiarities of the local types. 



Station. In the crevices of rocks near low water mark. 



Habitat. Taboga ; C. B. A. ! 



We found only 2 living, rather young, specimens. Probably 



JULY, 1852. 17 Ann. LYC. NAT. HIST. 



