822 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiii. 



nidiiil sulci; ])eak.s nearly eeiitrul, small, recurved: lunule small, nar- 

 row, impressed, confined to one valve, usually the right; escutcheon 

 absent, ligament iioi'mal hut feeble; teeth normal hut small and deli- 

 cate, the laterals tending to obsolescence; adductor and pallial scars 

 normal, the interpallial space with a strong oblique sulcus; interior of 

 the disk more or less radially striate; margins crenulate below. Alt. 

 17.5, Ion. 19.0, diam. 7.5 mm. 



Dredged off the coast of Cul)a in the Gulf of Mexico, in 84 fathoms. 



CODAKIA (JAGONIA) PORTORICANA, new species. 



(Plate XXXIX, fig. 6.) 



Shell small, plump, oblique, inequilateral, white or yellowish; ante- 

 rior end larger, produced downward and forward; ])osterior end 

 shorter and smaller; surface sculptui'ed with numerous radial sulci, 

 separated by wider flattish interspaces crossed by rather regulai-, mod- 

 erately separated, concentric elevated threads, the radials obsolete on 

 the inconspicuous doi'sal areas; lunule elongated, moderately impressed, 

 escutcheon short, narrow, inconspicuous; beaks high, rather small, 

 apically smooth and polishi^d. prosogyrate; hinge normal, delicate, the 

 laterals in the right Nahc well developed; ligament fee])le, short; inte- 

 rior more or less striate, radially; basal margin finely crenulate. Alt. 

 G.7, Ion. 7.5, diam. 0.0 mm. 



The figured specimen, the largest valve ol>tained, is from San -Juan 

 Harbor; smaller ones were dredged in the liarboi- of Ma\'aguez. 



This inconspicuous little sp(»cies appears to be rare, and comes near- 

 est to Jagoiua coxtnta d'Orbigny. than which it is more finely and 

 evenly sculptured, beside being a more tumid and smaller shell. In 

 preparing the Porto Rico report this species was overlooked. 



CODAKIA (JAGONIA) MEXICANA, new name. 



(Plate XL, fig. 6.) 



One of Reeve's figures in the Iconica (fig. 33) appears to represent 

 this species, which is very similar to the West Indian ([. orlnculata 

 Montagu. 1 find, however, on careful examination that in the west 

 coast shell the lunule is narrower, longer, and less deeply impressed 

 than in C. ophiculata^ the shell is more delicate, thinner, and more 

 flattened toward the lower margins, the sculpture is more regular and 

 the concentric threads less crowded, so that while the difi'erence is not 

 great the efiect in C. mexicana is much more elegant; toward the ends 

 it has the radials stouter and with wider interspaces, and with the 

 sculpture on the dorsal areas less distinct from that on the disk than 

 it is in the West Indian form. It is most commonly labeled Luclna 

 hella Conrad, in collections, and by Carpenter was named L. jjectmata^ 

 though it is not the jyectinata of Gmelin or C. B. Adams. A full- 

 grown specimen measures: alt. 21, Ion. 23, diam. 10. nnn. 



