804 PROCEEDINGS OF THE NATIONAL MUSEUM vol.xxiii. 



in his text, but on the Plate lxxxiv of the atlas, where it is tigured, 

 the name is L\icma hra-slliana d'Orbigny. It is not the Lucina 

 hrasiliensis of Philippi, 1848. 



The name Loripcs has been veiy generally applied to the large, gloljose 

 edentulous shells which are properly known as typical Luclna^ but 

 these have not an internal resilium. Loripes leihs of Verrill and Smith, 

 1880. and L. compressa Dall, 1881, should be placed in the genus 

 Myrtma^ as the}' also are destitute of the internal resilium which is the 

 chief characteristic of the genus Loripes. 



Genus MYRT^^A Turtou, 1822. 



This is CyracluBa Leach, 1852, and OrtyyUi (sp.) Brown, 1827. 

 Type, Venui< spinifcra Montagu, 18<>;-^. Northern Europe. 



Shell ovate or subroctangular, not inflated, the dorsal areas obsolete, 

 sculpture chietiy concentric; lunule and escutcheon long and narrow; 

 ligament and resilium deep-seated, but not internal, anterior adductor 

 scar rather sliort; hinge with the right anterior cardinal normally 

 absent and the left laterals frequently obsolete. 



Two s(H'ti()ns are discriminal)le: 



Myrtaea s. s. Shell of moderate size, with purely- concentric 

 scidpture. 



Eulopia Dall, 1901.. Shell small, with radial vermicular sculpture 

 between stronger concentric lamellae Type, Lnv'nia m<jrinata Dall, 

 1886. 



This group appears in the Oligocene of Bowden, Jamaica. 



The American species are as follows: 



MYRT^^A LENS Verrill and Smith, 1880. 



From Cape Cod, Massachusetts, south to the Antilles and Rio de 

 Janeiro, Brazil, in 50 to 464 fathoms, bottom temperatures ranging 

 from 41.5° to 46.5° F. 



This is Lorqh'-s Jcnn of Verrill and Smith, 1880, but not Lncl/in lens 

 of Roemer (Nordd. Kreidegeb.), 1841, nor Luclna lens of H. C. Lea 

 (Virginia miocene) 1845. 



MYRTiEA COMPRESSA Dall, 1881. 



Cuba and Sombrero, West Indies, in 72 to 424 fathoms. 



This is Lorlpea amipressa Dall, 1881, and may prove to be an 

 extremel}'^ transverse and compressed variety of J/, lens Verrill and 

 Smith. 



MYRTiEA PRISTIPHORA Dall and Simpson, 1901. 



Porto Rico, Santa Lucia, Bar])ados. and (irenada, in ?><) to 300 

 fathoms. 



Described and figured in the Porto Rico report of the U. S. Fish 

 Commission. 



A 



