814 PROCEEDINGS OF THE NATIONAL MUSEUM. 



PHACOIDES (BELLUCINAi CANCELLARIS Philippi, 1846. 



Cerros Island, west of Lower California, and south to the Gulf and* 

 to Panama, in 5 to 80 fathoms. 



An elt>ua,itly sculptured species, with analogues on the Atlantic coast 

 and in the China seas. 



Notes.— The Liwina crlstata of Recluz (not of Smith, 1885), is a 

 TeUidora, near T. Burneti Broderip and Sowerby, but found on the 

 Atlantic coast. Lucina pidchella C. B. Adams, 1845, not Grzybowski, 

 18!>!», is a Strigilla. Lucina corrngnfa Deshayes, 1843, is credited i 

 by him to California, but really belongs to the Indo-Pacific fauna, and 

 has been collected at Singapore. It is Lucina jduUpplnar urn Hanley, 

 1850. Lucina sulcata Reeve, 1850, which has some external similarity 

 to Loripes clausm Philippi, is regarded by Mr. E. A. Smith as iden- 

 tical with L. argentea Reeve, from the Moluccas, and appears to have 

 the characters of Phacokles. Laclna cariha'a d'Orbigny, of Beau's 

 catalogue of the shells of Guadeloupe, is apparently ix'^nomen mahnn] 

 as I have not been able to And any description of it in the literature. 



A Lucina oerstedfi of Morch is listed from the AVest Indies in the 

 Poulsen catalogue, but it is probably a manuscript name, and no shell 

 so laljcled now appears in the Poulsen collection at Christiania, accord- 

 ing to Dr. Collett. 



Genus DIVARICELLA von Martens, 1880. 

 This is Cydas of Morch, 1853, not of Lamarck, ITlM*; Egraca (sp.) 

 of Leach, 1852; LucineUa Monterosato, 1883; Loripes and Lucina 

 (sp.) of various authors. Type, D. angulifera von Martens = Lucina 

 ornata Reeve, 1850, not of C. B. Adams, 1852, Mauritius. 

 This genus is divisible as follows: 



Section Diraricella s. s. 

 Valves suborbicular, convex, subequilateral, with inconspicuous 

 beaks, no dorsal areas, two cardinal teeth in each \'alve, the laterals 

 \arial)le, the posterior distant, usually obsolete; the anterior feeble, 

 adjiuvnt; ligament and resilium set in a groove, but not internal, the 

 excavated striae forming an angle on a line radial from the beaks. 

 Type, I), ornata Reeve. 



Section Ponipholigina Dall. 

 Valves extremely tumid, the umbones sul)spiral, the teeth cyclo- 

 dont, anterior and posterior dorsal areas indicated. Type, Lucina 

 gibba (h-ay, W. Africa. 



Section Bourdotia Dall. 

 Valves very inequilateral, suh(iuadrate, the antei-ior end produced, 

 the anterior dorsal margin concavely arcuate; a single minute cardinal 

 m each valve; laterals obsolete; the excavated external sulci arcuate, 

 not angulate. Type, Lucina Bourdoti Cossmann, 1882, Parisian 

 Eocene. 



