252 ADDITIONS-RECENT SPECIES. 



circular. The longitudinal ridges are fine and numerous, number- 

 ing about twenty-five to thirty at an inch from the apex. Towards 

 the anterior end intervening riblets appear, so that the interstices, 

 which above are broader than the lirse, become narrower. The 

 lines of growth are distinct, and on crossing the riblets towards the 

 posterior end produce a granulated appearance ; the ridges are much 

 smoother anteriorly and less elevated. The length of the fissure is 

 variable, but this is probably chiefly due to damage. In the most 

 perfect specimen it is 13 millimetres in length and rather more than 

 half a millimetre in width. All three specimens exhibit reparation 

 of injuries at the anterior end, and in two the posterior extremity 

 has been broken off; these injuries are probably done by fishes or 

 crustaceans. The shells are whitish, but coated with a dark brown 

 earthy deposit. The Rev. Professor H. M. Gwatkin informs me 

 that the radula is quite normal, and that the figure given by Sars of 

 Antalis striolata closely represents it, except that in the present 

 species ' the central tooth is a little wider and the inner edge of the 

 lateral makes a smoother muzzle.' " 



D. EXUBERANS LoC. (p. 79). 



By oversight, the date " 1847 " instead of 1897, appears in the 

 reference line below this species and D. scamnatum, on the same 

 page. 



D. RECTUM Gmel. (p. 81). 



The locality " India" is incorrect, the species being an Italian 

 Pliocene fossil which also occurs living in deep water in the eastern 

 Atlantic, according to Fischer. D. delessertianum is a synonym. 

 See p. 213. 



D. SEMIPOLITUM B. & S. (p. 91). 



Additional localities are : San Pedro, California ; Margarita Bay 

 on the Pacific coast of Lower California. A specimen from Boca 

 de los Pedras, in the Gulf of California, measures: length 34, diam. 

 3-2 mill., and is lemon-tinted toward the apex (No. 46,203 U. S. 

 Nat. Mus.). Another from San Ignacio Lagoon, on the ocean 

 coast of the Peninsula, measures length 34, diam. 2*7 mill. 



D. EBURNEUM Linn. (p. 115). 



Reported under the name " politum Lam.," from the Gulf of 

 Suez at 10 meters depth by Issel, Mai. Mar Rosso, p. 236. We do 

 not vouch for the correct identification of the specimens. 



