342 BULLETIN OF THE 



macroscopic anatomy of the mollusca, is so great that it is astonishing that it 

 attracts so few students. 



It is probable that Scutellina will prove not to have a verge, but this is 

 not yet certain; the other families comprising this section of the super-family, 

 Addisoniidce and Cocculinidce, are known to be so provided. 



Family SCUTELLIN1DJE Dall. 

 Genus SCUTELLINA Gray. 



Scutella Broderip, P. Z. S. 1834, p. 47. (Not Scutella Lam., 1816.) 



Scutellina Gray, P. Z. S. 1847, p. 168. (S. crenulata Brod.) Dall, Am. Journ. Conch., 



VI. p. 239, 1871. H. & A. Ad., Gen. Kec. Moll., pi. lii. fig. 6 (S.ferruginea). 



Pease, Am. Journ. Conch., IV. 99, pi. xi. figs. 26, 27 (bad). 



The genus Scutellina has long been of doubtful relations. I had endeavored 

 in vain for sixteen years to obtain the soft parts in alcohol. Finally, a single 

 specimen collected on the reefs near Key West, Florida, was sent by Mr. H. 

 Hemphill, to whose admirable abilities as a collector naturalists generally are 

 so much indebted. This has enabled me to correct several errors into which 

 writers on this genus have been led, and to interpret more accurately what has 

 been not altogether clearly written. 



This group has been referred universally to the Docoglossa, to which it does 

 not belong. It has a purely rhiphidoglossate dentition, closely related to that 

 of Neritina and Helicina. It is set in its shell like the other rhiphidoglossate 

 limpets Fissurella, Emarginula, etc. ; that is, with the head turned away from 

 the apex of the shell. Its gill is situated, like that of Neritina or Acmcea, on 

 the left side above the body, and pointed to the right over the back of the neck. 

 The anal papilla and that by which the products of the renal organ are ejected 

 are situated exactly as in Acmcea. The tentacles are long and slender, the 

 eyes well developed and placed on swellings at the outer posterior part of the 

 tentacles. The distal end of the muzzle is expanded, semilunar, smooth, with 

 a continuous margin a little produced at the outer corners. The mouth is 

 small and situated in about the centre of the disk. The dental formula for 



the right side of the radula is R + (- -+- 2 -+- -)+ - ; x standing for the uncer- 



tain but large number of denticles on the first lateral, or of single uncini in the 

 compound series. The central or rhachidian tooth (R) is flat, squarish, and 

 edentulous, as in Helicina orbiculata. 



Scutellina antillarum Shuttleworth. 



Plate XXXI. Figs. 10, 11. 



? Scutellina antillarum Shuttleworth, in Poulsen, Cat. of West India Shell9, p. 14, 

 No. 930, 1878. 



The shell, the only Scutellina I have seen from the Gulf or Antilles, I sup- 

 pose to be Shuttleworth's species. It is a small thin shell, about 8 by 6 mm. 



