284 Mr. Swainson's Monograph 



In size, shape, and in^ the proportion of its spire, this beautiful 

 species resembles A. Tankervillii and glahrata. It is two inches and 

 three-quarters in length, one half of which is occupied by the spire. 

 In the thickened belts, and the concave grooves above them, it re- 

 sembles A. glabrata ; but the enamel which covers the spire forms 

 an additional belt on the shoulder of the body whorl ; the pillar is 

 nearly smooth, completely imperforate, and flesh-coloured white; 

 the concave groove is rather wide, containing two impressed lines, 

 and forms a tooth at the margin of the outer lip. The general 

 colour of the whole shell is a rich dark chestnut and highly polished. 



A magnificent specimen of this fine shell is in the possession of 

 my friend Mr. Broderip. It came from China, and has been 

 engraved for " Illustrations of Zoology," now preparing for 

 publication. 



The discovery of the two last shells unites the Ancillarite, in the 

 most beautiful manner, to the Eburna glabrata of Lamarck : before 

 they were known, this affinity appeared to me so strong that I 

 purposely refrained from associating this last-named shell with the 

 other Lamarckian Eburnce. (See Zool. 111. vol. 3. pi. 144.) Thus 

 the imperforate and the umbilicated species arc connected ; and, 

 if this connexion could be rendered more perfect, it would be by 

 a species wherein the umbilicus is only partially developed. Now 

 it is very remarkable that such a structure will actually be observed 

 in the following species : — 



2. Shell umhilicaled. 



13. Ancillaria, balteaia. Mihi. 



A lestd subumbilicatd, ovatd ; anfiactds bascUis parte superiore balteo gibbo 



conve.vo cinctd. 

 Shell sub-umbilicated, ovate, upper pari of the basal whorl with a gibbous 



convex belt. 

 Eburna balteata, testd cyUndraceo-oblonga, spird sub-conicd, anfraclu 

 ultimo superne incrassato ; inferne ballecUo. Sowerby, Genera, Fasc . 



19. pi. Eburna, f. 3, 4, optlme. 



This is a small species, scarcely ever exceeding one inch and a 

 quarter in length, half of which is occupied by the spire. Its shape is 

 thicker in proportion than that of .4. glabrata ; the upper part of the 



