274 BUCCIXID-E. 



Shell oral, spirally sculptured ; base strengthened by an 

 oblique ridge : epidtrmis, if present, velvety or membranous: 

 spire short ; body- whorl consequently large : mouth oval : pillar 

 twisted: canal short and recurved: operculum homy, oval, 

 never spiral, increasing by concentric or elliptical layers ; 

 nucleus placed withiu the edge, at the outer side of the mouth. 



The ^Purpuriferes ' of Lamarck. Adanson noticed that 

 the shell of the male is usually smaller than that of the 

 female, and that the former has a longer spire and more 

 whorls although not so tumid. He included this family 

 and the Muridda in his genus Purpura. Miiller out- 

 bid Adanson by composing his genus Tritonium of the 

 same extensive groups,, and thi'owing Aporrkaidce and 

 Xassidce into the bargain; his Buccinum is owe Limnaa. 

 The egg-cases are membranous ; those of Buccinum are 

 cup-shaped, and piled one upon another like the cells 

 of a honeycomb ; in Purpura they are separate, resemble 

 grains of barley, and are placed upright. Although the 

 lingual riband in all the Rhachiglossata (which com- 

 prise the Siphonobranchiata) is armed with spinous 

 teeth, none of this division appear to have the jaws 

 (cheek-plates or immoveable mandibles, Morch) with 

 which the Tfeiiioglossata (including the Pectinibran- 

 chiata) are provided. The muscle by which the body 

 is attached to the pillar of the shell in families of the 

 present order is unusually strong. 



Genus I. PUR'PURA* Bmguiere. PL V. f. 1. 



Shell conic-oval, thick, destitute of an epidermis: spAre 

 sharp-pointed: ivhorls more or less compressed: outer lip tuber- 

 culated within : pAllar flattened, sloping inwards with a sharp 

 edge : cuiial narrow. 



* The name of a snell-Ssh from ■which the Tjrian dye {irop<pvoa} -xas 

 extracted ; erroneously applied to this genus. 



