HARP A. 



Plate I. 



Genus Harpa, Lamarck. 



Testa ovalis, ventricosa, ad basim emarginata ; spird brevi, 

 latissime canal iculatd, apice elato, acuto ; anfractibus 

 longitudinaliter costatis, costis plus rn.inv.sve numero- 

 sis, arcuatis, parallelis, politis, superne aculissime mu- 

 cronatis ; aperturd ovato-oblongd, ampld ; columella 

 subexpansd, lavissimd, politd ; labro incrassato, cos- 

 tam ultimata formante. Operculum nullum. 



Shell oval, ventricose, emarginated at the base; spire 

 short, very widely canaliculated, apex raised and 

 acute ; whorls longitudinally ribbed, ribs more or 

 less in number, curved, parallel, polished, and 

 sharply pointed at the top ; aperture ovately oblong, 

 large; columella somewhat expanded, very smooth, 

 polished ; lip thickened, forming the last whorl. 

 No operculum. 



Few groups of mollusks present a more complete ge- 

 neric cast of character than that of the Harpa, whether 

 as respects the shell or its animal inhabitant. The most 

 characteristic features of the shell are so perfectly di- 

 stinct from those of the proximate genera, that one is 

 almost tempted to imagine that there must be a gap, on 

 either side, in the system which nature has omitted to 

 fill up, and the animal, according to MM. Reynaud and 

 Quoy, exhibits quite as isolated an association of cha- 

 racter. The foot or locomotive disk of this mollusk is 

 described by the enterprising malacologist of the Astro- 

 labe to be so large and muscular that it is incapable of 

 entering the shell, and the animal is said to have the 

 power, when irritated or in any dangerous emergency, 

 of spontaneously divesting itself of so much of this mus- 

 cular disk as it is unable to protect. 



The Harpa. are not very numerous in species, and as 

 they run apparently very much into each other, it has 

 been thought extremely difficult to identify them accord- 

 ing to the limits established by Lamarck. Great errors 

 have been on this account promulgated in their specific 

 arrangement ; no two shells for example can be more 

 clearly distinct than the many-ribbed Harpa impenahs 

 and the many-ribbed variety of the Harpa ventricosa; 

 and the Harpa conoidalis may certainly be distinguished 

 from the latter, with a moderate exercise of discrimina- 

 tion, though all these have been, and are still, confound- 

 ed together. The acute perception of Lamarck, how- 

 ever it may have failed him at the close of his useful life, 



detected certain specific characters, the value of which 

 an extensive series of specimens, instead of generating 

 confusion, has enabled me to estimate ; and I have se- 

 lected the " Harps" thus early for illustration, not from 

 any accession of novelty, but from a desire to perpetuate 

 Lamarck's arrangement of them. 



No shells have perhaps excited more universal admi- 

 ration than the " Harps," so rich and delicate in then- 

 colouring, so symmetrical in their proportions. The 

 longitudinal ribs, which constitute their most striking 

 peculiarity, are analogous in structure to the varices of 

 the Canalifera, each forming in its turn the margin of 

 the aperture ; and like them, they are deposited by the 

 animal to protect the outer lip during a season of rest, 

 the greater multiplicity of ribs indicating the more pe- 

 riodical growth of the shell. 



The Harpa, says Broderip, are taken at the Mauritius 

 on sand banks with a small rake to which a net is at- 

 tached when it is low water, at night and at sunrise ; it 

 is conjectured that at those times they are out on their 

 feed. 



Species 1. (Fig. a, Mus. Townley; Fig. b, Mus. Cuming; 



Fig. c, Mus. Steere.) 

 Harpa nobilis. Harp, testd ovatd, subventricosd, basim 

 versus attenuato-coarctatd, griseo-rosaced, fusco al- 

 boque arcuato-arliculato, maculisque grandibus pur- 

 pureo-sanguineis, quadratis, perpaucis, vivide pictd ; 

 costis latiusculis, lineis nigris capillaribus transversim 

 fasciculatis. 

 The noble Harp. Shell ovate, rather ventricose, at- 

 tenuately contracted towards the base, greyish pink, 

 vividly painted with arcuately articulated brown 

 and white, and a very few large square spots of 

 purple-crimson ; ribs rather wide, crossed here and 

 there with a number of black hair-like lines. 

 Rimphius, Mus., pi. 32. fig. L. 

 Lamarck, Anim. sans vert., vol. vii. p. 256. 

 Cithara nobilis, Martini. 

 Buccinum harpa, var. e, Bruguiere. 

 Hab. Island of Ticao, Philippine Islands (found in sandy 

 mud in deep water) ; Cuming. 

 The Harpa nobilis is one of the most distinct species 

 of the genus. It is very much contracted in form, and 

 the painting is peculiarly distributed ; the ribs are vi- 



October 1843. 



