360 GASTROPODA. [Pectin ibranfMa. 



Genus 1. MITRA, Martyn. 1784. 



Mitra, Martyn, Un. ('onch., i, f. 19. First species : J/. tessellata, Martyn. 

 Thiarelld, Swainsou, 1840. Mitmria, Rafinesque, 181o. Mitrolithe.s, 

 Kriig, 1823 (fide Tryon). 



Radula triserial ; the central tooth narrow, multicuspidate ; the 

 laterals very broad, multicuspidate ; the cusps sharp and subequal. 



Shell fusiform or oval, solid : spire elevated, pointed ; aperture 

 narrow, notched at the base ; outer lip not reflected, thickened and 

 smooth within ; columella transversely, somewhat obliquely plicate. 

 No operculum. 



Over two hundred species, mostly from tropical, and temperate seas, 

 have been described. The Philippine Islands are particularly rich in 

 these elegant and beautiful shells. 



Fossil in the Tertiary. 



KEY TO Si'Ki IES. 



A. Shell fusiform, uniformly dark brown, without axial sculpture, 



spire higher than the aperture . . . . . . . . rurhnnaria. 



B. Shell shortly fusiform, fulvous with large white spots, upper 



whorls axially costate, spire lower than the aperture . . nlbopicia. 



( '. Shell very small, shortly fusiform, greyish-white, spirally grooved 



and axially plicate, spire half the height of the aperture . . Hfdhyi. 



1. Mitra albopicta, K. A. Smith, 1898. Plate 46. tig. 9. 



Mitra ulho[>irta, E. A. Smith, P. Mai. S., iii, 1898. 21. f. 5 in text. 



Shell shortly fusiform, solid, shining, fulvous with irregular white 

 spots, upper whorls distinctly axially costate. Sculpture consisting 

 of a few fine spiral grooves below the suture, and narrow oblique 

 spiral riblets on the base : the three whorls below the protoconch with 

 slightly oblique, close, broadly rounded axial costa? ; the intestices 

 much narrower ; on the succeeding whorls the riblets are irregular, 

 and disappear more or less. Colour fulvous, with short irregular zig- 

 zagging white spots below the suture and upon the base, a revolving 

 series of small elongate white spots on the lower third of the body- 

 whorl, aperture light purple inside, inner lip white. Spire acutely 

 conic, a little lower than the height of the aperture ; outlines lightly 

 convex. Protoconch very small, the minute nucleus papillate, excentric. 

 Whorls 7, slightly convex, first slowly increasing, the last a little more 

 than two-thirds of the whole height ; base somewhat contracted on 

 the side of the pillar. Suture moderately deep, impressed. Aperture 

 oblique, high and narrow, angular above, a little narrowed below, 

 truncated, and slightly notched. Outer lip subvertical. almost parallel 

 with the columella. with a rather blunt edge, lightly thickened inside 

 above, smooth. (Columella slightly oblique, with 4 equidistant elevated 

 plaits, the uppermost almost horizontal, the others oblique ; the 

 first is slightly smaller than the two in the middle, the lowest con- 

 siderably less conspicuous. Inner lip verv thin, narrow, sharply 



