72 BULLETIN OF THE 



can properly be called a "slit" in the mantle. There is a sinuosity of the 

 elastic border of the mantle, which often disappears after death or immersion in 

 alcohol. The long clavate penis of the male lies nearly under the sinus in 

 most species, and the existence of the sinus may facilitate copulation, but this is 

 still somewhat doubtful. 



The band left on the outer surface by the curves of the lines of growth 

 across the sinus has frequently to be referred to in descriptions, and some term 

 has been needed which shall, without too much circumlocution, serve to in- 

 dicate this feature, which occurs in so many molluscan shells. I have else- 

 where proposed to use for the purpose the term " anal fasciole," which I trust 

 may prove as convenient as the term " siphonal fasciole," introduced some 

 years since by Gill, has been for a similar feature on the outer side of the canal 

 in many Gasteropods. This term " anal fasciole" for the band or trace behind 

 the notch has been approved by Dr. Paul Fischer and other experts, and will 

 be used when necessary throughout this Report. 



Genus PLEUROTOMA Lamarck. 



Subgenus PLEUROTOMA s. s. 



Pleurotoma albida Perry. 



Pleurotoma albida Perry, Conchology, expl. pi. xxxii. fig. 4, 1811. 



Pleurotoma virgo Lamarck, An. sans Vert., VII. p. 91, 1822; ed. Deshayes, IX. p. 



350, 1843 ; Tryon, Man., VI. p. 168. 

 Buccinum sinuatum Martyn, Univ. Conch., pi. xciv. right-hand figure, 1789 (not of 



Born). 

 Turris Candida Humphreys, Mus. Calonnianum, p. 34, 1797 {fide Dillwyn). 

 Murex tornalus Dillwyn, Cat. Shells, II. p. 715, 1822, ex parte. 

 Murex virgo Wood, Index Test. Murex, No. 63, pi. xxvi., 1818. 

 Pleurotoma kaitensis Sowerby, Quart. Journ. Geol. Soc, VI. p. 50, 1849. 

 Pleurotoma virgo Moore, Quart. Journ. Geol. Soc, IX. pp. 129, 130, 1853. 

 Pleurotoma Barretti Guppy, Quart. Journ. Geol. Soc, XXII. p. 290, pi. xvii. fig. 6 



(bonum), 1866. 

 Pleurotoma antillarum Crosse, Journ. de Conchyl., XIII. p. 34, pi. i. fig. 8, 1865, not 



of Orbigny (young shell). 

 Pleurotoma Jehlcii Crosse, op. cit., p. 33, pi. i. figs. 6, 7, 1865 (var. young). 

 Turris virgo Gabb, Santo Domingo, p. 205, 1873. 



Habitat. Off Sombrero, in 54-70 fms. ; off Havana, in 250 fms.; Barbados, 

 100 fms. ; Station 3G, Gulf of Mexico, in 84 fms. ; Station 132, near Santa Cruz, 

 in 115 fms.; Station 167, in 175 fms., mud, near Santa Cruz; Station 206, off 

 Martinique, in 170 fms.; Station 2G2, near Grenada, in 92 fms. Also at U. S. 

 Fish Commission Station 2120, in 73 fms., mud, off Grenada; Station 2414, 

 living, in 26 fins., sand, between Tampa Bay and Dry Tortugas. P. albida var. 

 tellea at Stations 2402 and 2404, in 60-1 1 1 fms., mud and sand, between the 

 delta of the Mississippi and Cedar Keys, Florida. 



