MAZATLAN UNIVALVES 517 



662. PiSANIA SANGUIKOLENTA, Ducl. 



Purpura sanguinolenta, Ducl. in Guer. Mag. Zool. pi. 22, f. 1, 



1833. 

 Buccinum sanguinolentum, Ifhe. iu Zelt.f. Mai. 1847, p. 180, 



no. 11.— C. B. Ad. Fail. Shells, p. 72. no. 64. 

 Pollia lieemastoma, Gray, Zool. Beech. Voy. p. 112, 1839. 

 Buccinum hgemastoma, Eve. Conch. Ic. pi. 7, f. 46. 

 Buccinum Janelii, Val. Voy. Ten. Moll. pi. 6, f. 1, la-c. 1846. 

 Tritonium verrucosum, Mice. ms. loo. cit, 

 (Cantharus) Tritonidea sanguinolentus, H. Sc A. Ad. Gen. i. 85. 



This extremelj' beautiful species is constantly distinguisked 

 from P. gemmata by its small size, colour, and detads of sculp- 

 ture. The three nuclear Tvhirls are smooth and subtransparent ; 

 the succeeding ones, as iu P. gemmata, but less indented. The 

 last two have in the middle of each whirl about nine elongated 

 projecting tubercles rather than ribs, Avith a broad depression 

 between these and the subsutural gi'anulose line. Spiral scidp- 

 ture faint except on the tubercles, where the narrow tips of the 

 principal lirulae are brownish red : between each are 6-8 fine 

 striulae. Epidermis very thin, deciduous. Surface frequently 

 encrusted with Bryozoa, Annelids, and very rarely with cor- 

 alline. One young fresh specimen was found on Spondylus, 

 Labrum as in Pisania gemmata, with a very stout tubercle 

 behind the posterior canal : inside more or less grooved, ending 

 in sharp serrations, generally projecting in pairs between the 

 principal lirulse. Columella with one Fasciolaroid fold. Labium 

 covered aU along with numerous warts, white on a blood- red 

 ground, which vary in shape and size. Canal short. Colour 

 a prevailing greenish brown, with brownish red on the tips 

 and round the mouth. Operculum scarcely differing from that 

 of P. gemmata, but rather flatter, with the external groove 

 scarcely marked. An adult, which appears as if the animal 

 had been starved, with the tubercles scarcely developed, 

 measures long. '72, long. sp'n'. "25, lat. "44, div. 60". 



An unusually large sp. 1"26, „ '56, „ '8, „ 57°. 



Sab. — Panama ; under stones at low water ; Cuming. — Do. ; 

 and Taboga, same station, and probably lower, very rare ; 

 C. B. Adams. — Mazatlan ; rare ; L'xiool Col. 



Tablet 2461 contains 5 sp. in procesi of growth. — 2162, 4 sp. 

 adult, different sizes. — 2463, 3 sp. encrusted. — 2464, 3 opercula, 

 of which one is ovate, distorted, nucleus subccutraJ. 



April, 1857, WW 



