TETHYS—WEST AMERICAN. 87 
A. lessonii Rane. Hist. Nat. Aplys., p. 60, pl. 14.—LeEsson, 
Voy. autour du Monde, ete., La Coquille, Zool., ii, pt. 1, p. 295 
(1830). 
T. rvca d’Orbigny. PI. 19, figs. 29, 30,31. 
Extended animal as much as 20 em. long. Moderately length- 
ened, elevated, flabby, very ventricose. Cephalic portion elongated, 
on a very short neck; buccal lobes very long and very wide, flat- 
tened and inrolled at the end, which is thin, sharp and strongly 
ridged. Tentacles long, subconic, obtuse and slit at the ends, placed 
slightly behind the middle of the interval between buccal and swim- 
ming lobes. Eyes visible, in front of the tentacles. Mouth placed 
at the lower part of the fissure separating the buccal lobes. Foot 
narrow, strongly wrinkled, acuminate behind. Swimming lobes 
very large, united and much prolonged behind the gill. Mantle 
swollen, oblong, smooth, with a very small round aperture in the 
middle ; posteriorly it is produced in a very long, wide and thin 
tongue. 
Color, a beautiful violet tint, with rounded white spots on the 
sides of the front part of swimming lobes, and several larger, more 
regular oblong and spaced on the neck and head, usually two be- 
hind the tentacles and four in front on each side, on a line with the 
forward insertion of the swimming lobes. Swimming lobes marked 
along the inside edge with a narrow border of clear rcse-violet, 
flanked by large rounded and angular white blotches on a purple- 
brown ground. Mantle uniform violet. Gill purple violet. Pre- 
served in alcohol this species retains the entire pattern of spots, 
but the ground tint becomes blackish, dotted with blackish, 
Shell amber colored with corneous edge. 
Callao Bay. 
Aplysia inca ORB., Voy. dans l’Amér. Mérid., p. 207, pl. 14, f. 13. 
—A. incus Sows., Conch. Icon., f. 28. 
This species differs from T. /essoni in pattern of coloring, and the 
non-tubular mantle foramen. 
T. CHIERCHIANA Mazzarelli & Zuccardi. 
This new species is based upon two specimens from the island of 
San Lorenzo, Peru. The principal character of the species consists 
in the presence of a contractile, strongly-developed papilla in the 
center of the mantle, at the point where there is ordinarily an aper- 
ture. This papilla is swollen at base, narrowed toward the sum- 
