OF CONCHOLOGY. 37 



Other organs. — The eyes in this species are exceedingly 

 minute, so as to be invisible to the naked eye unless well trained. 

 They are circular and deep seated. In alcoholic specimens the 

 skin must be carefully shaved away and examined by transmitted 

 light in order to find them at all. They can be of little real use 

 to the mollusk, as vision must be out of the question, and they 

 can hardly be more than sensible to light and darkness. No 

 organs of hearing were detected. 



This dissection does not agree with the figures of Quoy 

 (*S'. Diemenensis), which, as is the case with many of Quoy's 

 figures, seem to owe a good deal to the imagination of the artist. 

 I am inclined to refer the differences, especially those of the 

 genitalia, rather to this cause than to any real diff"erences of 

 structure between the species. 



SiPHONARiA PELTOiDES, Dall ex Cpr. Plate 4, fig. 11, a, b." 



JVacella peltoides, Cpr., Ann. and Mag. Nat. Hist. 1804, i, p. 



474, No. 15. Sup. Rep. Br. Ass. 1863, pp. 418 and 545. 

 Nacella, sp. indet., Cpr., Maz. Cat. No. 262, p. 202. Rep. 



Br. Assoc. 1856, p. 252. 

 Naeella{?) subspiralis, Cpr., Proc. Cal. Acad. Sci. iii, p. 213, 



1866. Sup. Rep. Br. Assoc. 1863, p. 612, No. 65; p. 

 650, No. 240 (name only). Coop. Geogr. Cat. Cal. Moll, 

 p. 23, No. 443, 1867. 



Nacella? vernalis, Dall, MSS. 1866. Stearns, Shells of Pu- 

 rissinia and Lobitas, Proc. Cal. Ac. Sci. Vol. iii. p. 345, 



1867. Hepburn's Shells, do., p. 284. Shells of Santa 

 Barbara, do., p. 344. 



S. testa tenuissima, conica, parva ; vertice subacuto, subpos- 

 tico ; Isevi seu interdum costulis paucis, obsoletis radiatim vix 

 ornata; epidermide tenui subfusco seu viridi clari, non Inevi, 

 fugaci ; costa pulraonali intus et extus valde inconspicua; testa, 

 extus subfusco cum luteo-virido radiatim ; intus Isevissime. Lon, 

 •48, Lat. -36, Alt. 23 in. 



Habitat, Monterey, Purissima, Lobitas, Santa Barbara and 

 San Diego, California. Gallapagos Islands, Dr. Hable. Maza- 

 tlan (Reigcn coll.), Cpr. Cape St. Lucas, Xantus. Catalina 

 Id., Cooper, 6 — 10 fms., dead. 



Shell small, thin, conical ; apex recurved, nearly in the median 

 line, more or less acutely pointed ; generally somewhat eroded 

 in old specimens. Epidermis thin, not polished, smooth, brown- 

 ish red on the apex and in dead shells ; in fresh or young indi- 

 viduals of a bright grass green, somewhat wrinkled and fre- 

 quently overlapping the border of the shell ; fugacious. Shell 

 smooth, reddish brown, with fifteen or more light yellow green 



