182 PROCEEDINGS OF THE NATIONAL MUSEUM. VOL. 37. 
Distribution.—In the Patagonian and Peruvian zoological provinces 
and the West Indian region. 
The animal is normally of a pinkish white dotted with dark red, 
especially on the dorsal region. It has ten arms and an internal ‘‘pen” 
or endostyle, which is plume-shaped with symmetrical vanes, as 
represented in figure 2. This endostyle is. of a cartilaginous material 
and not shelly, as in some other genera, such as Sepia, etc. The 
details of form are well represented by the figure. 
Beside the mollusks enumerated in the above report, Mr. Coker 
collected the following species belonging to the Brachiopoda. 
DISCINISCA LAMELLOSA Broderip. 
Orbicula lamellosa Broderip, Proc. Zool. Soc. of London for 1833, p. 124; Trans. 
Zool. Soc. London, vol. 1, 1834, p. 142, pl. 23, fie. 2. 
On Mytilus (Choro) at Ancon Bay. Of no economic importance. 
Distribution —From the Island of Chiloé northward to the Gulf 
of Panama, adhering like limpets to mussels, the timbers of old 
wrecks, and even to the bottoms of vessels which remain at anchor 
for some months. They occur from low-water mark to a depth of 
9 or 10 fathoms. 
The shell is horny, rounded, and nearly flat, with a more or less 
profusely lamellose surface; the upper valve is slightly convex, the 
apex a little eccentric, the lower valve is flat, radially striate, very 
thin, and pierced by a narrow foramen through which a fleshy 
pedicel extends by which the animal adheres to solid objects. The 
color is yellowish brown, and the diameter of these shells when nor- 
mally developed rarely much exceeds 25 mm. 
LIST OF THE PRINCIPAL WORKS RELATING TO THE MOLLUSCAN 
FAUNA OF THE PERUVIAN ZOOLOGICAL PROVINCE. 
The following works are those most necessary for a study of this 
fauna, though many others have been consulted for incidental 
references. The abbreviations used in the faunal list to designate 
some of the more frequently cited works follows the title in paren- 
theses. 
BAYERN, THERESE, Princessin von. Im Jahre 1898, auf einer Reise in Siid-amerika 
gesammelte Mollusken. Nachr. Deutsche Malak. Ges., 1900, pp. 49-88, pl. 1. 
Bereu, Rupoipes. Die Opisthobranchier der Sammlung Plate. Zool. Jahrb. suppl. 
This issupplemental Bd. 4, pt. 1, 1898, pp. 481-582, 8°, pl.6. (Fauna Chilensis). 
Bertin, Victor. Revision des Tellinidés du Muséum d’histoire naturelle. Nou- 
velles Archives du Muséum, ser. 2, vol. 1, 1878, pp. 203-361, pls. 8-9. 
Revision des Donacidées du Muséum d’histoire naturelle. Nouvelles Archives 
du Muséum, ser. 2, vol. 4, 1879, pp. 57-121, pls. 3, 4. 
Revision des Garidées du Muséum d’histoire naturelle. Nouvelles Archives 
du Muséum, ser. 2, vol. 3, 1880, pp. 57-129, pls. 4, 5. 
Boas, J. E. V. Spolia Atlantica, 1886, 248 pp. 4°, 8 pls. (see pp. 160-161). 
Broperir, W.J. Descriptions of some new species of Calyptreide. Trans. Zool. 
Soc. London, vol. 1, 1834, pp. 195-206, pls. 27-29. 
