PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 3d9 
It is apparently a salt-water mollusk, and varies from pure white to 
dark purple, with, in general, little or no epidermis. 
s 
Cyrena carolinensis Lam. 
Numerous rather small specimens, all dead, were obtained in the 
“salt ponds” at Key West. They appear to be uniformly purplish. 
PARASTARTE Conrad. 
Parastarte Conrad. Proceedings Acad. Nat. Sci. Philadelphia, June, 1862, p. 
2x8. 
Callicistronia Dall, MS. Science ii, p. 447, Sept. 28, 1883. 
Shell porcellanous, thick; with color markings; covered with a glisten 
ing dense Vernicose epidermis ; without lunule or eseutchbeon; liga- 
ment stout, very short, wholly external, nearly central, but placed a lit- 
tle more to the same side of the beaks as the pallial sinus, that is to 
say, posterior; almost covered by the umbones; margin crenulated ; 
muscular impressions large, strong, subequal; pallial line with a small 
rounded sinus; hinge with one simple large ungrooved triangular 
tooth in the right valve under the subcentral umbo; the posterior 
margin of the shell obsoletely grooved; left valve with two stout di- 
varicating simple teeth, with a triangular space between them ; an ob- 
solete groove on the anterior shell margin ; soft parts unknown; animal 
viviparous. 
I am indebted to Mr. Tryon for informing me of Conrad’s description 
which I had overlooked, as it is in the midst of irrelevant matters and 
1 believe has never been noticed by any other author. His diagnosis 
contains no differential characters, and he seems to have overlooked 
altogether some of the most important. He was afterwards, according 
to Mr. Tryon’s note, disposed to unite it with Goodallia of Turton, which 
it resembles in a general way; but that shell appears not to differ from 
Astarte ; has an entire pallial line; the large triangular tooth is gen- 
eraily grooved, though sometimes very faintly; the ligament is long as 
in Astarte, and there is a distinct lunule. With regard to its reprodue- 
tion nothing is known.* Gooda/lia dates from 1822, and Jlactrina 
Brown is synonymous with it. 
Parastarte triquetra Conrad, (Pl. X Figs. 1-3.) 
Astarte triquetra Conrad, Proc. Acad. Nat. Sciences Philadelphia, vol. iii, 
p. 24, pl. 1, fig. 6, 1846. 
This little shell was very briefly described by Mr. Conrad. It is of 
a yellowish color, with a purple stain inside in many specimens, which 
is visible outside as a purple ray which includes and is strongest on 
the beaks; the epidermis is straw-colored and of most brilliant polish ; 
the form of the shell subtriangular, becoming ventrally elongatec with 
*After examination of many specimens of the type of Goodallia I have heen able to 
find nothing but eggs. These were few in number in each specimen, and dispropor- 
tionately large. The genus is probably oviparous. 
