THE NAUTILUS. 11 
imens of both species from several localities in the West Indies, and 
the characters described in the books do not hold good to separate 
them. It is a pity that some naturalist has not examined the 
animals. 
It is also doubtful if C. exusta Sowerby, and C. talpa, Linn, are 
distinct. I have a specimen of the typical C. exusta from Mr. 
Sowerby, and another which I received from Mr. Damon, of Wey- 
mouth, England, seems to me to connect the two species. Weinkauff 
may be right in making C. exusta a variety of C. talpa. 
The opinion held by some that C. decipiens Smith, was a dwarf 
variety of C. thersites Gaskoin, has been definitely set at rest by Mr. 
Sowerby receiving last summer, a number of fine specimens of C. 
decipiens from Australia. I was fortunate enough to obtain one of 
them—probably the first specimen that has none America. It is 
certainly a good species, and one of the most beautiful of all the 
Cypreas. The palm of beauty probably lies between it and C. 
aurantium Martyn. By the way, the fabulous prices given for the 
last-named shell are things of the past. Instead of costing anywhere 
from $50 to $100, a ood specimen can be obtained for $15, and the 
finest kind of one for $20 to $22. It is no longer a rare species, but 
can readily be obtained from any of the prominent shell-dealers of 
Europe. 
Philadelphia, April 10, 1889. 
THE SHELL-BEARING MOLLUSCA OF RHODE ISLAND. 
BY FORUGE Dew ae. 
Chapter inv. 
SUB-ORDER INTEGRIPALLIATA. 
Siphons short, not retractile ; pallial impression simple, without 
sinus. This sub- order, contains fifteen families. 
FAMILY CYRENID 4. 
Shell regular, oval or sub-trigonal, covered with an epidermis ; 
hinge with two or three teeth in each valve ; lateral teeth, two, simple 
or striated ; ligament external ; pallial impression simple, or with a 
short sinus 
This family has been made the special study of Mr. Temple Prime, 
a lawyer of N. Y. City, who is authority on this subject. He pub- 
lished, in 1865, a monograph of the species inhabiting the American 
Continent, illustrated with figures and giving all “the synonyms, 
localities and other items of interest concerning them. In 1871 he 
published a catalogue of all the species in the world (of this family), 
known to date. He divided it into six genera and three hundred 
and twenty-two species, of which one hundred and eleven are Amer- 
ican. There are now recognized seven genera and nearly four hun- 
