THE MOLLUSCA OF PORTO RICO. 
By W. H. DALE and C. T. SIMPSON. 
INTRODUCTION. 
The following report on the mollusks of Porto Rico is the result of a study of 
collections made by the U. S. Fish Commission steamer Fish ITawk during explora- 
tions of that island in 1899, and of the antecedent literature. But little attention 
seems to have been paid to the Porto Rican marine mollusk-fauna, considered sepa- 
rately from that of the West Indies in general, and only the land shelR are at all 
well known. The principal sources of information are: (1) a paper by Shuttleworth 
on some land shells of the island; 1 (2) a monographic summary of the land and fresh- 
water shells, b 3 r Crosse; 2 (3) a similar summary of the whole mollusk-fauna, including 
the marine forms, by Gundlach; 3 4 (4) a brief paper on the land snails by von Martens.* 
The rest of the information is scattered through the literature of the West Indies 
and mollusks in general, from very earlj r times. As with the West Indian fauna in 
most branches, apart from the birds and land shells, information as to the species is 
fragmentary and unsatisfactory, no equal area of the shores of countries equally long 
known anywhere else in the world being so imperfectly explored and with the 
recorded data in such great confusion. The sea-shell fauna of the West Indies was 
the source of a large proportion of the shells known to the earliest writers, and may 
be said to rank third in the order of importance in its contributions to the early 
iconographies, coming next after the European and Indo-Pacitic regions. The 
localities were often stated erroneously or as unknown, and the same may be said of 
the great iconography of Reeve and Sowerby, based on the Cumingian collection. 
Many West Indian shells are there depicted with erroneous localities, and shells not 
known in the Antillean region are referred to it. The similarity of Spanish names 
in the Pacific, Oriental, and East American regions is no doubt partly responsible 
for this confusion. A few later lists, such as those of Beau and Fischer for Ctuada- 
loupe; Krebs and Morch for the West Indies; Guppy for Trinidad; Poulsen for St. 
Thomas; d’Orbigny, in Sagra, and Arango, for Cuba, have done something toward 
clearing up the subject, yet it is still in a deplorably unsatisfactory state. 
Some years ag'o the senior author of this report published an index to the 
periodical literature and fugitive papers on the malacology of this region, 5 6 in which 
1 Robert James Shuttleworth. Beitrage zur naheren Kenntniss der Land- und Siisswasser-Mollusken der Insel Porto 
Rico. Mitth. der Naturforschenden Gesellschaft in Bern, a. d.Jahre 1854. 8°. pp. 33-56, Marz 1854, and 89-103, Juni 1854. 
- Joseph-Charles-Hippolyte Crosse. Fauna malaeologique terrestre et fluviatile de File de Porto-Rico. Journ. de 
Conchyliologie, xi, pp. 6-71, 1892. Also issued separately in covers. 
s Don Juan Gundlaeh. Apuntes para la fauna Puerto-Riquena. Partes cuarto y quinta. Anales de la Soe. Esp. de 
Hist. Nat., xii, pp. 5-58 and 441-484, 1883. Also issued separately. 8°. 
4 Eduard von Martens. Land- und Susswasser-Sehneeken von Portorico. Jahrbueh der Deutschen malakologischen 
Uesellschaft, IV, pp. 340-367. 1877. 
6 Bulletin of the U. S. Geological Survej , No. 24. List of the marine mollusca from American localities between Cape 
Hatteras and Cape Roque, including the Bermudas. By William Healey Dali. Washington (the Survey), 1885. 336 pp. 8° 
F. C. B. 1900—23 
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