84 THE NAUTILUS. 



Note on Antillean Paleogeography. A recent paper by A. P. 

 Brown and the writer, describing the freshwater shells of the 

 Oligocene of Antigua (Proc. A. N. S. Phil., 1914, p. 309) 

 seems to throw some light upon the little-understood paleogeo- 

 graphy of the West Indies. The presence of three species of 

 Hemisinus indicates that although a large area of the present 

 Antillean islands was submerged in the Oligocene, there must 

 have been considerable extent of land, since these are river 

 snails, and a number of species would not be likely to have been 

 evolved, or to exist, unless permanent streams existed at least 

 equal to those of the larger Antillean islands. The Oligocene 

 fossil Ectracheliza truncata Gabb, from Santo Domingo, further 

 supports this view. This shell is not marine, as Gabb supposed. 

 It is really nothing but a Hemisinus, though a very large one, 

 equal to the large South American species. It may be regarded 

 as certain that at the stage of the Oligocene when the Antigua 

 bed was formed, as well as those of Santo Domingo, a considerable 

 land area existed in the eastern Antillean region, and that this 

 land was, or had been, connected with continental South Amer- 

 ica, the original home of Hemisinus. The marine fossiliferous 

 beds of northern Santo Domingo and of Haiti, as well as that 

 of Bowden, Jamaica, were deposited in shallow water near the 

 shore, judging from the character of the fossils. 



H. A. PlLSBRY. 



PUBLICATIONS RECEIVED. 



Littoral Marine MoUus&s of Chincoteague Island, Virginia. By 

 John B. Henderson and Paul Bartsch. Proc. U.S.N.M., Vol. 

 47, pp. 411-421, plates 13, 14. New species are Epitonium vir- 

 ginicum, Turbonilla powhatani, T. pocahontasa, T. toyatani, T. 

 virginica, Odostomia toyatani, 0. virginica, 0. pocahontasa, Tri- 

 phoris pyrrha, Diastoma virginica, Cerithiopsis virginica. The 

 large, typical form of Urosalpinx cinereus was found, up to 

 51.5 mm. long. In a protected cove, in which cold springs keep 

 the bottom temperature down to about 8 below that of the open 

 sea, the northern species Yoldia Umatala and Nucula proxima 

 were found. H. A. P. 



