NO. 1704. A rOLLECTIOX OF fiHELLl^ FROM PERV—DALL. 185 



Tryon, George Washington (and Pilsbry, Henry Augustus). Manual of 

 Conchology, structural and systematic. 17 vols., 8", 1879-1898. (Man. Con.) 



After the death of Mr. Tryon, in 1888, this work was continued by Doctor Pilsbry. 

 The above title refers to the series containing the Marine Gastropods only. In par- 

 ticular monographs the authors were assisted by W. B. Marshall, Benjamin Sharp, 

 and S. Raymond Roberts. 

 WissEL, Kurt von. Beitrage zur Anatomic der Gattung Oncidielhi. Zool. Jahr- 



buch, suppl. Bd. 4, pt. 1, 1898, pp. 583-640. 

 Zoological Society of London. Proceedings, 1832-1854. 8°. 



Includes descriptions of species collected on the west coast of South America by 

 Hugh Cuming, and diagnosed by Broderip, Sowerby, Powys, Swainson, and others. 

 These descriptions as a rule have no titles assigned to them. (Proc. Zool. Soc.) 



THE PERUVIAN PROVINCE. 



The littoral marine molluscan faunas of the west coast of the two 

 Americas, excliidino; the Arctic and Antarctic faunas properly so 

 called, were recognized more than half a centurj" ago in their main 

 outlines by Woodward.^ 



They comprise, beginning at the north: 



1. The Oregonian Province, extending from the limit of floating ice 



in Bering Sea south to Point Conception, California; 



2. The Californian Province, ranging from Point Conception south 



to Lower California ; 



3. The Panamic Province, from Lower California, including the Gulf 



of California, south to the Bay of Guayaquil, Ecuador; 



4. The Peruvian Province, extending from Guayaquil south to the 



vicinity of the island of Chiloe in southern Chile ; and 



5. The Magellanic Province, from Chiloe to the Fuegian Archipelago, 



and for a short but undetermined distance north on the Argen- 

 tine coast, on the Atlantic side. 



These provinces will eventually be recognized as containing minor 

 divisions, with which, on this occasion, we are not concerned. 



The distribution recognized in the term "Province" appears to 

 be directly dependent on the temperature of the surface stratum of 

 the sea which, in its turn, is distributed by ocean currents. In the 

 case of the Peruvian Province a branch of the eastward-flowing 

 south Pacific current diverges from the main stream and impinges 

 upon the coast of South America in the vicinity of Chiloe Island. 

 Thence it follows the coast northward, until by the northwesterly 

 trend of the Peruvian shores it is diverted, in the vicinity of Point 

 Aguja and Cape Blanco, to the westward, where it continues in the 

 direction of the Galapagos group of islands. This current, known as 

 the "Peruvian" or "Humboldt" current, throughout its entire extent 

 maintains a temperature varying with the season of from 65° to 70° 

 F. The temperature of the surface off Aguja Point, Peru, in Novem- 

 ber was 65° F. The temperature of the water in the Magellanic 



a Manual of the MoUusca, 1856, pp. 373-377. 



