Author: David Starr JordanPublisher:
ISBN:
Category : Fishes
Languages : en
Pages : 684
Book Description
Check List of the Fishes and Fishlike Vertebrates of North and Middle America North of the Northern Boundary of Venezuela and Columbia
Author: David Starr JordanPublisher:
ISBN:
Category : Fishes
Languages : en
Pages : 684
Book Description
Check List of the Fishes and Fishlike Vertebrates of North and Middle America North of the Southern Boundary of Venezuela and Columbia
Author: David Starr JordanPublisher:
ISBN:
Category : Fishes
Languages : en
Pages : 690
Book Description
Check List of the Fishes and Fishlike Vertebrates of North and Middle America North of the Northern Boundary of Venezuela and Colombia
Author: David Starr JordanPublisher:
ISBN:
Category : Fishes
Languages : en
Pages : 680
Book Description
Resource Inventory of Marine and Estuarine Fishes of the West Coast and Alaska
Author: Nekton
Author: Yu.G. AleyevPublisher: Springer Science & Business Media
ISBN: 9401013241
Category : Science
Languages : en
Pages : 430
Book Description
1. Nekton as an ecomorphological type of biont The term nekton was suggested and used for the first time in 1890 by E. Haeckel in his book Plankton-Studien. Etymologically the word nekton derives from the Greek VTJKTTJP, i.e. swimming. As Haeckel defined it, nekton describes collectively all swimming animals that are 'free to choose their path', i.e. can resist a strong current of water and, distinct from planktonic animals, go where they wish. While giving a general idea of the dividing line between plankton and nekton, Haeckel's definition, which has played an important role in shaping our ideas about nekton, today no longer provides a sufficient basis for ecological and functional morphological investigations, since it affords no possibility of quantitatively assessing either the boundary between plankton and nekton or that between nekton and other ecomorphological types of biont. Thus Parin (1968), proceeding from Haeckel's principle, believes that in the epipelagic zone of the ocean the minimum size of nektonic fishes with a well-developed capacity for active swimming may be between 15 and 30 cm, as fishes shorter than 15 cm are unable to counter oceanic currents. Meanwhile young Leucaspius (Leucaspius delineatus) only 1.5 cm long, observed by this writer in ponds near Moscow proved capable of active horizontal migrations across the entire body of water, which, if Haeckel's definition is accepted, brings the border between planktonic and nektonic fish in this case to between 1.5 and 2.0 cm.
Lewis and Clark
Author: Paul Russell CutrightPublisher: U of Nebraska Press
ISBN: 9780803264342
Category : History
Languages : en
Pages : 550
Book Description
First published in 1969, Lewis and Clark: Pioneering Naturalists remains the most comprehensive account of the scientific studies carried out by Meriwether Lewis and William Clark during their overland expedition to the Pacific Northwest and back in 1804?6. Summaries of the animals, plants, topographical features, and Indian tribes encountered are included at the end of each chapter devoted to the particular leg of the journey. A distinguished biologist, Paul Russell Cutright will be remembered for this landmark contribution to our understanding of the world that the expedition observed and recorded.
Report of the Commissioner for ...
Author: United States Fish CommissionPublisher:
ISBN:
Category : Fisheries
Languages : en
Pages : 684
Book Description
Bulletin
Author: Translation Series
Author: List of Publications of the Department of Commerce Available for Distribution
Author: United States. Dept. of CommercePublisher:
ISBN:
Category :
Languages : en
Pages : 164
Book Description