William Healey Dall, (August 21, 1845 - March 27, 1927), was a great American naturalist and a prominent malacologist. He described many mollusks of the Pacific Northwest of America. He would become America's preeminent authority on living and fossil mollusks.

But he also made substantial contributions to ornithology, vertebrate and invertebrate zoology, physical and cultural anthropology, oceanography and paleontology. He also performed meteorological observations in Alaska for the Smithsonian Institution.

Biography

Dall was born in Boston, Massachusetts. His father Charles Henry Appleton Dall, (1816-86), a Unitarian minister, moved in 1855 to India as a missionary. His family however stayed in Massachusetts, where Dall's mother Caroline Wells Healey was a teacher.

In 1862, Dall’s father, on one of his few brief visits home, brought his son in contact with some naturalists at Harvard, where he had studied, and in 1863, when Dall graduated from high school, he took a keen interest in mollusks.

In 1863 he became a pupil of Louis Agassiz of Harvard's Museum of Comparative Zoology, in natural science. He encouraged Dall's interest in malacology, a field still in its infancy. He also studied anatomy and medicine under Jeffries Wyman and Dr. Daniel Brainerd.

Dall took a job in Chicago. There he met the famous naturalist Robert Kennicott (1835-1866) at the Chicago Academy of Sciences Museum.

In 1865 the Western Union Telegraph Expedition was mounted to find a possible route for a telegraph line between North America and Russia by way of the Bering Sea. Kennicott was selected as the scientist for this expedition, and with the influence of Spencer Fullerton Baird of the Smithsonian Institution, he took Dall as his assistant, because of his expertise in invertebrates and fish.

Aboard the schooner Nightingale, under the command of the whaler and naturalist Charles Melville Scammon (1825-1911), Dall explored the coast of Siberia, with first several stops in Alaska (still Russian territory at that time). Scammon Bay, Alaska was named after Charles Scammon.

In 1866, Dall continued this expedition to Siberia. On a stop at St. Michael (Alaska), he was informed that Kennicott had died of a heart attack on May 13, 1866, while prospecting a possible telegraph route along the Yukon River. Set on finishing Kennicott's Yukon River work, Dall stayed on the Yukon during the winter. Because of cancellation of his own expedition, he had to continue this work at his own expense until autumn 1868.

Meanwhile, in 1867, the U.S. had acquired Alaska from Russia for 7.2 million dollars. This was an unchartered country, with a fauna and flora still waiting to be explored and described, a task Dall took upon him as a surveyor-scientist.

Back at the Smithsonian in Washington, he started cataloguing the thousands of specimens he had collected during this expedition. In 1870 he published his account of his pioneering travels in Alaska and Its Resources, describing the Yukon Territory, the geography and resources of Alaska, and its inhabitants.

In 1870 Dall was appointed Acting Assistant to the U.S. Coast Survey (later renamed the U.S. Coast and Geodetic Survey in 1878).

He went again on several reconnaissance and survey missions to Alaska between 1871 and 1874. His official mission was to survey the Alaska coast, but he took the opportunity to acquire specimens, which he collected in great numbers.

1871-72 : He surveyed the Aleutian Islands.

In 1874 aboard the Coast and Geodetic Survey schooner Yukon, he anchored in Lituya Bay, which he compared to Yosemite Valley (California), had it retained its glaciers.

He sent his collection of mollusks, echinoderms, and fossils to Louis Agassiz at Harvard's Museum of Comparative Zoology; plants went to Asa Gray at Harvard; archaeological and ethnological material went to the Smithsonian.

In 1877 he published his book Tribes of the Extreme Northwest.

In 1877-1878 he conducted “the Blake Expeditions”, mounted by Major G.M. Blake, along the East Coast of the US. The major publications on the Blake Expeditions were published in the Bulletin of the Museum of Comparative Zoology Harvard :

• Dall, W.H. 1885-1886, Vol. XII, Report on the Mollusca, Part I Bivalvia
• Dall, W.H. June 1889, Vol. XVIII, XXIX – Report on the Mollusca, Part II Gastropoda & Scaphopoda

In 1879 he explored again Alaska’s scenery in the company of, among others, the famous John Muir (1838-1914). Dall saw white sheep roaming on Mount McKinley. They would later be called Dall's sheep (Ovis dalli, Nelson 1884). He published his findings in : Meteorology and Bibliography of Alaska.

He was in Europe in August 1878, sent to a meeting in Dublin of the British Association for the Advancement of Science. He took the opportunity to visit mollusk collections and meet European scholars.

Dall married Annette Whitney in 1880. Their honeymoon went to Alaska. Arrived in Sitka, his wife went back home to Washington, D.C. He began his final survey season aboard the schooner Yukon. He was accompanied, among others, by the ichthyologist Tarleton Hoffman Bean (1846-1916).

In 1882 he published The Currents and Temperatures of Baring Sea and the Adjacent Waters and in 1883 Alaska Coast Pilot .

In 1884, Dall left the U.S. Coast and Geodetic Survey, having already written over 400 papers. In 1885 he transferred to the newly created U.S. Geological Survey, obtaining a position as paleontologist. He was assigned to the U.S. National Museum as honorary curator of invertebrate paleontology, studying recent and fossil mollusks. He would hold this position until his death. In the same year, he published List of Marine Mollusca.

As part of his work for the U.S. Geological Survey, Dall made trips to study geology and fossils: northwest (1890, 1892, 1895, 1897, 1901, and 1910), Florida (1891), and Georgia (1893).

In the following years he published : Report on the Mollusca Brachiopoda and Pelecypoda of the Blake Expedition (1886); Mollusca of the Southeast Coast of the United States (1890); Instructions for Collecting Mollusks (1892); Contributions to the Tertiary Fauna of Florida (4 vols., 1890-98); Neocene of North America (1892); Coal and Lignite of Alaska (1896).

In 1899 he and an elite crew of scientists, such as the expert in glaciology John Muir, were members of the Harriman Alaska Expedition, aboard the S.S. George W. Elder, along the glacial fjords of the Alaska Coast, the Aleutian Islands and to the Bering Strait. Many new genera and species were described. He was the undisputed expert on Alaska, and the scientists aboard were often surprised by his erudition, both in biology and in respect to the cultures of Alaskan people.

He spent two months at the Bishop Museum in Hawaii examining their shell collection.

His contributions to the reports of the Harriman Alaska Expedition, include a chapter Description and Exploration of Alaska, and Volume 13, Land and Fresh-water Mollusks.

He was elected member of most of the U.S. scientific societies, vice-president of A.A.A.S. (1882, 1885), National Geographic Society, Philosophical Society of Washington. In 1897 he was elected to the National Academy of Sciences. His eminence earned him also several honorary degrees.

Publications

He published over 1,600 papers, reviews, and commentaries; describing 5,302 species, many of them mollusks. Many of these papers were short. He described some of his species with a few short sentences, such as “It is a small white snail, living in Alaska”, accompanied by a drawing. A following description might then be "It is a white, small snail from Alaska" accompanied with another drawing. Descriptions, such as these, are essentially useless. On the other hand, other papers were comprehensive monographs.

Species named after him

Mollusks:

• Dallina Beecher, 1895
• Dalliella Cossman, 1895
• Notoplax dalli Is. & Iw. Taki, 1929
• Hanleya dalli Kaas, 1957.

Mammals:

• Dall's sheep (Ovis dalli) Nelson, 1884
• Dall’s Porpoise (Phocoenoides dalli, F. True 1885)

Reference

• Lindberg, D.R. : William Healy Dall : A Neo-Lamarckian view of molluscan evolution. The Veliger 41(3):227-238.

External links

• The Harriman Expedition, 1899
• Dall’s Sheep