SUMMARY OF RESULTS. 
77 
to the surface of the water. The starfish had been entangled in the line so little above 
the mud, that fragments of its arms, which had been broken off in the ascent of the 
line, w T ere picked out from amongst the mud.” 1 
In 1826 Henry Milne-Edwards and Audouin made zoological expeditions along the Milne-Edwards, 
French coasts, afterwards continued on the Sicilian coasts with de Quatrefages ; in Lotke > Darwin. 
1828 the Russian Liitke explored the archipelago of the Caroline Islands, and from 
1831 to 1836 the observations of Fitzroy and Darwin w r ere conducted during the voyage 
of the “Beagle.” These expeditions awakened much interest in marine zoology, and 
gave an impetus to many scientific questions connected with oceanography. 
In 1836 Ehrenberg produced his first works. His name will ever remain inseparably Ehrehberg’s 
connected with the discoveries relating to the microscopic organisms of the sea. It would Studies^ 1 ° 
be impossible to enumerate here the numerous memoirs and important publications of this 
mierographer, who devoted his whole life, with extraordinary activity, to the study of 
microscopic organisms, of atmospheric dust, of material brought up from deep sound- 
ings, and of numerous questions appertaining to the sea. One salient point may be 
dwelt on, viz., the connection he established between certain classes of living microscopic 
organisms and the part they played in geological times. As early as 1836 he showed 
that the siliceous strata known as “ Tripoli,” found in various parts of the globe, especi- 
ally at Bilin in Bohemia, were but an accumulation of the skeletons of Diatoms', Sponges, 
and Radiolaria ; he pointed out the presence of Diatoms in the subsoil of Berlin. In 
1839 his observations at Cuxhaven revealed the presence of living Diatoms and Radio- 
larians on the surface of the Baltic, belonging to the same species as those found fossil in 
the Tertiary deposits of Sicily and Oran. He showed, moreover, that in the Diatom 
layers of Bilin the siliceous deposit had, under the influence of infiltrated water, been 
transformed into compact opaline masses. Starting from these facts, he concluded that 
rocks similar to those which play so important a part in the terrestrial crust are still 
being formed on the bottom of the sea by minute organisms. He recognised the association 
of greensand and Globigerina limestone. His observations exercised a great influence on 
the study of micro-organisms, whose role in nature is in an inverse ratio to their size. 
The United States sent out their first purely scientific expedition in 1839 under the Wilkes’ 
command of Captain Wilkes. This expedition returned in 1842; its work was chiefly XPED1TI0N * 
geographical and astronomical, but during the first year a few dredgings were made 
in shallow water, and a number of deep soundings were obtained at intervals during the 
voyage. The sounding line employed was a copper wire, a great improvement on 
previous methods. The great American naturalist Dana, who accompanied this ex- 
pedition, added much to our knowledge of several groups of shallow-water and pelagic 
animals, and the geology and mineralogy of many oceanic islands. 
1 See Carpenter, Proc. Roy. Soc., vol. xvii. p. 177, 1868. 
