52o POPULAR SCIENCE MONTHLY 



remarkable and unlooked-for deviations in the larval organization and habits 

 of genera even of the same order. His inquiries respecting these animals have 

 made us acquainted with the larval forms, with relations between the larva and 

 future being; and with modes of existence, such as nature has not yet been 

 found to present in any other part of the animal kingdom. Finally with the 

 light thus derived from the study of their development, Professor Miiller has 

 subjected the organization of the entire class of Echinoderms, both recent and 

 fossil, to a thorough revision, and has added much that was new, as well a3 

 cleared up much that was obscure in regard to their economy, structure and 

 homologies. It is to their researches, which occupy seven memoirs of the Royal 

 Academy of Sciences of Berlin, that more special reference is made in the award 

 of the medal. 



It was not long after his arrival at Berlin that Miiller established 

 the Archiv fiir Anatomie und Physiologic Of this he continued the 

 publication until the time of his death. This journal, during the 

 period of its existence, formed a principal medium of publicity for 

 the labors of the leading physiologists of Germany; and the establish- 

 ment and continued superintendence of it by Miiller, in the midst of 

 other laborious employments, must be regarded as an important service 

 rendered to science. 



About this time, independent of Miiller, his pupil Schwann, fol- 

 lowing apparently in the footsteps of Schleiden, made the discovery 

 that the animal organism, just as the plant organism, was composed 

 of elementary cells. Miiller appears to have been the first to recognize 

 the great significance of this discovery. He immediately employed the 

 new fact for the explanation of certain disease phenomena and clearly 

 pointed out the agreement between tumors and pathological and em- 

 bryological development. His excellent work on the finer structure 

 of morbid tumors signifies the beginning of all microscopical investi- 

 gation in pathological anatomy, and here we see the fountain-head 

 of that stimulus which, brought to bear upon the young investigator 

 Virchow, gave rise to that well-known and comprehensive work on 

 " Cellular Pathology." 



Concerning the other events of Muller's life, during the Berlin 

 period, it takes little time to relate. The routine work in the Berlin 

 Anatomical Museum was interrupted only by the scientific expeditions 

 which the desired investigation of the sea fauna afforded. The East 

 and North Sea, Sweden, Norway, the coast of the Adriatic and Medi- 

 terranean, from Triest to Messina and Marseilles, formed the territory 

 of Muller's scientific explorations. On one of these trips, in 1855, 

 Miiller experienced a serious danger. He was returning with two 

 pupils from a journey to the coast of Norway, when at night the 

 steamer Norge on which he sailed was rammed by another and speedily 

 sank. Nearly fifty people lost their lives; and among them one of 

 Muller's young companions. In a letter to a friend in England, in 

 which Miiller gives an account of the disaster, he says that upon 

 finding himself in the water at first he kept himself up by swimming. 

 But having his clothes on, he soon became exhausted and would have 



