THE CELL THEORY, 1838 57 



that he won the attention and admiration of his chief by making a 

 complete extemporaneous report of one of Desault's lectures. Bichat 

 was a most admirable character; he has been des(Jribed as of "mid- 

 dling stature, with an agreeable face, lighted by piercing and expres- 

 sive eyes," and as being "in all relations of life most aimable, a 

 stranger to envy or other hateful passions, modest in demeanour, and 

 lively in his manners which were open and free." Two of his works, 

 his treatise on the membranes and his general anatomy are important 

 as the foundation of histology, or the minute anatomy of the tissues. 

 After the ennunciation of the cell theory Bichat's work took on a new 

 phase, namely that of microscopic study of the tissues. Schwann's 

 cell theory was in reality an extension of his work. Bichat's claim 

 for credit in connection with the cell theory has been called into ques- 

 tion inasmuch as his investigations were done without the aid of the 

 microscope. 



The Cell Theory, 1838: During the first three decades of the 

 Nineteenth century there accumulated a great mass of unconnected 

 observations on the microscopic structure of both animals and plants. 

 "We must clearly recognize," said Tyson, "the fact that for some 

 time prior to 1888 the cell had come to be quite universally recognized 

 as a constantly recurring element in vegetable and animal tissues, 

 though little importance was attached to it as an element of organiza- 

 tion, nor had its character been clearly determined." 



Eighteen hundred and thirty-eight was an epochal year in biolog- 

 ical science, chronicling as it does the ennunciation of the cell-theory 

 by Schleiden and Schwann the result of the combined efforts of 

 botanist and animal biologist. The work of Schwann, however, was 

 more comprehensive and important than that of Schleiden, and to 

 him, therefore, belongs the greater honor. 



M. Schleiden was educated for the legal profession and had engaged 

 in the practice of law. He soon abandoned it for medicine, but after 

 graduation devoted himself to the study of botany. Locy describes 

 his work in 1837, stating that he arrived at a new view in regard to 

 the origin of plant cells. This new view though founded upon er- 

 roneous observations and conclusions served to provoke discussion. 

 His work acted like a ferment, we are told, in bringing about new ac- 

 tivity. Schleiden was noted for his alertness in entering upon con- 

 troversies, a trait which better befits the lawyer than the man of 

 science whose sole concern should be the quest of truth. His replies 

 to his adversaries were at times vitriolic and he often indulged in bit- 

 ter personalities. Perhaps his legal training was responsible for this. 



His methods of investigation were sound, based as they were on 

 experiment and observation. He conceived the necessity of studying 

 the development of plants in order to understand their anatomy and 

 physiology. The nucleus of the plant cell was discovered in 1831, by 

 Robert Brown. Schleiden seized upon the nucleus as the starting 

 point of new cells but wrongly supposed that the new cells started 

 from a small clear bubble on one side of the nucleus. And yet it was 

 through these inaccurate observations of Schleiden that his co-found- 

 er, Schwann, arrived at his general conclusions. An incident is re- 

 lated of the two dining together one October evening when Schleiden 



