810 THE POPULAR SCIENCE MONTHLY. 



world the fruits of his labors and researches in a work entitled " The 

 Bee-Keeper's Handy-Book ; or, Twenty-two Years' Experience in 

 Queen-Rearing." 



Another feature of present bee-culture, which is at once both largely 

 the cause of its present advanced condition in this country and the best 

 proof of its wide extension, is its periodical literature. Devoted wholly 

 or partially to apiculture, we now have no less than three or four pa- 

 pers in Canada, and nearly a dozen in the United States. Among the 

 latter is one loeeMy devoted exclusively to bee-culture. This is the 

 " American Bee Journal," published in Chicago by Thomas G. New- 

 man. Among the former is the " Canadian Bee Journal," a weekly, 

 just commenced under the most favorable and promising auspices. It 

 is edited and published by D. A. Jones, of Beeton, Ontario. 



Since the hitherto great difficulty of successfully wintering bees in 

 these climates has been nearly overcome by the application of science, 

 bee-culture must, in the near future, become a great and profitable 

 national industry in Canada and the United States. 



■♦«»• 



STKUCTUEE AND DIVISION OF THE ORGANIC CELL. 



BtCHAELES mokkis. 



THE doctrine of the cell, as the unit of vegetable and animal 

 structure, has been constantly varying in its details since its 

 first proposal by Schleiden in 1837 and Schwamm in 1839. It was 

 at first held that the cell was a microscopic vesicle, globular in its 

 typical form, bounded by a firm membranous wall, and inclosing fluid 

 or semi-fluid contents. In its interior lay a smaller vesicle called the 

 nucleus, which occasionally held a minute mass called the nucleolus. 

 The cell-wall was believed to be its active constituent, which selected 

 materials from the surrounding fluid for cell-nutrition, and set up 

 physical and chemical changes within its contents. At a later date 

 Goodsir and Barry maintained that the nucleus was the active agent 

 in these processes, and that self-division of the nucleus was the source 

 of cell-division. It was also perceived that a cell- wall was by no means 

 always present, and Leydig defined a cell as " a little mass of soft sub- 

 stance inclosing a nucleus." A more important step of progress was 

 made about 1861, when Von Mohl, Brucke, Max Schultze, Beale, and 

 others, propounded their views upon the subject. Brucke pointed out 

 that the contents of cells frequently displayed spontaneous movement 

 and contractile power ; and Max Schultze declared that sarcode — the 

 contractile substance which forms a large part of the bodies of the 

 lower animals — was homologous with the contents of actively growing 

 cells. Von Mohl had proposed the term protoplasm to designate the 



