215 



ingly smalL The bioplasm has multiplied so fast that there 

 has not been time for the production even of the soft mucus. 



Vital movements resembling those which have been de- 

 scribed in the white or colourless blood corpuscles may be seen, 

 but not so easily, in the bioplasm of young epithelial cells in 

 that of cartilage, the cornea, connective tissue and other tex- 

 tures, and there can be no doubt whatever that all bioplasm 

 possesses the power of movement, and that by this is to be 

 explained the positions which the several masses respectively 

 occupy in all the different tissues which they form, and in 

 the preservation and maintenance of Avhich, in a state of 

 integrity, they play so highly important a part as long as 

 life lasts. 



Embryonic Bioplasm. — The growth and multiplication of 

 bioplasm at an early period of development may be studied 

 in an embryo, and many highly important observations may 

 be made if the tissues of the chrysalis of the common blow- 

 fly be submitted to examination, especially when they have 

 been successfully stained by the carmine fluid. A mass of 

 formless bioplasm invariably represents the earliest stage of 

 development of every tissue and organ. The bioplasm, 

 which is concerned in the formation of the special tissues, 

 emanates from this, and in many cases a sort of temporary 

 structure is formed in the first instance in Avhich the de- 

 velopment of the higher tissue afterwards takes place. If 

 one of the growling extremities of a foetal tuft of the human 

 placenta be examined, it will be found that the material Avhich 

 advances first, which grows away as it were from the tissue 

 which is already formed, is a mass of bioplasm, which is 

 dividing and subdividing into smaller portions, as repre- 

 sented in fig. 1, Plate XI. The loop of vessels gradually 

 increases in the wake of this little collection of living 

 matter which continues to move onwards as long as the 

 organ continues to grow. These little collections of bio- 

 plasm bifurcate, and thus form branches into which vas- 

 cular loops afterwards proceed. As in every other instance 

 the first changes are effected by bioplasm, and upon this 

 every kind of growth and development are entirely de- 

 pendent. 



White Blood Corpuscles, or Blood Bioplasts. — If a drop of 

 blood be obtained from the finger by pricking it with a 

 needle, alloAved to fall upon a glass slide slightly warmed, 

 covered with thin glass, carefully pressed and examined 

 under a power of 700 diameters or upwards, here and there 

 a colourless slightly granular, apparently spherical body will 

 be seen amonast multitudes of the well-known red blood- 



