284 H0FME1STER, ON 



four globular daughter-nuclei; there may also be found 

 sets of four tetrahedral daughter- cells, individual daughter- 

 cells, of a globular form, and lastly, others which already 

 exhibit the transparent halo slightly developed. The ap- 

 pearance of the latter is not accompanied by any percepti- 

 ble contraction of the contents of the globular cell. If the 

 cells which, when treated with water, exhibit the above- 

 mentioned halo, are examined in the fluid contents of the 

 sporangium, their membrane appears thin and quite homo- 

 geneous even under the best microscopes. But in sporangia 

 a little more advanced, the membrane in question under 

 similar circumstances appears to be composed of two layers, 

 the inner one of which is thicker and more highly re- 

 fractive than the outer one. The outer layer, when treated 

 with alcohol, contracts so as to be hardly distinguishable 

 from the inner one. At the same time the cell-contents con- 

 tract, sometimes into a globular shape, sometimes irre- 

 gularly. If water is applied the outer layer swells con- 

 siderably, and forms a thick, gelatinous, almost fluid cover- 

 ing, round the inner one, which remains unaltered. Under 

 the further action of water this gelatinous layer is dissipated 

 in the surrounding fluids. The effect of alcohol upon the 

 fresh cell is to lessen considerably this power of distension. 

 After treatment with alcohol the outer layer only swells up 

 to a definite extent (to about three times its original size), 

 in distilled water. If the preparation is now crushed, the 

 swollen layer is pressed out over a wide space, and is then 

 clearly seen to consist entirely of a homogeneous hyaline 

 gelatinous substance, and that the granular aspect of its 

 outer surface is owing to the attachment of small extrane- 

 ous bodies. A longer exposure to the effect of alcohol 

 often entirely destroys the capacity for distension. 



Iodized solution of chloride of zinc imparts a pale blue 

 colour to the entire mass of the outer membrane, and 

 renders the inner one yellow. After the cells have lain in 

 alcohol the same solution renders the outer layer pale yellow, 

 and the inner one brown. The addition of water brings 

 out the blue colouring in the outer layer. Ammoniated 

 oxide of copper applied to the fresh cell causes only a slight 

 distension of the outer layer, and hardens it so that it no 



