1849.] Linnean Society. 63 



formed by gradual growing in of the membrane, nor could he detect 

 at this period a double membrane, which must, however, exist, to 

 admit of the subsequent separation of the contained cells. Vertical 

 septa are often formed in addition, producing a double row of cells 

 within the tube. About the time when the cells separate from each 

 other, their contents undergo a change, which exactly resembles 

 that which occurs in the contents of the parent-cells and special- 

 parent-cells of pollen when the formation of free cells is about to 

 take place in their interior. The mucilaginous matter, or protoplasm, 

 acquires a deep yellow colour, becomes much thicker, and exhibits a 

 quantity of globular bodies which look like drops of oil. Mr. Hen- 

 frey gives his reasons for regarding these appearances neither as 

 drops of oil nor as vesicular cavities, but as globular drops of the 

 yellow protoplasm^ Such globules are of various sizes and some- 

 times occupy half the cavity of the cell, but neither before nor after 

 their formation was the author enabled to detect the presence of 

 nuclei. 



Soon after the separation of these cells their yellow contents 

 exhibit lighter streaks running across, which denote that they are 

 each about to separate into four portions. When these portions are 

 completely isolated and become coated by their proper membranes, 

 they constitute the spores, and are subsequently set free by the so- 

 lution of the membrane of the parent-cells. Their contents then 

 again become clear and almost colourless, their membrane becomes 

 thickened and of a bright yellow colour, and finally their cavity 

 becomes filled with globules of pretty regular size. No trace of 

 septa dividing the parent-cells into chambers, such as are met with 

 in the special-parent- cells of the pollen, were observed, even when 

 treated with iodine ; and when the parent-cells in which the contents 

 had parted into four portions were ruptured at one place, all the 

 contents passed out and the membrane remained as a simple sac. 

 In the ripe spore the author could distinguish only a single coat, 

 which grows out into a tube at one point in germination. During 

 this process the entire spore with its contents becomes colourless, 

 the yellow colour and the globules disappearing; and after a short 

 time chlorophyll vesicles appear, which, on the application of iodine, 

 are seen to be imbedded in a coagulable, colourless protoplasm. 



In conclusion, the author again directs attention to the striking 

 circumstance, that throughout the whole course of development he 

 met with no nuclei ; neither did he observe nuclei during the deve- 

 lopment of the spores of Sphcerocarpus terrestris, which he had also 

 partially traced. Sometimes the globular bodies before alluded to 



