254 THE PHENOMENON OF 



age, and, according to the researches of an anonymous* 

 author, sprout forth as little utricular protrusions from 

 the cells of the surrounding tissue, and penetrate through 

 the thin-walled canals of the dots into the vessels. In 

 these thy 11s, which appear quite as true, partial, and local 

 Rejuvenescences of the cells, nuclei are formed at a time 

 when those of the mother-cell have long since vanished, 

 never becoming renovated. 



2. Shutting-off of a daughter-cell in the domain of 

 fructification. The shut-off and detached daughter-cell 

 becomes a spore, while the mother-cell remains vegetative. 

 This case doubtless occurs in the spore-formation of many 

 Fungi, particularly the true Hymenomycetes,f many 

 Gasteromycetes, \ and most Hyphomycetes. 



The multiplication of the cells in the Algal genus 

 'Exococcus (Nageli, 'Algensyst,' 169) and the fermentation 

 Fungi, I also takes place by the shutting off, and fre- 

 quently complete tying-off (Abschniirung) of either 

 terminal or laterally budding daughter-cells. But as all 

 the cells are of like character here, these cases would be 

 more properly referred to the domain of vegetative cell- 

 formation. 



c. RECONSTRUCTION, WITH DIVISION INTO FOUR 

 DAUGHTER-CELLS. From the pregnant discoveries of Ad. 

 Brongniart^[ and H. v. Mohl,** on the formation of the 



* ' Untersuch. iib. die Zellenartig. Ausfullung. der Gefasse,' (' Bot. Zeit., 5 

 1845, pp. 225, 241, t. ii.) 



f See Phoebus, ' Ub. der Keimkornerapparat. der Agariceu,' &c., ' Nov. 

 Act. Nat. Cur.,' xix, 11, (1842,) p. 171, t. 56, 57. Corda, 'Ic. Fung.,' iii, 

 t. 79 ; iv, t. 10, figs. 1341 39 ; v, 1. 10. 



J See Tulasne, ' De la Fructification des Scleroderma comparee a celle des 

 Lycoperdon et Jlovisla,' 'Ann. des Sc. nat.,' 17, (1842,) p. 5, t. 1, 2, 'Sur 

 les Genres Polysaccum et Geaster,' ibid. 18, (1842,) p. 129, t. 6. 



See Schleiden, 'Grundz.,' ii, pp. 38, 39, figs. 106, 107, ('Principles,' 

 pp. 153, 154, figs. 122, 123; Corda, 'Ic. Fung.,' ii. t. 10, fig. 68, (Ferti- 

 cillium;) iii, t. 1, fig. 23, (Botryiis) ; iv, t. 10, fig. 132 (Isuria). 



|| See Saccharomyces Ceremsia, in Meyen, 'Pflanzen-physiol.,' iii, p. 455, 

 t. x, f. 22. 



^| ' Sur la Generation et le Developpement de PEmbryon,' ' Ann. des Sc. 

 nat.,' 1827. 



** ' Ueb. der Bau tmd die Form der Pollenkorner,' (1834) ; Ub. die 

 Eutwicklung und den Bau der Sporen der Kryptogamische Gewachse,' 

 ('Flora,' 1833,) 'Vermischte Schriften,' p. 67. 



