THE HIGHER CRYPTOGAMIA. 81 



germinal vesicle into the fruit the slowest. After the 

 completion of the rudiments of the fruit-sac, the calyptra 

 has only increased moderately in size, and the impregnated 

 germinal vesicle is still undivided, although doubled in 

 length. In the fruit-sac, when from I to 3 mm. long, the 

 rudimentary fruit is only 4-8 cellular (PI. X, fig. 8). At 

 all stages of development it entirely fills the cavity of the 

 calyptra. The condition figured by Gottsche is certainly a 

 diseased one ; the rudimentary fruit, developing itself feebly, 

 could not follow the growth of the walls of the archegonium. 



In certain Muscineae {Pellia epiphylla, Jung, divaricata, 

 Phascum cuspidatum), and also in some vascular cryptogams 

 {Pteris aquilina, Aspidium Filix-mas, and Salvinia nutans), 

 where several archegonia of one and the same group have 

 been impregnated, the less developed of these archegonia 

 have afforded me similar cases decisive of the point that 

 the increase in size, and the form of the growing base of 

 the archegonium, is not produced by the contact of the 

 rudimentary fruit or of the embryo. In all these cases, 

 moreover, two archegonia of the same prothallium had been 

 impregnated ; the arrest of development of the embryo had 

 occurred in the less-perfect archegonium, which had 

 manifestly been the latest impregnated and insufficiently 

 nourished. 



In the leafy as well as in the leafless Jungermanniae the 

 individualization of the elaters and spore-mother-cells is 

 preceded by a considerable thickening of their walls, and 

 the conversion of the substance of these walls into a mate- 

 rial which swells up extensively in water. The mass of the 

 thickened cell-walls often swells up in water more rapidly 

 and to a greater extent than even in Pellia ; in J. bicuspidata, 

 Badula complanata, and Frullania dilatata, the determina- 

 tion of the arrangement of the cells of the interior of the 

 young capsule is thereby rendered extremely difficult. In 

 all the species which I have examined the substance of the 

 walls, when moistened with tincture of iodine, became 

 quite blue. In the mother-cells of the large-spored Frulla- 

 nia dilatata four protrusions of the wall (quite similar 

 to those of Pellia, before mentioned,) and the gradual 

 increase in size of the inner wall of the superimposed 



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