50 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



link, and therefore no affinity. We have merely two parallel 

 series, of which the results are, to some extent, the same. A 

 great advance has certainly been made in the Cryptogam ; a true 

 embryo has been formed ; there is, to use a German phrase, a 

 greater differentiation of parts ; but, after all, there is a wide 

 and impassable gulf, between the two, and in the absence of all 

 evidence of a bridge passing over the gulf, it seems to me 

 unphilosophical to allow any close affinity. 



37. It has sometimes been urged that there is a prothallus in 

 Conifers which brings them near to Club-mosses. If there is 

 any prothallus it is the endosperm, and that certainly has the 

 same functions and the same signification in Conifers as in 

 other plants, though it may be more completely developed 

 before the formation of the embryo than elsewhere. The 

 suspensors in other Phcenogams are possibly the same organs 

 with the corpuscles of Conifers, or, at least, analogous with' 

 them.* 



38. But it may be well to look to one or two more points in 

 Conifers as regards comparative dignity. The slow develop- 

 ment of the fructifying organs, and the curious phenomena in 

 the pollen grains preceding the protrusion of the pollen tubes, 

 seem to be proofs of superior dignity. The highest recent 

 Cryptogams are doubtless the Club-mosses, in which the 

 process is extremely slow; the moulds, on the contrary, fruit 

 and reproduce their species within a few days. In respect 

 to the naked ovules, there is little difference between im- 

 pregnation by means of a stigmatic tissue and immediate 

 impregnation through the micropyle. There is precisely 

 the same process in both when once the pollen reaches 

 the micropyle. The only difference is in the preliminary 

 act. It is not, perhaps, quite so clear that impregnation 

 may not take place sometimes without the intervention of 

 a stigma, even in plants which possess that organ. Pollen 

 grains must sometimes fall upon the micropyle of the naked 

 ovules of Reseda, and as they may be made to germinatef 



* If these suspensors are deduplieations of the embryo-sac, the cor- 

 respondence of the corpuscles and archegonia is far less strikinf. 

 t Reissek Act. Nov. vol. xxi. P. 2, p. 469. 



