452 Mr. A. Henfrey on the Reproduction of the 



the proembryo becoming much elongated, drive the point of the 

 proembryo deep into the substance of the nucleus (E. fig. 10, 11), 

 which at this time becomes lax and half-dissolved. The longi- 

 tudinal series of cells, of which each proembryo presents four, 

 now become isolated into filaments [suspensors) (E. fig. 12, 13), 

 and the cell at the lower extremity of each suspensor becomes 

 divided repeatedly to form an embryo (E. fig. 13^), so that at 

 this time there are four times as many rudimentary embryos as 

 there are corptiscles *. Out of all these only one becomes fully 

 developed ; the rest are arrested and displaced by the growth of 

 that one which forms the embryo of the ripe seed. 



Before leaving the subject, we may advert to the idea lately 

 propounded by Geleznofi*, from his researches on the Larch, that 

 the embryo is formed from a cellule which originates in the end 

 of the pollen-tube and passes through an orifice into the cor- 

 puscle. This idea may easily have arisen from imperfect obser- 

 vation, and cannot be readily connected with anything observed 

 by other authors. 



Review of the Phenomena of Reproduction in the 

 ^^-^ {' Flowerless and Flowering Cormophytes. 



Th( 



16 discoveries which have been made within the last few 

 years seem to leave little doubt of the existence of sexuality, 

 down to the lowest of the Cormophytes, even if we refuse to ad- 

 mit the evidence of its probable extension to the Thallophytes, 

 and so throughout the vegetable kingdom. 



It is impossible moreover to mistake the striking connexion 

 between the various forms of the reproductive structures which 

 present themselves in the difierent groups ; and it may be worth 

 while to examine this point briefly here. 



In the Angiospermous flowering plants, we find the perfect 

 plant producing pollen and ovules in distinct organs : the pollen 

 falling upon the stigma developes tubular prolongations which 

 pass down into the ovary and enter the ovules, where they come 

 in contact with the embryo-sac, and thus fertilize an embryonal 

 vesicle existing in the interior of that sac (a greater or less quan- 

 tity of endospermous cells also exists there). This then under- 

 goes subdivision into two cells, and while the upper of the pair 

 of cells thus formed is developed more or less into a confer void 

 filament, called the suspensor, the lower cell becomes developed 

 into the embryo (mostly causing the absorption of the endo- 

 sperm), which acquires its distinct form with one or more coty- 

 ledons, and a radicle, before it is cast off from the parent. We 



* This resembles the process in Mosses when the spore produces a con- 

 fervoid body, from which a number of stems bud out. 



