980 RECORD OF CURRENT RESEARCHES RELATING TO 



All four cells of the suspensor display a tendency to round off, and 

 for the dividing cell walls to split into two lamellae, so that they very 

 readily separate from one another, as also does the embryo from the 

 suspensor, being sometimes attached to it only by a common external 

 layer of mucilaginous protoplasm. 



The cell walls of the suspensor are extremely delicate, and it 

 is even doubtful whether they are composed of cellulose or any 

 isomerical substance. The entire absence of cuticularization suggests 

 the explanation oifered by Treub,* that the susj^ensory cells them- 

 selves absorb nutriment for the embryo, partly from the integuments 

 and funiculus, partly from the tissue of the placenta. The ovules of 

 the Vicie^ are, like those of other Leguminosge, campylotropous, and 

 the chalazal portion is separated from the much narrower micropylar 

 end by an elevated ridge. The long suspensor raises the embryo 

 into the micropyle, or even beyond it, which is a great advantage. 



In all the Viciete, at the time when the formation of the embryo 

 commences, the ovule aud embryo-sac are but slightly curved ; there 

 is as yet no nucellar tissue ; the inner integument is preseat, but is 

 much thinner than the outer one. The longitudinal division which 

 separates the two cells of the lower part of the suspensor from one 

 another is formed much earlier than that which divides the two 

 apical cells from one another. Sometimes, even before the latter is 

 formed, the nuclei in the two lower cells begin to divide. The two 

 nuclei thus formed lie in such a position towards one another as if a 

 transverse septum had been formed between them ; but there is never 

 the least trace of such a sej^tum. This division of the nuclei then 

 advances from the base towards the apex. Not until the nuclei in the 

 lower cells have reached a certain number, at least sixteen, do those 

 in the upper cells begin to divide ; the formation of division- walls is 

 in them also extremely rare. 



The division of the nucleus is always preceded by that of its 

 large nucleolus, which elongates, and becomes constricted into a 

 dumb-bell-like form ; the entire nucleus then assuming a long 

 ellipsoidal or fusiform shape ; but only after the nucleolus has 

 completely divided does the constriction of the nucleus itself begin. 

 While the definition of the nucleolus is always sharp, the nucleus 

 appears, during the process of division, to coalesce, at its periphery, 

 with the surrounding protoplasm. 



Gicer presents several peculiarities in the form and development 

 of the suspensor. Instead of consisting of four multinucleated, it is 

 composed of a larger number of uuinucleated cells, viz. from six to 

 nine, on the average about seven pair. Each contains a large nucleus 

 imbedded in the parietal protoplasm, and subsequently a refractive 

 spherical nucleolus. The cell-walls, though still thin, are consider- 

 ably firmer than in the other Vicieas. The number of cells, and 

 consequentlj'' of nuclei, in the suspensor of Cicer is not so large as 

 that of the nuclei in other genera, and may even be not so large as 

 that of the nuclei in a single multinucleated cell. Tlie second 

 peculiarity of the embryo of Ci'cer— whether connected or not with 

 * ' Notes sur rembryogenie de quelques Orchidees,' 1 879. 



