224 



The first work was, accordingly, to eut the anther, drawn 

 in fig. VII, in a great number of transverse slices and to 

 examine if the brown corpuscles consisted of ovules. This 

 first opération was a failure, the paraffine not having 

 penetrated in a sufflcient degree and consequently the 

 préparation lacking distinctness. In order to be quite sure 

 a second time, the anther, represented in fig. III, remained 

 immersed in absolute alcohol for three days, then in 

 turpentine, next for several days in a fluid mixture of 

 turpentine and paraffine and finally during twenty hours 

 in paraffine of 60° C. After this the anther was enclosed 

 and eut into a long séries of thin sliees without any 

 difficulty. Three of thèse slices are represented in fig. VIII, 

 a, b and e. In the first the filament is to be seen without 

 any connection with the anther-cells, in b a slight con- 

 nection is visible, whereas in c the connective holds the 

 two thecae together. 



The lines a, b and c in fig. III indicate the relative pla- 

 ces of the sliees. 



The principal feature of this and the other sections, 

 either higher or lower, is that they show a kind of pla- 

 centa growing forth out of the tissue ') towards which — 

 before the dehiscence — the valves of the anthers curve. 

 Thèse placentas hâve the greatest development at the 

 base of the anther and gradually decrease in the direction 

 of the top where they are reduced to the normal dimen- 

 sions of the said tissue. As soon as the placentas, to 

 which the connective sends out a spécial set ofsmall cells, 

 hâve assumed certain proportion, they commence producing 

 ovules, which according to our figures instead of being 

 anatropous, seem to be not quite normal. 



1) Turpin called this tissue at the time //trophopollen" holding 

 that it was the producer of pollen (H. von M o h 1, Verm. Schr. 

 bot. Inh. p. 31). 



