266 Professor Henslow's Examination 



the prosecution of these enquiries. There were three or four 

 plants of lutea in my garden which were quite deficient in 

 pollen, and which nevertheless produced perfect seeds. I was 

 unable to detect even a single grain of pollen either healthy 

 or abortive in their anthers, though these latter organs appeared 

 to be well formed and perfected. The ovaria of these plants 

 indeed contained plenty of ovules, most of which I afterwards 

 observed had been fertilized, since their seeds ripened. These 

 plants must therefore have been fertilized by the pollen of other 

 specimens in their neighbourhood ; at least according to all our 

 present notions on this subject. But then the ovules of the 

 hybrid were also similarly circumstanced, and if they had been 

 capable of receiving the same influence from other plants, there is 

 no apparent reason why they should not have proved fertile, also. 



4. Ovules. In the parent plants, the ovules begin to grow 

 and develop themselves immediately after the fall of the corolla, 

 whilst in the hybrid they soon wither away. It is remarkable 

 however, that all symptoms of decay in the ovarium are strictly 

 limited to the ovules themselves, for even the little protuberances 

 upon which they are seated on the placenta remain succulent, 

 as do the various parts of the pericarp, including also the base 

 of the style : all which continue healthy and attain their perfect 

 dimensions, the valves alone slightly collapsing from the deficiency 

 of the ovules in the enlarged cells. Plate xvn. Fig. 4. But the 

 stigmatic tissue dries up, and a cavity is thus left through the 

 upper part of the dissepiment, forming an opening between the 

 two cells, Fig. 5. e. The same effect sooner or later takes place 

 also in the seed vessels of the parents. 



Recapitulation. In reflecting upon the points of resemblance and 

 of disagreement in the organs of fructification of these three plants. 



