164 



Mr. J. 



[iers on the Bignoniacese. 



bably be more readily understood from the examination of the 

 ovary. This is here compressed, as in the former tribe, 2-celled, 

 with a precisely similar style and stigma; but the dissepiment is 

 not, in like manner, parallel to its two faces, but, contrariwise, 

 transverse, its ovuligerous margins corresponding with the antical 

 and postical longitudinal ridges ; the cells, therefore, instead of 

 being anterior and posterior in regard to the axis, stand on its 

 right and left, so that the stigmata are contrary to the cells : 

 the ovules, in two series, are borne upon the dissepiment (in 

 Tecoma ochracea) (fig. 6), not along the axis, but, as in the 



Fig. 6. Fig. 7. Fig. 8. 



former instance, at the utmost distance from it. Now, in this 

 case the ovary may be assumed to be constituted either of two 

 carpels, ovuligerous on their midribs, and placed back to back, 

 as in fig. 7 j or it may be formed of four carpels arranged some- 

 what as in the Bignuniece, but differently disposed, as in fig. 8, 

 the sterile margins being afterwards united, and the adjacent 

 faces becoming confluent. Upon comparing these figures, it 

 will be seen that the former view must be rejected, because, 

 under that hypothesis, the ovules ought to be found arranged 

 along the axis ; and the latter view must be adopted, because it 

 satisfactorily accounts for the position of the ovules in the ovary 

 and of the seeds in the fruit. Owing to a somewhat different 

 inclination of the carpels, as shown in fig. 9 (which will be seen 



Fis. 9. 



Fig. 10. 



to be a modification of fig. 8), the ovary and fruit become 4- 

 locular in Heterojjhragma ; and the resulting form of fruit is 

 shown in fig. 10, where the dissepiment is cruciform, with two 

 longer and two shorter arms ; the latter, bearing the seeds 3- or 

 4-serially on both sides, terminate in the middle of the valves, 

 the former touching the sutural and dehiscent margins of the 

 valves. When the valves open, the corresponding barren portion 

 of the dissepiment becomes split across into two longitudinal 

 halves, each half bearing the seminigerous portion of the dis- 

 sepiment in the form of the letter T, which at the same time 

 detaches itself from the middle of the valve. We see here the 

 most complete verification of the hypothesis above suggested of 



