Mr D. Don on the Affinities of Vellosia, Barbacenia, Sfc. ] 65 



umbilicus of the Hypoxidece. In Hypoxis erecta, the segments 

 of the perianthium and the stamina are frequently eight, and, 

 from the variation of these organs in other species of the genus, 

 the number of stamina therefore in Vellosia, will appear less 

 anomalous ; but it must be observed, that, in Vellosia, the divi- 

 sions of the perianthium are unaffected by the increased number 

 of stamina, which vary from 6, 12, 18, to 24; thus affording a 

 striking example of the unerring regularity of the laws of na- 

 ture. Dr Martins states that the stamina are sometimes 15, 

 and this number is easily reconcileable with a six-parted peri- 

 anthium, by considering them as exhibiting a quintuplicate of 

 the three inner segments of the perianthium only, and we should 

 expect to find them disposed into three bundles, and not into 

 six, which would be unnatural. We have already cited Hypoxis 

 erecta, as affording an example of occasional increase in the 

 number of stamina ; but there the increase is only partial ; and 

 therefore we find that the segments of the perianthium are in- 

 creased in proportion : for it appears to be a law, which Nature 

 never departs from, that, when any of the organs of fructifica- 

 tion suffer a partial increase only, the neighbouring parts are 

 also affected in number ; but when the increase is general, then 

 it becomes a multiplicate of the organ to which the increased 

 one is most analogous. The genus Lophiola may be mentioned 

 as exhibiting a considerable affinity with Hypoxis, particularly 

 in the structure of its seeds, which are cylindrical, ascending, 

 and attached to the placenta, by their slightly prominent umbi- 

 licus ; but the testa is scarcely crustaceous, although of a thicker 

 consistence than in the rest of Hremodoracea, which agree with 

 IridecB, in having a membranous testa. The chief distinction 

 between these two families depends, as Mr Brown has shewn, 

 on the situation of the stamina. In the Iridece, the stamina are 

 placed opposite the outer segments of the perianthium, and the 

 anthers face outwards ; while, in Hamodoracea, the stamina are 

 placed opposite the inner segments of the perianthium, and the 

 anthers face inwards. 



Additional Remarks. — Since the above observations were 

 written, I have been favoured by Robert Barclay, Esq. with a 

 ripe capsule of the Barbacenia purpurea, from his choice 



