Mr. J. Miers on several genera hitherto placed in Solanacese. 175 



tliis tribe, Scopolia, Physoclcpna, Thinogeton and Cacahus, genera 

 which offer a striking affinity to one another in their most essen- 

 tial characters, and there can be httle doubt that they all form 

 a portion of one very distinct group. These characters coincide 

 for the most part with those of Hyoscijamus, and the only con- 

 sideration wanting to complete their affinity is the aestivation of 

 their corolla. The funnel-shaped and almost entire border of 

 the corolla in those genera would almost necessarily imply the 

 regular plicature of its campanular portion, but it is probable 

 that at the same time the lobes in aestivation may be somewhat 

 imbricate, as is distinctly observable in Nieremhergia and Petu- 

 nia. It is impossible to determine this question from dried spe- 

 cimens, and it can only be ascertained from the examination of 

 living plants. Should the aestivation be found, on the contrary, 

 to be entirely induplicato-\'alvate, these four genera would not 

 belong to Atropacea, but must be referred to SolanacecB, where 

 they would naturally find their place as a capsular tribe preceding 

 the JaborosetB. 



8. Atropea. — This very distinct group is distinguishable from 

 the other tribes by its baccate fruit, and its ovary devoid of a 

 fleshy epigynous gland. The first four genera possess a perennial 

 root, with numerous deciduous herbaceous stems, large showy 

 flowers, and a somewhat shrubby habit, with dense foliage and 

 large leaves. Lycium, on the contrary, is a straggling shrub with 

 woody stems, and frequently with spinous branches : its flowers 

 are small. These diff"erences are only generic, and do not offer 

 sufficient reasons for separating the latter genus as a tribe distinct 

 from the others. 



no apparent h3pogynoiis disc is to be seen among tlie P r mulct ce(t, it is oc- 

 casionally discernible, but I believe only in those genera where the capsule 

 bursts into valves by the longitudinal carpellary nervui'es, as in Lysimachia, 

 of which genus Nees v. Esenb. in his ' Gen. PL Fl. Germ.' says distinctly, 

 " Germen liberum basi disco aniniliformi cinctum." This view of the case, 

 though quite hypothetical, is rendered still more probable by the facts ob- 

 servable in the capsule oi Plaiitago. which offers a membranaceous pyxi- 

 dium very similar to that oi Jnagallis. At an early period the future trans- 

 verse line of dehiscence is discernible in the ovarium, as in Anayallis, but it 

 is then more approximate to the base, proving that the growth of its lower 

 portion is afterwards more considerable than the upper part; as it advances 

 towards maturity the zonal line becomes more marked, the upper portion 

 of the pericarpial covering being of a deeper green hue and more opake, 

 while the lower moiety is distinctly hyaline and transparent, and of more 

 slender texture ; on becoming ripe, the greater indurescence of the upper 

 half, by desiccation, is still more evident, facts whic hlead to the only reason- 

 ab'e conclusion, that the upper portion of the ovarium is covered by a very 

 th.n epigynous glandular covering, as in Hyoscijamus, but too thin to be 

 readily detected in parts of such very slender texture : that it does exist, is 

 however proved by the circumstance of that part of the pericarpial covering 

 being always less pervious to light, when viewed under the microscope, than 

 the lower moiety. 



