Mr. J. Miers on the Solanacese. 9 



find genera placed heterogeneously together, without regard to 

 uniformity of character, and totally irrespective of the most im- 

 portant feature of aestivation. Tbvis, among the Solanece, which 

 possess a valvate aestivation, is placed the genus Nicandra, with 

 a corolla resembling that of a Convolvulus, the lobes of its border 

 possessing a decidedly imbricated aestivation. The want of at- 

 tention to this last-mentioned important chax'acter has, in the 

 same manner, led to the confused association of several genuine 

 sections : thus, among the Atropinece, we find the very natural 

 group of the Jahorosece, distinguished by a tubular corolla, which 

 in most cases grows black in drying, always possessing a valvate 

 aestivation and other very distinct characters, classed with Atropa 

 and Mandragora, genera quite different from- them and each 

 other, and possessing a remarkably imbricate aestivation. Thus 

 also in the Lijcinea, there is an equal amount of complication, 

 for we see Dunalia, lochroma, Pcecilochi-oma, Acnistus, and others 

 with valvate aestivation, associated with several distinct groups 

 that possess an imbricated aestivation : among these we find 

 Juanulloa, Solandra, &c., and also Marckea, Thinogeton, &c., and 

 all these again congregated with Lijcium — groups perfectly di- 

 stinct from one another. We meet with Juanulloa and Marckea, 

 having almost a straight embxyo, placed among a number of 

 genera having a nearly annular embryo. 



The genus Thinogeton, arranged by M. Dunal among his Ly- 

 cinece, is said to be closely allied to Jaborosa, Himeranthus, Dory- 

 stigma and Trechontetes, genera which he has singularly placed 

 among his Atropineee. This distinguished botanist can never 

 have seen a specimen or drawing of Thinogeton, or he woidd 

 never have ventured on such a conclusion : its affinity, as I have 

 elsewhere shown, is toward Scopolia, Physochloina and Cacahus, 

 genera that I have placed vnth. Hyoscyamus, on account of their 

 many uniform characters, particularly that of the operculiform 

 dehiscence of their fruit. 



In M. Dunal's tribe of the Daturerp, we meet with a similar 

 degree of irregularity, in the association of perfectly incompatible 

 genera. Thus Dictyocalyx is placed here, while Thinogeton is 

 arranged among the Lycinece, and yet these two genera are 

 identically the same. This genus with a spiral embryo, and 

 Datura with a nearly annular embryo, are associated with So- 

 landra, where the embryo is nearly straight or but slightly 

 curved ; in this respect M. Dunal has followed the example of 

 older botanists, who, for no other reason that we can imagine, 

 drew this conclusion, because in former times Solandra grandi- 

 jiora was the Datura scandens of Plumier. Solandra is as totally 

 distinct in habit from Datura as it is in structure ; it is a climb- 

 ing j)lant, with large coriaceous leaves and orange-coloured 



