28 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. X, NO. 2. 



arrangement of the calyx leaves, the posterior of these covering the anterior;" the somewhai 

 zygomorphic, gamopetalous corolla with the three stamens inserted at the apex of the corolla tube; 

 the turbinate ovary with a minute style and three long, subplumose stigmata. Having advanced 

 these brief remarks upon the generic characters of Claytonia and Mbntia, we might now pro- 

 ceed to describe some morphological and anatomical points in Claytonia, and, of course, we 

 receive the genus in the same way as it was understood before and outlined so well in the works 

 of Gray, Fenzl, Jussieu, Bentham and Hooker, Exgler and Prantl, etc. 



II. THE INFLORESCENCE. 



The aerial stems are in Claytonia nearly always terminated by an inflorescence, usually pre- 

 ceded by one pair of opposite leaves, which by Wydler and Eichler have been defined as fore- 

 leaves; the flowers themselves are mostly destitute of such foreleaves, but there are species in 

 which one of these, the fertile, is readily visible as a minute bract, especially in the lower por- 

 tion of the inflorescence. Frequently the foreleaves are the only leaves of the aerial stems, but 

 in some few species the stems are quite leafy from the base to the inflorescence in C. Chamis- 

 aon/'s Esch., where the leaves are opposite, while in C. linearis Dougl. and C. parvifolia Moc. 

 they are alternate. 



In regard to the inflorescence, this is of the cymose type, but seems never to be regularly or 

 completely developed in our genus. It sometimes begins as a very regular cyme, but the lateral 

 ramifications soon turn to monochasia of the type cicinnus or scorpioid cyme, as described by 

 Wydler*. Most complete is the cyme perhaps in ('. Sibirica L. ; the stem is terminated by a 

 flower, and a lateral inflorescence is developed in the axil of each of the two prophylla. The one 

 of these lateral inflorescences may continue this regular cymose ramification at least at intervals, 

 while the other, usually very soon, turns to a monochasium; nearly all the flowers are in this 

 species provided with one of the two foreleaves (the fertile), but they are relatively small, 

 especially in the monochasia. A like composition of the inflorescence may also be observed in 

 C. sarmentom Met., but in most of the specimens examined of this species a few-flowered 

 scorpioid cyme seemed to be the typical. In large specimens of C. linearis Dougl.. the inflo- 

 rescence begins as a cyme, but the lateral branches become immediately leafless monochasia of 

 the same type as described above; in small specimens, on the other hand, only one prophyllon is 

 developed, and the inflorescence consists only of one or four flowers representing a true 

 monochasium. 



Partly a true cyme and partly a scorpioid cyme is the inflorescence of C. megarrhiza Parry 

 and ('. arctica Adams; an apparently regular cyme is to be found in C. Chamissonis, Esch., at 

 least in the lower portion, but while the one lateral branch becomes a four or five flowered leaf- 

 less monochasium. the other most frequently develops as a long vegetative shoot. In the other 

 species which we have examined a scorpioid cyme is the only kind of inflorescence represented, 

 mostly with the secondary prophylla entirely suppressed, as in C. Virginica L., C. Caroliniana 

 Michx., C. asarifolia Bong., < '. parritfora Dougl., C. lanceolata ■ Pursh, C. gypsqphiloides 

 Fisch. et Met., (\ spatkulata Dougl.. and C. arenicola Hend. ; the last species possesses long, 

 many-flowered monochasia in which all the flowers are provided with a prophyllon. In C. 

 parvifolia Moc. the inflorescence has only very few flowers, since the one of the two lateral 

 branches, as it seems, constantly develops into a vegetative shoot; this species is, furthermore, 

 peculiar by the two opposite prophylla being developed only as minute, hyaline, and scale-like 

 leaves, besides that the numerous stem leaves subtend small bulblets, which are said to fall off 

 and to develop new individuals. 



"Almquist S. Om blomdiagrammet hos Montia (Botan. Notiser 1884: 156, and Botan. Centralbl. 21:91. 1885). 

 The fruit and the seeds in Moulin, as well as the mechanism by which the seeds are ejected, is carefully described by 

 Professor Urban (Jahrb. hot. Garten Berlin 4:256, 1886). 



b Flora, 1851: 348. 



