4 Mindeskrift for J. Steenstrup. XXI. 



establishing five sections viz. Euclaytonia, Limnia, Alsinastrum, Naiocrene and Montia- 

 strum. Characteristic of Euclaytonia is the relatively large, primary, persisting root; in 

 Limnia the roots are fibrous, and the species mostly annual. Then in Alsinastrum we 

 have the peculiar Cl. Chamissonis with all the leaves opposite, and with bulbiferous 

 stolons; in Naiocrene which is, also, perennial, bulblets are developed in the axils of many 

 of the cauline leaves. Finally in Montiastrum the species are strictly annual with mostly 

 alternate leaves, and with mostly two of the stamens suppressed. In other words several 

 of the species are annual, and among those which are perenniaJ we meet with some that 

 possess large persisting roots, and others in which these are fibrous and fugacious, but 

 where the vegetative reproduction is secured by means of bulblets, aerial or subterranean. 



Now in respect to the structure of the shoot, we have shown^) that the inflores- 

 cence is frequently lateral, and indeed most frequently so. The inflorescence is of the 

 cymose type, but the lateral ramifications are frequently monochasia of the type cicinnus 

 or scorpioid cyme, as described by Wydler^). Preceding the inflorescence we frequently 

 notice one pair of opposite leaves, which by Eichler and Wydler have been defmed as 

 prophylla; the flowers themselves are mostly destitute of such foreleaves, but there are 

 some species, however, in which one of these is developed, especially in the lower part 

 of the inflorescence. Most frequently the two foreleaves, preceding the inflorescence, 

 are the only leaves of the aerial stems, but in some few species, as will be shown later, 

 the stems are leafy from the base to the inflorescence, opposite in Cl. Chamissonis, alter- 

 nate in Cl. linearis and parvijolia. 



In outlining the genus Gray (1. c.) did not distinguish between species with the shoot 

 terminated by an inflorescence or being purely vegetative, nor did he consider the cha- 

 racter "annual" or "perennial" of much importance to his classification. Nevertheless 

 in all the members of Montiastrum the shoot is terminated by an inflorescence, but not 

 so in any of those of Limnia. The duration of life of these species, annual or perennial, 

 does not seem to be of any importance, inasmuch as we know that annuals sometimes 

 become perennial, and in Claytonia this is illustrated by Cl. Sihirica according to Gray 

 (1. c). 



Let us now examine the types of the genus, classified as suggested by Gray, and 

 considered inseparable from the genus Claytonia. 



Euclaytonia. 



Claytonia megarrhiza Parry (Plate I figs. 1 — 15). 



Undoubtedly the most remarkable of the genus. A seedling has been figured on 



Plate 3 fig. 1, and we notice the distinct primary root, the short hypocotyl, and the two 



') Memoirs U. S. National Acad. of se. Washington 1906, p. 29. 

 2) Flora 1851, p. 348. 



