50 T. Holm — Grooniia pauciflora. 



Art. VI. — Croomia pauciflora Torr. An anatomical study; 

 by Theo. Holm. (With one figure in the text drawn by 

 the author.) 



Many years ago Croomia was considered a member of the 

 Berber id aceod and an ally of Berberis, Caulophyllum, Diphyl- 

 leia, Jeff er soma and Podophyllum* with the admission, how- 

 ever, that .the examination of a single seed did not disclose 

 whether the plant was dicotyledonous or not, and that the 

 affinity in either case remained obscure. Several years later 

 the mistake was corrected by Gray himself and the genus 

 referred to the Boxburghiacew.\ Besides the American 

 species there is another one in Japan : G Japonica Mig., but 

 these two are the only ones, known so far, of this singular 

 genus. The monotypic Stichoneuron and the small genus 

 Btemona Lour. {Roxburghia Banks) are with Croomia the 

 only representatives known of the order. Habitually these 

 genera are quite distinct, Stemona being a tall climber, the 

 others low herbs ; the floral structures have been carefully 

 described by Gray, Bentham and Hooker, and Engler and 

 Prantl. A more detailed account of the morphology of the 

 flower as well as the anatomy of the vegetative organs of some 

 species of Stemona has been given by Mr. Lachner-Sandoval.J 

 In regard to Groomia Gray pointed out some few peculiarities 

 in the stem-structure, sufficient to prove that its systematic 

 position w^ould have to be sought among the Monocotyledones, 

 but otherwise the genus has not been studied from this particu- 

 lar point of view. 



Having received some fresh material from Alabama, we 

 have examined the internal structure of the vegetative organs 

 of Groomia, and the following notes may be considered as 

 supplemental to those of Mr. Lachner-Sandoval for illustrating 

 the comparative anatomy of this peculiar little order. A few 

 remarks upon the rhizome may, also, be inserted at this place. 



As stated above, Groomia pauciflora is a low herb with a 

 few green leaves and two- or three-flowered inflorescences near 

 the apex of the single stem. The rhizome represents a sym- 

 podium ; it is slender, horizontally creeping with stretched 

 internodes and scale-like, membranaceous leaves. The termi- 

 nal bud produces the aerial, flower-bearing stem surrounded at 

 the base by three scale-like leaves, while a bud from the axil 

 of the lowermost of these pushes out into a horizontal, sub- 

 terranean branch, which continues the direction and growth of 



* Gray, Asa : Genera floras Americae bor. -orient, ill. Vol. i, 1848, p. 90. 



f Same : On the genus Croomia, and its place in the natural system. (Mem. 

 Amer. Acad. Sc, Ser. 2, vol. vi, 1859, p. 453, plate 31.) 



X Beitrag zur Kenntniss der Gattung Roxburghia. (Botan. Centralb. , vol. 

 1, 1892, p. 65. 



