240 PITTONIA. 
proved to be by no means the banner, but one of the wing- 
petals, its mate being one of those two small ones at the top 
of the flower. The real banner-petal, perfectly demonstrated 
as such by its position in the bud as enfolded by the wings, 
is the large concave lateral petal at the left-hand side of the 
flower. In the accompanying illustration figure 1 repre- 
sents very accurately the corolla of Cassia Marylandica, b in- 
dicating the banner-petal, w w the wings, k k the keel. Fig- 
ure 2 as perfectly displays the same organ in what is called 
in our books Cassia Chameecrista, the same letters indicating 
the petals by name. It will thus be seen that what marks 
Fig. 1. Fria. 2. 
so strangely the Chameerista corolla is not an inversion, but 
something still more interesting and curious, namely, a tor- 
sion of ninety degrees to left—a character which, by itself 
alone, if cónsidered in connection with the peculiar habit 
of the plant and its rather numerous allies, would estab- 
lish the whole group as securely in the rank of a distinct 
genus as any genus could need to be established. I shall, 
however, here enumerate the actual characters of the genus 
CHAMÆCRISTA as I have recently observed them in living 
plants, and in dried specimens of many species. (1.) Flow- 
ers axillary or supra-axillary and solitary or few and fas- 
cicled, never terminally clustered as in Cassia. (2.) Buds 
