500 CONTRIBUTIONS TO 
species are all erect plants with woody stems, and fascicu- 
late, terete, or 3-gonous leaves, while those of the latter are 
herbaceous, prostrate plants, with geminate broad, fleshy 
leaves, which in every case appear decurrent on the stem. 
I have had no opportunity of examining more than one out 
of the 5 species of Nolana enumerated by Dr. Lindley, and 
that has not enabled me to appreciate the distinction between 
that genus, Sorema, and Alona. In Nolana the species are all 
succulent prostrate plants, mostly with geminate leaves, 
which are both petiolated, and are not decurrent on the 
stem, asin Sorema ; in all the 3 genera the flowers closely 
resemble each other; in Nolana tenella, Lindl, I found 5 
nuts, which were either 1-3-4 or 5-celled ; if no difference 
then can be detected in the flower or the seeds, habit alone 
remains to draw a line of distinction between them, and a 
question arises whether habit alone will be considered suffi- 
cient to separate these plants into 3 genera. Should they 
all verge into No/ana, this genus might then with propriety 
be divided into 3 sections:—1. Eunolana, comprising the 
5 species alluded to; 2. Sorema, containing the 7 species 
above enumerated ; and 3. Alona, embracing 8 species, viz 
1. A. celestis, 2. A. rostrata, 3. A. obtusa, 4. A. glandulosa, 
5. A. carnosa, and 6. A. baccata of Dr. Lindley, together 
with two new species described below. It is to be hoped 
that some Botanist, possessing the means of examining these 
plants, if possible in the living state, will observe whether 
any tangible and constant characters exist between them, 
or whether from the similarity of their structure, they should 
all become referrible to Nolana as above suggested ; but in 
the mean time it is not unfair to presume, from the indica- 
tions alluded to, that some good generic differences may yet 
be discovered, when the plants have been more carefully 
examined. 
7. Alona ericifoiia (n. »j :—fruticulosa, glanduloso-pube- 
scens, ramulis sub-dichotomis ; foliis fasciculatis confertis 
linearibus, margine revolutis et tunc teretibus; floribus 
speciosis cæruleis ; éalyce tomentoso, tubo 5-gono, lobis 
