3. Epistamineae here the ovarium is inferior cohering with the tube of the calyx, stamens, inserted on the limb, or superior. Santalum album, (Sandal -wood) and Aristolochia (Birth-wort or snake-root) are well known examples of this section.
4. Declines Flowers unisexual or without a perianth. To this tribe are referred Euphor- biaceae, Urtiaceae, Piperaceae, besides the Oak, Alder, Birth, Willow, Pine,Walnut, &c. Judging from thg dissimilarity of the plants associated under this name, bearing in mind at the same time that several other orders in which declinous flowers predominate are scattered through the system, it is to be hoped future researches will tend to break up this class and by the removal of some of the orders establish a more natural distribution of the remainder : some of those now placed here seemto have been referred to it, as to a lumber room, from not knowing where to dispose of them to greater advantage.
For the remaining portion of the system Monocotyledons and Acotyledons. I shall refer for the present to the subjoined tables, the first exhibiting a Clavis of the system of Jussieu, the next, that system has modified by DeCandolle and adopted in our Prodromus.
I— COTYLEDONS none. Class 1. Acotyledones. II.— MONOCOTYLEDONES. 2. Monohypogynce, stamens hypogynous. 3. Monoperigynce, stamens perigynous. 4. Monoepigynce, stamens epigynous. III. — DICOTYLEDONES. § I. Apetai.^. 5. Epistaminea, stamens epigynous. 6. Pe?-istaminece, stamens perigynous. 7. Hypostaminece, stamens hypogynous.
- 2. MoNOPETALjE.
8. llypocorolla, corolla hypogynous. 9. Pericorolloe, corolla perigynous. 10. Epicorolla synanthe?-ce, corolla epigynous, an- thers united. 11. Epicorolla corisantherce, corolla epigynous, an- thers free. § 3. Polypetal.se. 12. Epipetalce, stamens epigynous. 13. Peripetala, stamens perigynous. 14. Hypopetalce, stamens hypogynous. § . Diclines. 15. Diclines, flowers unisexual, or -without a perianth. A. DICOTYLEDONES, Jussieu. — Exogenje, DC. I. THALMIFLOBJE, DC. — CI. 1. Hypopetala;, Juss. II. CALYCIFLOBJE, DC. CI. 2. Peripetalae, Juss. 3. Epipetalae, Juss. 4. Epicorollae corisantherae, Juss. 5. Epicorollae synantherae, Juss. 6. Pericorollee, Juss. III. COROLLIFLOILE, DC. — CI. 7. Hypocorollae, Juss. IV. MONOCIILAMYDEiE, DC. CI. 8. Hypostamineae, Juss. 0. Peristamineee, Juss. 10. Epistamineae, Juss. 11. Diclines, { f i" Angiospermae. ( § 2. Gymnospermae. B. MONOCOTYLEDONES, Juss.— Endogen^ Pha- nerogams, DC. CI. 12. Monoepigyneae, Juss. 13. Monoperigynae, Juss. 14. Monohypogynae, Juss. C. CI. 15. ACOTYLEDONES, Juss. § 1. Ductulosae, Am. — Endogenae Cryptogamae, DC. § 2. Eductulosas, Am. — Cellulares, DC.
Of this system I have only further to observe that the three primary divisions Acotyledons, Monocotyledons, and Dicotyledons are strictly natural and must always be retained in every Botanical system professing to arrange plants according to their affinities. So much can-not be said for the classes: they rest with one exception on a single point of structure not in itself invariable, in the respective classes; the insertion namely, of the stamens and petals, whether hypogynous or perigynous, points not always determinable without the aid of analogy. The secondary divisions according to which the classes are grouped under four sections are still more artificial and more liable to vary, and thence so much the less to be depended upon. Though to this extent artificial, this method of arranging the almost innumerable forms met with in the
