This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Rootstocks usually very large and tuberous, stems usually twining, and climbing by means of the spirally coiling appendages of the petiole. Lower leaves reduced to scales; upper leaves entire or lobed. Flowers regular. Perianth-segments distinct, deciduous. Pedicels borne on a globose or conic receptacle, inserted in small pits, generally among minute bractlets. Filaments inserted on the bases of the perianth-segments. Staminate flowers without an ovary. Pistillate flowers usually smaller than the staminate, with an ovary and usually with 1-6 abortive stamens. Berry black, red or purple (rarely white), with 3 strengthening bands of tissue running through the outer part of the pulp, connected at the base and apex. Embryo lying under a tubercle at the upper end of the seed. [Ancient Greek name, perhaps not originally applied to these plants.]
* Text contributed to the first edition by the late Rev. Thomas Morong.
About 225 species of wide distribution, most abundant in tropical America and Asia. Besides the following, about 12 others occur in the southern United States and 1 in California and Oregon. Type species: Sniilax aspera L.
Stem annual, herbaceous, unarmed. [Nf.mexia Raf.]
Petioles tendril-bearing; stems climbing.
Leaves usually ovate, thin.
Leaves usually hastate, coriaceous.
Petioles without tendrils or nearly so; stems erect.
Stem perennial, woody, usually armed with prickles
Berries black or bluish-black.
Fruit ripening the first year.
Leaves green on both sides.
Leaves rounded or lanceolate, 5-nerved.
Leaves ovate, 7-nerved.
S. hispid a.
Leaves round-ovate, often narrowed at the middle, 7-9-nerved.
Leaves deltoid or deltoid-hastate, 5-7-nerved, often with 1 or 2 additional nerves on
Fruit ripening the second year; leaves elliptic or lanceolate, evergreen.
Leaves ovate or ovate-lanceolate, base rounded; berries bright red.
Leaves lanceolate, acute at the base; berries dull red.