PEIMARY DIVISION 19 



MONOGRAPH OF PHORADENDRON 



GENERIC DESCRIPTION 



Parasitic more or less fleshy suffruticose perennial exogens, usually 

 brittle at the nodes. Leaves opposite, usually petioled or petiolately 

 contracted, in a few species reduced to scales. Inflorescence of axillary 

 or sometimes also terminal mostly several- jointed spikes. Flowers sessile, 

 usually sunken in the rachis, in 1 or usually 2 to 3 or occasionally 5 

 series over each of the opposite scales in which the joint below ends, 

 small and inconspicuous, apetalous, dioecious or monoecious, 3- or occa- 

 sionally 2-, 4-, or 5- merous: sepals distinct, deltoid, valvate, persistent 

 on the fruit: stamens inserted on the base of the sepals with nearly 

 sessile 2- celled anthers dehiscing by subapical slits or pores: ovary in- 

 ferior, 1- celled, 1- ovuled: style short with scarcely dilated terminal 

 stigma. Fruit baccate, with a single albuminous seed surrounded by a 

 loosely fibrous endocarp and an extremely viscid mesocarp. Phoraden- 

 dron Nuttall, Journ. Acad. Philadelphia, ser. 2. vol. 1. p. 185. 1847. 

 Spiciviscum Engelmann in Gray, Mem. Amer. Acad. n. s. vol. 4. p. 58. 

 1849. Allobium Miers, Ann. & Mag. Nat. Hist. ser. 2. vol. 8. p. 178-9. 

 1851. Baratostachys Uphof, Pflanzengattungen. p. 173. 1910. 



PRIMARY DIVISION OF THE GENUS 



Without cataphyllary scales. BOREALES. 



With cataphyls at least on the basal internode of each branch. 



AEQUATORIALES. 



I. BOREALES. 



Stems without cataphyls or scales toward the base of the branches, 

 never dichotomous though sometimes with one lateral branch developed 

 so as nearly or quite to equal the main axis, scarcely ever sharply 

 angled or 2-edged. Spikes axillary, never terminal. Flowers dioecious, 

 the staminate and pistillate spikes often dissimilar. Confined to conti- 

 nental North America; characteristic of the northern Mexican table- 

 land and the southern and western United States, only two species 

 reaching into Central America. 



Branches never winged : receptacular cups not lacerate. 



Pistillate flowers 2 on each joint. Chiefly on conifers. PAUCIFLORAE. 

 Pistillate flowers 6 or more on each joint. PLURISERIALES. 



