164 THE GENUS PHORADENDRON 



the drainage of the Orinoco and Amazon rivers; (17) Orinocan re- 

 gion, like the Amazonian appearing as a barrier to distribution rather 

 than a distributional region for Phoradendron; (18) Venezuelan re- 

 gion, a meeting point of the Isthmian, Andean and Caribbean regions ; 

 (19) Galapageian region, essentially an oceanic extension of the Vene- 

 zuelan and Andean regions. 



West Indies: (20) Caribbean region, as far north as the Anegada 

 passage; (21) Antillean region; (22) Bahamian region, in Phoraden- 

 dron showing absolute isolation from the adjacent Atlantic region of 

 Florida. 



Plate 1. HABIT. Phoradendron villosum, on Quercus. Photo- 

 graphed in California by George E. Nichols. Greatly reduced. 



Plate 2. HABIT. Plioradendron Libocedri, on Libocedrus, at the 

 entrance to the Yosemite valley, California. Photographed by George 

 D. Fuller. P. juniperinum, on Juniperus, at the rim of the grand 

 canon, Arizona. Photographed by Charles F. Hottes. Both greatly 

 reduced. 



Plate 3. MORPHOLOGY of foliage in the Aphyllae. a. Phoradendron 

 juniperinum, with scales not constricted at the base (Wright), b. P. 

 ligatum, with scales constricted at the base (Oregon, Cusick, the 

 type) . x 10. 



Plate 4. MORPHOLOGY of the Aphyllae. Plioradendron juniperinum, 

 showing scale-like leaves, fruiting spikes each of a single 2-flowered 

 joint, and globose berry-like fruit with parted sepals (Arizona, Grif- 

 fiths, from fresh material), x 5. 



Plate 5. MORPHOLOGY of spikes in the Flavescentes. 



a. Staminate spikes of (from left to right) Plioradendron flaves- 

 cens (Missouri, Eggert), P. flavescens orbiculaium (northern Texas, 

 Bush), P. macrotomum (Florida, Curtiss), P. Engelmanni (southern 

 Texas, Lindheimer), P. Engelmanni Claviger (southern Texas, Tre- 

 lease), P. villosum (Oregon, Engelmann), P. Cocker ellii, (New Mex- 

 ico, Metcalfe), P. macrophyllum (Arizona, Gilbert), and P. Coryae 

 (Arizona, Blumer). Allx3. 



b. Pistillate spikes of (from left to right) Phoradendron flaves- 

 cens (Virginia?, Curtiss), P. macrotomum (Florida, Curtiss,), P. En- 

 gelmanni (southern Texas, Lindheimer), P. villosum, in fruit (Oregon, 

 Howell), P. Cocker ellii (New Mexico, Metcalfe), P. macrophyllum 

 (Arizona, Blumer}, and P. Coryae (Arizona, Thornber). All x 3. 



