54 



THE CACTACEAE. 



spines; radial spines 8 to 12, slender, the central one much longer than the others, 2 to 3 cm. long; 

 areoles 1 cm. apart, scarcely woolly except toward the top ; flowers 6 cm. long, somewhat tubular, 

 purplish to brownish, the ovary without spines or hairs; fruit globular, about 6 cm. in diameter, 

 naked but the surface somewhat warty; seeds black, shining, minutely pitted, 2 mm. long, oblique 

 at bases. 



Type locality: Near Victoria, Mexico. 



Distribution: Eastern Mexico. 



The spines of seedlings are yellow. This species flowered in the New York Botanical 

 Garden in June 1918. 



E- O. Wooton made a trip into eastern Mexico in 19 19 and obtained a photograph 

 of a large Cephalocereus, presumably this species. The plant was common on the coastal 

 plain and extended the known range of this species northwards. Mr. Wooton's locality 

 was on the Chamal Hacienda, about halfway between Matamoras and Tampico. 



41. Cephalocereus tweedyanus sp. nov. 



Sometimes only 1 to 2 meters high and much branched at base, or sometimes tall, 5 to 7 meters 

 high and branched above, with a large woody trunk; branches 8 to 10 cm. in diameter, ascending 

 or slightly spreading, bluish green when young, grayish green in age; ribs 7 to 9, obtuse; spines brown 

 when young; radial spines several, 1.5 cm. long or less; central spines often solitary, porrect, 2 to 

 3 cm. long; flowering areoles bearing long white wool; flowers 7 cm. long; inner perianth-segments 

 short, oblong, obtuse; scales and outer perianth-segments obtuse, purplish; fruit nearly globular, 

 about 4 cm. in diameter, reticulated. 



ib -*' 4 











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Figs. 78 and 79. — Cephalocereus tweedyanus. 



The species is based on two collections from widely separated localities in Ecuador, 

 one being from the Pacific coast near sea-level, and the other from east of the coast range 

 at an altitude of about 3,000 feet. The first was collected by J. N. Rose and George Rose 

 in thickets near Santa Rosa, Province Del Oro, October 18, 19 18 (No. 23494, type), and the 

 other east of Ayapamba, same province, October 15, 1918 (No. 23454). This is the first 

 species of Cephalocereus reported from Ecuador and is the most southern species known on 

 the west coast of South America. It is dedicated to Mr. Andrew Mellick Tweedy, who 

 assisted Dr. Rose in his Ecuadorean Expedition in 191 8. 



