A new species of Talinum from Trans-pecos Texas 



C. H. Mueller 



In July of 1932 the author collected numerous specimens of 

 an apparently undescribed species of Talinum in the Chisos 

 Mountains of Western Texas. The plant was found in one local- 

 ity scattered on the dry, grassy, sloping banks of a southwester- 

 ly directed arroyo at about 6500 feet altitude. Two specifically 

 undesignated specimens of the same plant in the herbarium of 

 the University of Texas prove that it had been collected pre- 

 viously by Dr. M. S. Young as follows: "Summit of Mr. Liver- 

 more, Davis Mountains, August 15, 1914," and "Very abundant 

 on high, rocky slopes, Pine Canyon, Guadalupe Mountains, 

 Texas, August 15, 1916." The range of this plant, then, is the 

 mountains of Western Texas and probably of Southeastern New 

 Mexico and Northern Mexico. 



The material is very distinct from other species examined 

 and from the descriptions of Mexican species. 1 The most closely 

 related species seems to be Talinum calycinum Engelm., which 

 differs materially in having a long peduncle, somewhat longer 

 leaves, and a relatively longer style as compared with the fila- 

 ments. For this new species is proposed the name Talinum 

 Yonngae in recognition of Dr. Young's much earlier collection 

 of the plant and of her tireless work in a country which was then 

 relatively unsettled and must have confronted her with many 

 hardships. A description follows: 



Talinum Youngae sp. now Perennial from a much branched, 

 large, fleshy root; glabrous; stems several, leafy, spreading, 

 typically branched and 8 to 10 cm. tall (rarely as short as 6 

 or as tall as 15); leaves densely but evenly distributed, not 

 rosette-like, sessile, the upper linear, nearly terete, 10 to 28 mm. 

 long and 1 to 2 mm. broad, the lower shorter, broader, and 

 manifestly more flat, each (regardless of position on the stem) 

 subtended by a free, flattened margin extending entirely around 

 the base below the point of attachment; peduncles axillary, 3 

 to 15 mm. long (usually 10 or less), 1 to 3 flowered (usually 3); 

 pedicels 10 to 20 mm. long, each with 2 acute bracelets about 



1 Rose and Standley, Contr. U. S. Nat. Herb., vol. 13, pt. 8, 1911. Wilson, 

 N. Am. Flora, vol. 21, pt. 4, 1932. 



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