The status of Tiarella macrophylla Small 

 t)LGA Lakela 



Dr. John K. Small in 1903 described Tiarella macrophylla 

 as an additional eastern representative of the genus. ^ The 

 curious fact that no plant has since been found to answer this 

 description has been of prolonged interest to the collectors of 

 the region. Dr. Small himself makes the following comment^: 

 "It is impossible to tell whether this species is starting on its 

 career or if its restricted range is the remnant of a former wider 

 distribution." 



In connection with a monographic study of the genus Tia- 

 rella now under way, the writer has examined the type specimen 

 of T. macrophylla, through the courtesy of the New York 

 Botanical Gardens where it is deposited. The specimen was 

 collected by A. ]\I. Huger, 1896, on Tryon Mountain, North 

 Carolina. It is small wonder that it has never been duplicated, 

 since upon careful study it has been found to consist of the 

 basal leaves of Heuchera villosa and the flowering stems of 

 Tiarella. 



On the sheet are an entire flowering stem bearing cauline 

 leaves, and a part of another inflorescence, both in frXrrt and 

 flower. The cauline leaves attached to one of the inflorescences 

 are typical leaves of the southern form of T. cordifolia. Neither 

 runners nor attached basal leaves are present. The two detached 

 basal leaves, the only ones on the sheet, each with the base of 

 the petiole broken off and missing, are obviously the leaves of 

 Heuchera villosa with which they agree, not only in morphology 

 but in the anatomy of the petiole, which is very different from 

 anything found in the genus Tiarella. 



According to the International Rules, a name is to be re- 

 jected when it is based on altogether incoherent elements. 

 Tiarella macrophylla Small seems completely to fulfill this re- 

 quirement. 



University of Minnesota 

 Minneapolis, Minn. 



^ Flora of the Southeastern United States, p. 502. 1903. 

 2 Manual of the Southeastern Flora, p. 594. 1933. 



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