MEXICAN AND CENTRAL AMERICAN UMBELLIFER^ 1 39 



18. ARRACACIA Bancr. in Jamaic. Jour. 4: 18. 1826. 



A Mexican and Central American genus extending into South 

 America, with one species (the type) in Jamaica. Hemsley enumer- 

 ated twelve species, only five of which bear names. Of these A. 

 acuminata Benth. is referred below to Neonelsonia ; A. dectimbens 

 Benth. is referred below to Taiischia ; while A. glaucescens Benth. 

 is restricted to South America. This leaves but two of the named 

 species cited by Hemsley: A. atropiirpiirea Benth. & Hook, and A. 

 tolucensis Hemsley. Two species, cited by Hemsley under other 

 genera, we have transferred to Arracacia^ viz., Tauschia coulteri 

 Gray and Smyrniuni cegopodioides H.B.K. 



Since 18S0 fourteen new species of Arracacia from our region 

 have been described, five of which have been transferred to Tauschia. 

 In addition to these we describe below seven new species, making the 

 total enumeration of the species of Arracacia found in Mexico and 

 Central America reach twenty, all of which are endemic. Of the 

 four remaining species of the genus, three belong to South America 

 and one to Jamaica. 



The genus Arracacia appears to be properly characterized as con- 

 taining forms which are tall and branching, with ternate leaves, sharply 

 ribbed fruit, and conical stylopodium. The allied genus Tajtschia^ 

 on the other hand, contains forms which are low and acaulescent or 

 nearly so, with pinnate leaves, obtuse ribs, and no stylopodium. 



We present an enumeration of all the known species of Arracacia^ 

 with descriptions of new species and citations of collections received 

 since the publication of our former paper. 



1. Arracacia andina Britton, Bull. Torr. Bot. Club 18: 37. 1891. 



This species, collected by Dr. Rusby in South America, seems not 

 to be an Arracacia. 



2. Arracacia aegopodioides (H.B.K.) C. & R. Plate XI. 



Synyrmtim agopodicides H.B.K. Nov. Gen. & Spec. 5: 16. 1821. 

 Museniopsis cegopodioides C. & R. Contr. Nat. Herb. 3 : 302. 1895, as to 

 reference, but not as to plant. 



Hidalgo: on the Sierra de Pachuca, altitude 2700 meters, Pringle 

 6934, July 28, 1898 ; same station. Rose <& Hough 4481, June i, 

 1899; same station, Pringle 7905, October 5, 1899. 



The type of this species was collected by Humboldt & Bonpland 

 (altitude 2550 meters) and is now in the Berlin Herbarium. Through 

 the kindness of Dr. K. Schumann we have seen a fragment of the 

 type and also a photograph of it, which is here reproduced. Mr. 

 Pringle's plant seems to agree with it and the species is herewith trans- 



