Rydberg: Notes on Rosaceae 541 



merge them into Eriogynia, or Luetkea, as was done by S. Wat- 

 son, O. Kuntze, and E. L. Greene, is rather indefensible ; and it is 

 strange that A. A. Heller, who recognized Petrophytum caespitosum 

 and P. elatior as representing a distinct genus, should transfer the 



Sp 



In the Flora are 



recognized five species of Petrophytum. Of these one, viz., P. 

 acuminatum, is proposed as new. It is known only from the type 

 locality. Kelseya is monotypic. 



Luetkea 



It is doubtful which of the two names, Luctka or Eriogynia, 

 is the older. Otto Kuntze, when adopting Luetkea instead of 

 Eriogynia, claimed that the former was published in 183 1 and the 

 latter in 1833. It is most probable that they were both pub- 

 hshed in 1832. The part of the Memoirs of the Academy of St. 

 retersburg in which Bongard's paper on the vegetation of Sitka 

 u 'as published, appeared in August, 1832. Whether any sepa- 

 rates were distributed before that time we can not ascertain. 

 mogynia was published in 1832, apparently in the later part of 

 be year, but the exact date is unknown. For that reason I did 

 n °t change the now accepted name of the genus. 



The generic name was originally spelled Li'itkea. As the 

 ^rman u is not found in Latin, it is usually replaced by ue. 

 Luetkea is therefore preferable to Lutkea. 



Aruncus 



hav 



The plants of this genus native to the eastern United States 



e invariably much smaller fruit than the European plants. 

 fhe plant common in the Alleghanies has thinner, more glossy 

 eav es and rather thick fruit. It is Aruncus sylvestris americanus 



Maximovicz, but unfortunately the synonym, 

 ain encana Pers., from which Maximovicz adoj 

 Ver y doubtful. It may belong, as well as all the synonyms under 

 • alleghanensis, except the last, to Astilbe instead of Aruncus. 



nc e a new name was proposed. 



Sp 



A 



H 



Missi 



^escent leaves and more slender fruit. It was described under 



the "*me of A. pubescens 



