MEMOIRS FROM THE DEPARTMENT OF BOTANY OF COLUMBIA UNIVERSITY 5 



genera, that, in my opinion, really deserves generic rank is DrymocalHa. The first two 

 may, perhaps, have some, although very slight, claim to such rank ; the others, none 

 whatever. Drymocallis was based upon P. rubricaulis Jordan, an unpublished "species. 

 Tourreau gives as a synonym, "P. rupestris L. ex parte." I have also found another ref- 

 erence which states that P. rubricaulis Jordan is a form of P. rupestris. Drymocallis, 

 therefore, represents the group of plants which would have borne the name Bootia Bigel., 

 if that had not been antedated, i. e., P. arguta and its allies. 



In 1829, Bunge ^ established the genus Chamaerhodos on those species o{ Sibbaldia 

 that have a basal style and lack bractlets, whose leaflets are once or twice ternately 

 divided and whose 5 stamens are antipetalous. 



GEOGRAPHIC DISTRIBUTION. 



PotentUla (in the broader sense) and Fragaria are distributed throughout the colder 

 temperate zone of the northern hemisphere, extending far into arctic regions. Although 

 less common, they are also found in alpine and high mountain regions of the tropics 

 and South America. P. anserinoides is a native of New Zealand. Sibbaldia and Goma- 

 rum grow in the arctic and colder regions of the northern hemisphere, but the former is 

 also found on the alpine peaks of Europe, Asia and ISTorth America. Chamaerhodos is 

 mainly Siberian, but G. erecta also grows in northwestern America. Horkelia (includ- 

 ing Ivesia) is confined to the western part of North America. Duchesnea is native of 

 Southern Asia, but is introduced into North America. 



ECONOMIC VALUE. 



The economic value of the plants of the tribe is not very great. Several species of 

 PotentUla are more or less good pasture plants, and a few furnish honey. The root of P. 

 Anserina serves as an article of food to the natives of Siberia and on the Scottish islands 

 Tiree and Coll. The fleshy receptacle of the species of Fragaria (the " strawberry ") is 

 relished by people of all nations as well as by animals. The dried leaves of P. fruticosa 

 are used in Siberia as a substitute for tea. The roots of P. argentea, P. Tormentilla and 

 Comarum palustre are used for tanning and dyeing red. The root of P. erecta (Radix 

 Tormentillae) is used as a powerful astringent medicine. In old time strawberries were 

 used as a medicine for gout and other diseases. 



Un Ledeb. Fl. Alt. 1 : 429. 1829. 



