1923] Ottley: A Revision of the Calif ornian Species of Lotus 193 



been segregated into several genera : Hosackia Benth., Acmispon Kaf., 

 Syrmatitim Vogel, and AnisoJotus Bernh, 



4. The genus Hosackia has been recognized as including the greater 

 number of American species, while at the same time certain of the 

 sjjecies were remanded to the Old World genus Lotus. 



Reasons for Remanding the New "World Species to the 

 Old World Genus Lotus 



While the North American species have been assigned to two or 

 more distinct genera, the species which form the most well-marked 

 group are those which have been referred to the genus Syrmatium 

 (subgenus Syrmatium of this paper). In general they are char- 

 acterized by small indehiscent arcuate legumes which with the per- 

 sistent calyx and pedicel are deciduous at maturity. These characters, 

 however, with the exception of the deciduous fruit, are not constant 

 for all the species assigned to the group. The legumes of some 

 may be tardily dehiscent, as has been observed in the case of Lotus 

 eriophorus Greene (Syrmatium eriophorum Heller), while two of the 

 species, Lotus glaher Greene (Syrmatium glabrxim Vogel), and Lotus 

 leucophyllus Greene (Syrmatium sericeum Greene), have straight or 

 slightly falcate legumes. The leaves, inflorescence, and flowers possess 

 only those characters which have their counterpart in many of the 

 species of the groups Hosackia and Acmkpon. The deciduous fruit 

 is therefore the only distinguishing character which is constant for 

 the Syrmatium group. Shall we recognize such a character as of 

 sufficient importance to justify the formation of a new genus? Of 

 this Greene (1890) says: "Since the jointed pedicels and deciduous 

 fruiting calyces of for example the Lag opus subgenus of Trifolium 

 are not to be of generic import, neither may they be so treated in 

 this group of Lotus which has been called a genus under the name 

 Syrmatium." 



A consistent treatment of the remaining species would demand 

 recognition of at least five generic groups: (1) Hosackia Benth. 

 including those species with stipules, (2) Acmispon Raf. represented 

 by L. americanus Bisch. with its three-foliolate leaves, (3) Anisolotus 

 Bernh. embracing L. suhpinnatus Lag., L. humistratus Greene, and 

 L. denticulatus Greene, all having seeds and corollas that differ 

 slightly from those of the other American species, and (4 and 5) two 

 additional genera separated b}'' characters of corolla and stigma. 



