656 



swingle: severinia buxifolia 



In the Rijks Herbarium at Leyden there is an apparently authentic 

 specimen of Citrus emarginata Desf., possibly a merotype, which is 

 undoubtedly Severinia buxifolia. 



RELATIONSHIPS 



Severinia, in spite of its being referred to Atalantia by all 

 recent botanical writers, is not at all closely related to the typical 

 species of that genus. In its fruit characters it resembles Tri- 



Fig. 1. Severinia buxifolia. Twig bearing flowers and fruits, and showing 



emarginate leaves and sharp spines. 



Scale §. 



phasia, but it has very different flowers, leaves, and twigs. Pos- 

 sibly Severinia may prove to be related to the aberrant Ata- 

 lantias, A. disticha (Bl.) Merr., A. linearis (Bl.) Merr., A. mari- 

 tima Merr., etc. Its affinities are certainly with Triphasia and 

 other members of the tribe Citreae, rather than with Claucena 

 or Micromelum. It is, however, distinctly not one of the true 

 citrous fruits constituting the subtribe Citrinae, — Citrus, For- 

 tunella, Microcitrus, Eremocitrus, Poncirus, and Citropsis. 



