158 JOURNAL OF THE ARNOLD ARBORETUM (vol. ii 



Azalea L. sensu Desvaux 



Azalea Linnaeus, Spec, 150 (1753), quoad species 1-4. — Desvaux in 

 Jour. lioL Appl I. 35 (1813). — Roemer & Sdmltes, SysL iv. 374 (1819), 

 spec. 1^2 et 13 excluJ. — De Canclolle, Prodr. vii. 715 (1839). — Gray. 

 Man, 'ZGS (1848).— K. Koch, DcJidr, ii. 1, 171 (1872). — Brilton and 

 Brown, ///. Fl. ii. 559 (1897). — Relider in Bailey, Cycl Am, HorL i. 

 119 (1900). — Britten, 3/a/i. G98 (1901). — Small in iV. Am. FL xxix. 



41 (19U). 



TsuUusi Adanson, Fam. PL ii. 1G4 (17G3). 



Anthodendron Reichenbach in Moessler, Ilandh. GeinichsJc. i. 244, 308 

 (1827); FL Germ. Exc, 416 (1831). 



Though Azalea must be considered the oldest name for the genus as 

 shown by the synonomy and the remarks above, the name Loiseleurla 

 should be retained by those who follow the International Rules of Bo- 

 tanical Nomenclature, as it is one of the Nomina conservanda. If, how- 

 ever, a name is considered a nomcn conservandum in regard to the nomen 

 rejiciendum which in this case is Chamaecistus Oeder, one may main- 

 tain that Loiseleuria has preference only as far as it concerns Chamae- 

 cistus and that the introduction of an entirely new question of priority 

 alters the case which should then be decided according to the law of pri- 

 ority and without regard to the list of nomina conservanda. This opinion 

 is held by some botanists who are conscientious followers of the Inter- 

 national Rules and for an ex})osd of the reasons for this viewpoint I refer 

 to the remarks on the nomenclature of AVikstroemia Sclirad. by S. F. 

 Blake in the Contributions from the Gray Herbarium liii. 36. It seems, 

 however, to me that it is more advisable to consider the nomina con- 

 servanda, according to art. 20 of the Rules, names ''which must be retained 

 in all cases," or "en tons cas," as the original French text says, which 

 seems to express it even more strongly, as does also the Latin title of 

 the list which reads ''Indices nominum genericorum utique conservan- 



dorum." 



By those who consider the genus corresponding to Azalea of Desvaux 

 a distinct genus hicluding Rhodora, the latter name would be the correct 

 name of the whole genus, and Tsutsusi Adanson with Azalea indica as 



tvpe, if Rhodora is excluded, or Anthodendron Reichenbach with A. 



ponticum as type if Rhodora as well as Azalea indica are excluded. Brit- 

 ton and Small cite A. indica as type species of Azalea, but according to 

 Canon 15, b. and d. of the Philadelphia Code, the choice shouUl be be- 



tween .1. lapponica and A, procnmhens rather tlum a species which wa 



unknown to Linnaeus except from literature. 



The conclusion to be deduced from the preceding remarks may be 

 summed up as follows: 



Azalea Linnaeus is based chiefly on A, procnmhens which must be con- 

 sidered tlie type of the genus. 



According to the International Rules, Loiseleuria which also is based 

 on A. procumbens is a nomcn conservandum and tlierefore the name to 



