TITHYMOLOPSIS AND DICHROPHYLLUM 299 
names are noted in the Kew Index, and should therefore have 
come up for consideration when the genera were taken up. 
Rafinesque’s Agaloma antedates Klotzsch and Garcke’s 
Tithymalopsis by a score of years. Moreover, there is little room 
for quibbling about the identity of the names as the author, though 
admitting a considerable number of species to the genus, clearly 
points out which plant is the type of his new group. He says: 
“Agaloma corollata R. Euph. do. O. type of the G.’’ Any group 
of corelated species segregated form the Linnaean Euphorbia, 
and containing Euphorbia corollata Linn. ought to be included 
under Rafinesque’s name. 
Klotzsch and Garcke’s Dichrophyllum is likewise preceded 
by Rafinesque’s Lepadena,* under which he quotes Euphorbia’ 
marginata Pursh. In the same pages of revision of Euphorbia 
Rafinesque protests that the then recently published Povnsettia 
Graham (1836) was anticipated in 1833 by his own Pleuradena, 
though he had in 1825 made another Pleuradenia (=Collinsonia 
sp.). Graham’s name enjoys validilty therefore for this third genus. 
Following is the synonymy of the genera with some of the 
transferred species. 
Acatoma Raf. Fl. Tell. p. 94 (1836). 
Tithymalopsis Klotzsch & Garcke, Monatsb. Acad. Berl. 
(249 (1859). 
Euphorbia Linn. Sp. Pl. 450. (1753) pro parte. 
Agaloma corollata Raf. do. p. 95. 
Tithymalopsts corollata Kl. & Garcke. 1. c. 
Euphorbia corollata Linn., Sp. Pl. p. 459 (1753). 
Agaloma polyphylla (Engelm.) 
Tithymalopsis polyphylla (Engelm.) Small 1. c. Fl. S. E. U.S. 
p. 716 (1903). 
Euphorbia polyphylla Engelm. 
Agaloma gracilis (Ell.) 
Tithymalopsis gracilis (Ell.) Small. 1. ¢. 
Agaloma eriogonoides (Small). 
Tithymalus errogonoides Small. 1. c. 
Euphorbia eriogonoides Small. 
Agaloma mercurialina (Michx.) 
Tithymalopsis mercurialina (Michx.) Small, 1. c. 
Euphorbia mercurialina Michx. 
