—Cogniaux in Martius Fl. Bras. 8, pt. 4 (1893) 110, t. 
21, fig. IIT. 
Dr. Bernardo Rosengurtt has sent to me a good 
specimen of this rare plant for determination and it calls 
to attention the differences from Bipinnula Gibertu 
Reichb.f. which I thought it was at first glance. 
The chief character used by AKrdnzlin to separate Bi- 
pinnula polysyka from B. Giberti in his key, the den- 
tate or papillose dorsal sepal, is slightly evident on only 
one of the plants available whereas on all of the others 
the dorsal sepal is entire. However, the two ‘“‘species”’ 
may be separated by means of lip-characters, although a 
more complete series of specimens may show B.polysyka 
Kriinzl. to be only a variety of B.Gibertw Reichb.f. 
Urvuauay: dry sandy fields, Cerro, Departmento de Montevideo, 
November 1925, Herter 442b (79697) (in Gray Herbarium); Monzén- 
Heber, Juan Jackson, Departmento Soriano, noviembre 1937, Gal- 
linal, Aragone, Bergalli, Campal & Rosengurtt 779; Palleros, Rio Negro, 
Departmento Cerro Largo, diciembre 1937, Gallinal et al 1897. 
Erythrodes dichopetala ( Kriinz/. ) L.O. Willams 
comb. nov. 
Physurus dichopetalus Kriinzlin in Kungl. Svenska 
Vet.-Akad. Handl. 46 (1911) 41, t. 7, fig. 5. 
I have seen the following specimen: 
Arcentina: Posadas, Misiones, January 10, 1924, Hauman 24 / 
476. 
Malaxis Margaretae (I. Brown) L. O. Williams 
comb. nov. 
Microstylis Margaretae F. Brown in B. P. Bishop 
Mus. Bull. 84 (1931) 171, fig. 18, b. 
Austra. Istanvs: Stokes 105. 
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