of D. candida which is also unique to the same locality. 
Other observers of M. Amesianum have associated it 
with the tree Daturas. Theilkuhl (14) related it to the 
other diseased and curiously malformed Datura clones 
in the Valley of Sibundoy, while Barclay (8) suggested 
it could be, ‘‘the result of the action of a single pleio- 
tropic gene mutation... . a monstrosity of some Da- 
tura species of subg. Brugmansia... .’’ Van Steenis 
(18) in discussing genotypic variability at the infraspecific 
level, cited M. Amesianum as, ‘‘a remarkable case of 
adesmy. a tendency which is recorded from various 
Solanaceae. ”* 
SPECIMENS EXAMINED: 
Cotometa: Bristol 477, 764, 888, 1112, 1391, 1400; Fernandes 2641; 
Fosberg 20406; Idrobo 2221; Mora 1023; Olday 689; Schultes 3256; 
Schultes & Cabrera 20079 (Tyee; GH); Villarreal 68. 
Abnormalities suggestive of M. Amesianum have ap- 
peared in several species of Datura. Barclay (8) noted 
the deeply divided, spatulate-lobed corollas occurring in 
D. inowta Miller (Davidson 1659; GH) and in D. ferox 
L. (Venturi 328; A). The most extreme modification is 
the highly adesmic ‘‘equisetum”’ form of D. Stramonium 
L. (Moldenke & Moldenke 11814; NY). This single re- 
cessive gene (1) causes nearly filiform leaves and both 
the calyx and corolla are divided almost to the base, the 
corolla appearing merely as filiform segments. In addi- 
tion to the five stamens, there are at least six staminodia. 
Another D. Stramonium mutant, ‘‘quercina’’, also has 
a divided corolla and modified leaves and fruits (1). A 
collection (Romero-C. 5364; COL) from the Pacific coast 
of southernmost Colombia is similar to M. Amesianum 
but differs in the long-lanceolate leaves (as in D. longi- 
folia), in the extension of the calyx tip into five distinct, 
long (7.5 em.) subulate apices, and in the short (14 em.) 
[ 245 ] 
