FRAGRANT BUTTERFLIES—CLARK 431 
sometimes makes the detection of the true male fragrance difficult 
and apparently explains much of the confusion in the records. 
Our spicebush swallowtail (Papilio troilus) is our most fragrant 
species. In this the males have a distinct and rather strong aroma 
difficult to describe, but exactly resembling that of Nabisco or Hunt- 
ley & Palmer’s honey biscuits. The odor of the female is not known. 
In the black swallowtail (P. polyzenes, fig. 34, pl. 6) the males have 
a rather strong, sweet odor like that of carrot flowers, quite the same, 
apparently, as that of the males of its close relative in Europe (P. 
machaon, fig. 37, pl. 6). No one has investigated the odor of the 
females. 
In our common yellow swallowtail (P. glaucus, fig. 45, pl. 9; figs. 
46, 47, pl. 10) the males, at least in Massachusetts, all have a sweet, 
flowery odor, varying from faint to fairly strong, which resembles 
that of the males of the spicebush swallowtail, though it is never so 
pronounced. The yellow females (fig. 46, pl. 10) have a strong and 
disagreeable odor, pungent or acid in quality, resembling rubber 
cement or creosote, which is very strong in some, especially in the 
South. The odor of the black females (fig. 47, pl. 10) has not been 
recorded. 
The males of the blue swallowtail (P. philenor) have a sweet 
flowery odor somewhat similar to that of the males of P. polyxenes, 
though not so strong. The females have a strong and disagreeable 
scent, pungent and penetrating, with a suggestion of acetic acid. 
Mr. William Schaus informs me that the most fragrant butterfly 
in his experience is P. devilliersi (fig. 40, pl. 8) which has been 
found in Florida, though properly confined to Cuba, a relative of 
our blue swallowtail. The odor is very strong and of a most pleasing 
nature, resembling that of the fragrant orchids. 
The male of the black and white swallowtail (P. marcellus, fig. 
' 52, pl. 11) has a very faint odor resembling that of the males of our 
other swallowtails, but with a spicy flavor not discernible in them. 
Fritz Miiller examined in Brazil the males of a swallowtail (P. 
polydamus) which ranges north to southern Florida and Texas. 
In these the odor was very strong. In this form there appear to be, 
indeed, two sets of males emitting equally strong but quite different 
odors, a condition aptly called by Mr. Scudder diosmism. In this 
same species (var. polycrates) Mr. Longstaff found an odor resem- 
bling that of musty hay in two examples of each sex; Mrs. Longstaff 
compared the scent to rue (Ruta gravolens). 
Several South American swallowtails were studied by Fritz Miil- 
ler. He found that the males of Papilio hyperion have a very strong 
odor; the males of P. scamander (?grayi) have a strong and most 
agreeable odor; the males of P. protesilaus (fig. 41, pl. 8) have a very 
strong rather disagreeable odor; and the males of P. nephalion have 
