1973] 
Scriber — Papilionidae 
359 
Bollow (1929), Fruhstorfer (1908), Jordan (1907, 1908-1909), 
von Rosen (1929), Seitz (1906), Stichel (1906), Shirozu (i960), 
D’Almeida (1966), and Common and Waterhouse (1972). 
The number of species known to occur in each ten degree latitude 
belt was recorded. The worldwide data were divided into the three 
geographical sections in figures 1, 2, and 3 to simplify the analysis. 
The components of each of these figures are shown in tabular form 
(Table 1). 
The species of known larval food-plants were compiled from the 
literature, although care was used in interpreting recorded host plant 
records (see Ehrlich and Raven, 1965; and Shields, Emmel, and 
Breedlove, 1969). The plant classification follows Willis (1973). 
A supplementary table with each species of Papilionidae with its 
latitudinal range, food-plant families fed upon, and citations for 
these food plant records is available from the author and at the 
following libraries: Cornell University (Entomology), Harvard 
(M.C.Z.), and the U.S.N.M. 1 
With those species feeding on more than one taxonomic family of 
plants as my “generalists” or wide-niche species, a species was counted 
in all parts of its range as being a wide-niche species, or generalist, 
if it feeds on more than one plant family anywhere in its range. 
Latitudinal gradients in niche breadth were prepared by enumer- 
ating the species for each ten degree belt of latitude and calculating 
the percentage of species exhibiting a “general” feeding strategy. 
Although the foodplants of the Papilionidae are probably as well 
known as those of any other taxon of similar magnitude, there are 
still gaps in the record. In the case of a species of unknown food- 
plant preference I have assumed that the host plant family range 
utilized is, in general, similar to those of closely related species of 
the group. There are, for example, many tropical Troidini for which 
the precise species of Aristolochia utilized are not known. 
Longitudinal and altitudinal variations in species richness are an 
important and interesting part of distributional patterns, but were: 
not considered in this study. 
Results 
Species richness is greatest in the tropical latitudes for each of the- 
three geographical regions (Figures 1, 2, 3). The significance of 
this trend for Papilionidae in the New World is discussed by Slansky 
The Grace Griswold Fund of the Department of Entomology of Cornell 
University assisted with the expense of having the supplementary tables of 
data copied. 
