20 
Psyche 
[March-June 
while some species of Parides undoubtedly lay eggs singly and 
Ornithoptera lays eggs singly. It is suggested that there may exist 
phylogenetic differences in oviposition patterns at the generic level 
in the Troidini, and that secondary differences in these patterns are 
molded by contemporary ecological factors. 
Acknowledgements 
The La Selva portion of these studies was financed by N.S.F. 
Grant GB-7805, Daniel H. Janzen, principal investigator, with 
logistic support through the Organization for Tropical Studies, Inc. 
The Tirimbina studies were financed by Grant No. 12 1 of the 
Bache Fund of the National Academy of Science and partially by 
N.S.F. Grant GB-33060. Logistic support was provided by the 
Costa Rican program of the Associated Colleges of the Midwest. 
Roger Kimber and John Thomason assisted with rearing and food 
plant acceptance studies. Howard W. Pfeifer identified the species 
of Aristolochia and provided rooted cuttings of several species. Lee 
D. Miller confirmed the identification of the butterfly. The manu- 
script was read by Murray S. Blum. 
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