No. 555] SPECIES-FORMING OF ECTO-P ABASHES Uo 



or three or four— the maximum is actually six— Mallo- 

 phagan species are found on a single host species. The 

 great bulk of the parasitization comes from compara- 

 tively few Mallophagan species, notably the three spe- 

 cies already named. 



The Pelecaniformes, 75 living species, including the 

 pelicans, cormorants, boobies, man-o'-war and tropic 

 birds, are represented in the host list by thirty-three spe- 

 cies. Thirteen of these are cormorants of the genus 

 Phalacrocorax, and nine are boobies of the genus Sula. 

 Lipeurus setosus occurs on two African and two Aus- 

 tralian and Malaysian species of Phalacrocorax. Lipeu- 

 rus toxoceros occurs on one cosmopolitan cormorant and 

 on two others, one of South and Central America and 

 one of North America. Lipeurus faralloni is recorded 

 from three North American west coast species. Five 

 species of Pelecanus, three new world and two old world, 

 are included in the list. Menopon titan occurs on two 

 of the new world and one of the old world species, Lipeu- 

 rus bifasciatus on one new world and both of the old 

 world forms, and Li paints for/iculatus on two new world 

 and one old world species. Eleven species of Mallophaga 

 are recorded from the cosmopolitan man-o'-war bird, 

 Fregata aquila, and eight from the beautiful white tropic 

 bird, Phaeton cethereus. 



The Cathartidiformes, or new world vultures, are rep- 

 resented in the host list by four species. There are but 

 nine species in the order. The four species in my list 

 are the great condor of the Andes, ranging from Pata- 

 gonia to Ecuador; the great king vulture of the northern 

 Andes, Central America and Mexico; the rare Cali- 

 fornian condor of northern Mexico, Baja California, and 

 California north to its middle region; and finally, the 

 ubiquitous turkey vulture, smaller and far more abun- 

 dant than any of the others, that ranges over all of North 

 America and, in winter, gets into northern South Amer- 

 ica. Thus the ranges of the four species combined ex- 

 tend the whole length of the western coast of the new 



