AET. 1 ANCYLOSTOMA PLURIDENTATUM SCHWAETZ 7 



to note that the males of A. conepati, which have an average length 

 of 8.8 mm., have long spicules, their average size being 2 mm., the 

 ratio of the length of the spicules to the total length of the body 

 being practically the same in this species as in A. wucronatum. The 

 fact that both of these species occur in South America is of further 

 interest in connection with their possible identity. It may be noted, 

 however, that A. onucronatum is from an edentate, Dasypus gilvipes^ 

 whereas A. conepati is from a carnivore, Conepatus suffocans. 

 However, owing to the paucity of morphological data regarding 

 A. mua'onatuQn the question of the possible identity of this form 

 with A. conepati is left open. Both of these sjDecies appear to be 

 closely related to A. caninutn^ differing from the latter primarily in 

 the lengths of the spicules. Molin's figure of Diploodon quadriden- 

 tatum {=A mn/cetis) shows two pairs of well-developed teeth in the 

 anterior portion of the mouth capsule. Male specimens of this 

 species were not available to Molin, his description and figure being 

 based on a female. Whether this form, collected from a primate 

 {Mycetes coraya), is A. duodenale or whether it represents a dis- 

 tinct species can not be decided on the basis of Molin's description. 

 A. mini'muni is inadequately described, there being no reference to 

 teeth in the anterior portion of the buccal capsule. Von Linstow's 

 figure of the bursa suggests that the species may belong to the genus 

 Ancylostoma^ although the possibility that he was dealing with a 

 species of Uncinaria must also be taken into consideration. So far 

 as can be judged from the arrangement of the bursal rays, this 

 species is related to forms such as A. hraziliense and other species 

 of this genus, which have but two pairs of teeth in the anterior por- 

 tion of the buccal capsule. A. gilsoni Gedoelst, 1917, from Sciurus 

 prevosti^ is regarded by the writer as a synonym of A. hra- 

 ziliense, since the figures and measurements of this species given 

 by Gedoelst agree in practically all respects with available figures 

 and descriptions of A. hrazilieiise and with the writer's ob- 

 servations on that species based on a study of specimens from the 

 United States, South America, and various parts of Asia. Gedoelst 

 has apparently created A. gilsoni largely on the basis of host rela- 

 tionship and does not point out in what respects this species differs 

 from A. hraziliense. Our present knowledge of host relationships 

 of species of the genus Ancylostoma does not appear to justify the 

 erection of a new species on this basis alone, since certain species of 

 this genus are known to occur in aberrant hosts. This is especially 

 true with reference to A. hraziliense, which occurs not only in species 

 of carnivores but also occasionally in man, in which host it attains 

 fertile maturity. 



Lane (1916) has called attention to the fact that in species of the 

 genus Ancylostoma which contain three pairs of teeth in the anterior 



