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varies, the latter being especially common in the neck liga- 

 ments, whereas the former is reported by Piettre as not 

 invading that region. Neumann makes no reference to the 

 presence of his species in any other location, but there is 

 no evidence that it was looked for elsewhere. Piettre recorded 

 0. bovis as occurring in the femora-tibial (stifle) joint of 

 French cattle. The male of 0. bovis is much longer and the 

 female probably much shorter than those of 0. gutturosa. 

 The lengths of the male spicules, in the former, correspond 

 with those of Australian specimens, but are less than those 

 given by Neumann for 0. gutturosa. In our earlier account 

 it was mentioned that the female parasites were very like 

 those of the Algerian species, but that the dimensions of the 

 male spicules agreed with those of Piettre's species, hence 

 our earlier determination. It must be left for some other 

 investigator to determine whether Piettre's and Neumann's 

 species are distinct. 



The brief account (Joan, 1917) available regarding the 

 South American parasite allows one to note certain differ- 

 ences from the Australian species. The males in the former 

 are much longer and the papillae are said to be differently 

 arranged, but in view of the difficulty sometimes experienced 

 in detecting them, especially when the tail is closely rolled 

 up, and in view of the variations in position (especially 

 asymmetrical development) known to occur in the genus 

 Onchocerca, further examination might reveal additional 

 papillae. The South American female worms are recorded 

 as being much longer than the French 0. bovis, but agree 

 more nearly with Neumann's account. The maximum 

 diameter of the body and also the distance between the spirals 

 are given as being about twice as great as in Algerian and 

 Australian specimens. Besides, there are figured from six 

 to nine striae between the ridges, whereas in the other cases 

 there are from three to five. The egg is distinctly larger in 

 both diameters,' though not as large as given by Piettre for 

 those of the French species. 



It seems likely that the South American parasite is 

 not O. bovis, but the available description does not allow one 

 to synonymise it with 0. gutturosa. The lesions and site of 

 infection are similar to those of the Australian worm, as also are 

 those briefly described by Ransom (1920, 1921), who reported 

 that an Onchocerca occurred commonly in cattle slaughtered 

 in Chicago. Whether the latter is 0. gutturosa or the South 

 American species has not been settled, though Piettre recorded 

 as 0. bovis parasites collected from frozen beef from 

 Madagascar, Canada, and the United States. 



