It) Georgina Stveet : 



marked range of variation in size in certain structures. The 

 almost certain derivation of the Australian Onchocerca gibsoni from 

 cattle imported from India or Malaysia, coupled with Dr. Leiper's 

 identification (1911, p. 10) of the parasite found by Ford in the 

 Mala} 7 States in 190-1 as 0. gibsoni, and the assertions of the same 

 identity in the case of the Javan parasite by other workers, made 

 one naturally expect to find the Indian species the same also. The 

 absolute similarity of the position and manner of occurrence of the 

 nodules in the body of the host and of their macroscopic structure 

 still further strengthened this expectation. However, during the 

 microscopic examination of one or two nodules as a matter of 

 routine identification, I was impressed by the variation shown by 

 them in some details of structure outside the range previously 

 recorded for 0. gibsoni, and accordingly dissected more nodules. 

 From these I obtained five females (four complete in essential parts} 

 and six complete males. 



Onchocerca gibsoni has been already described by Dr. Gilruth 

 and myself in detail in a Bulletin issued by the Commonwealth of 

 Australia, as well as by Drs. Cleland, Johnston, Leiper and Breinl 

 (see Bibliography). After careful measurements and comparisons 

 with this and other forms, I have been forced to the conclusion that 

 the form found in cattle in India is to be regarded as a different 

 species, which I have called 0. iiidica, and a specific description of 

 which is hereafter given ; nevertheless I have no doubt whatever as 

 to the origin of these forms from one another, or else of both from 

 a common ancestral form. In view of this it is doubly disappoint- 

 ing to me not to have yet received other material from Javan and 

 Egyptian cattle and buffaloes, and also from Malaysian and Indian 

 buffaloes 1 as this (especially that from Javan cattle) would prob- 

 ably throw further light on the question. Nevertheless it seems- 

 desirable to publish what I can up to date, and add to it later on. 

 I have a certain amount of material from some of these hosts and 

 localities, but, as previously stated, it was in such a condition as to 

 be useless for this purpose. While this report was being completed 

 I had the gratification of receiving specimens from Mr. Ford from 

 an Indian bullock in Malaysia, and from Siain cattle, which will 

 he referred to later. 2 The nodules found in cattle (Bos indicus) in 

 India resemble exactly in macroscopic appearance and position in 

 the body those of 0. gibsoni found in cattle (Bos taurus) in Aus- 



1 See Addendum 1. re <>. indiea in Bos bubalis. 



2 see Addendum l, re 0. indiea in Bos bubalis. 



