238 



female is not represented. A few tiny papillae appear to be 

 present at a little distance behind the mouth. Cuticular 

 ornamentation is hardly recognizable even under the oil 

 immersion. The cuticle is very delicate, measuring about 

 25 to 3 jul in thickness. 



The anterior end (figs. 4, 13) resembles that of the female, 

 as also does the oesophagus, which has a similar diameter 

 (10 to 12 /a), but the length is -82 to 1*1 mm. The anus 

 lies at -075 to -085 mm. from the tip of the spirally coiled tail. 

 The male papillary arrangement is usually as follows 

 (fig. 10) : four pair of perianal, of which the third pair are 

 often rather smaller than the others; a post anal group of 

 two, consisting of a smaller anterior papilla, lying just in 

 front of, or beside, a larger one; and a caudal group composed 

 of a prominent double one formed by the fusion of the pair 

 (i.e., one from each side), and there may, at times, be recog- 

 nized a very small papilla on each side in front of it. The 

 alae are rather narrow. 



The longer spicule has an obliquely pointed end and 

 measures from *180 to *255 /x in length, the breadth being 

 5 to 7 /a, while the shorter spicule is a thicker organ termin- 

 ating in an enlarged rounded extremity. The shorter 

 measures *060 to '080 mm. (generally about *070) in length 

 and 7 to 10 jul in maximum breadth (excluding the anterior 

 expanded rim-like portion), its form tapering posteriorly so 

 that the width is about 3 jul just in front of the widened 

 extremity, which is about 5 // across and 10 jut long (fig. 20). 



If the information relating to this Australian species 

 and 0. gutturosa from Northern Africa, contained in the 

 accompanying tables be compared, it will be noticed in regard 

 to the males, that practically all the measurements agree 

 except the lengths of the greater spicule, Neumann's maxi- 

 mum being longer than our maximum. In the case of the 

 females the agreement is practically complete, the only 

 marked differences being in regard to the diameters of the 

 oesophagus and the cervical dilatation, these being of minor 

 importance. It seems best to regard the Australian para- 

 sites as 0. gutturosa, including under its synonymy 0. bovis, 

 Johnston and Bancroft, 1920 (nee Piettre, 1912). A speci- 

 men collected from an ox in Sydney Abattoirs and placed 

 at our disposal through the kindness of Dr. E. W. Ferguson, 

 Health Department, Sydney, was found to be specifically 

 identical with the Queensland material. 



The information available to the writer regarding O. 

 bovis, Piettre, from French cattle is not sufficient to allow 

 him to compare it with O. gutturosa. The site of infection 



