Filaria lua 27 



this region disclosed the four pairs of large circumanal papillae" 

 characteristic of Filaria loa. One important feature was noted 

 in this connection. These papillae do not constitute four bilateral 

 pairs, but rather a left and a right series of four each, in which 

 the individual papillae alternate with each other, those of the left 

 side being the more anterior, while those on the right are more 

 closely crowded together. The anterior papilla is also the largest 

 in each series, and the size decreases regularly posteriad. 



This asymmetrical arrangement originally described by Looss 

 is not an abnormality in the specimen he studied, and I can con- 

 firm his view that it is a general characteristic. At least it is 

 actually present in the three males I examined and will no doubt 

 be found on more extended examination to be universal. 



Posterior to these large papillae lie, first, a symmetrical pair 

 of small papillae and then, almost at the tip of the body accord- 

 ing to Looss, a minute pair, also symmetrically placed. The 

 latter I was unable to find. 



In the specimen received from Dr. Loveland, the spicules could 

 be most clearly seen; their length was 104//- and iSo/x, measure- 

 ments which accord closely with those given by Looss. Further 

 than this my observations, though in some respects less complete, 

 merely confirm the anatomical description given by Looss. It is 

 important to call attention to the results of a comparison of 

 measurements. of F. loa given by various authors, and since only 

 relatively few have given sufficient data for the determination of 

 the sex of the parasites, the figures available are much more 

 limited than the number of cases. 



According to various records the measured length of the male 

 is 22 mm. (Blanchard), 23 mm. (Looss). 25 to 30 mm. (Man- 

 son), 30 and 35 mm. (Ozzard), and 16, 22, and 25 mm. (Ward). 

 It is noteworthy that the female varies more widely: among the 

 measurements given are 20 mm. (Blanchard), 50 mm. (Annett, 

 Button, and Elliott), 52 mm. (Looss), 27 mm. (Lueckart), 41 

 mm. (Ludwig), 32.5 mm. (Manson), 50 and 55 mm. (Ozzard). 

 Blanchard notes that his specimen was still young, and yet even 

 that of Looss was far from having attained the size of Maurel's 

 specimen, which measured 70 mm. and which from its extreme 



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