16<) MR. P. L. SCLATElv OX A RARE ARGENTINE KIKl). [Jan. 17, 



I lm\e uimh liesitiitiun in separating this species from C 

 orientafis, Uljaiiin, from which it differs chiefly in the proportions 

 of the abdominal segments, in the size of the third free thoracic 

 segment, which is larger than in C. orientaUs, and in the size of the 

 fused head ai.d first thoracis segment, which in C. ot-ientalis is 

 equal in length to the four free thoracic segments and the first 

 abdominal segment, while in C. afncamcs it is much shorter. I 

 have not been able to find a female carrying ova, but the specimen 

 from which the description is taken had its ovaries full of ripe ova. 



The single male specimen I found ^\as apparently mature. It 

 differs markedly in the jointing and in the proportions of the 

 antennae from Uljanin's figure, \Ahich is very probably taken from 

 an immature specimen. 



EXPLANATION OF PLATE VI. 



Canthocampiusjinni, p. 164. 



Fig. 1. Lateral view of female. 



2. First antenna of female. 



3. Second antenna. 



4. Mandible. 



5.. First swimming-foot, 

 (i. Fourth swittming-foot. 

 7. Fifth foot of female. 



Cyclops africamis, p. K55. 

 Fig. 8. Female, viewed from above. 

 9. First antenna of female. 



10. First antenna of male. 



11. Fifth foot. 



4, Remarks on a rare Argentine Bircl^ Xenopsaris albinucha. 

 By P. L. ScLAT£R, M.A., Ph.D., F.R.S., Secretary to 

 the Society. 



[Keceived December 22, 1892.] 



(Plate VII.) 



In 1S68 our late distinguished Foreign Member, Dr. H. Bur- 

 meister, of Buenos Ayres, described, in a communication to this 

 Society on additions to the Argentine Avifauna, a small Passerine 

 bird of which he had obtained specimens in the sedge of the shores 

 of the Eio de la Plata, near Buenos Ayres, under the name of 

 Paclnirliamplius alhimtcha. Xo specimen accompanied this com- 

 munication, and the subject appears to have been until quite recently 

 overlooked by subsequent writers. Although the title of the paper 

 was given by Mr. Hudson and myself in the Appendix to our 

 'Argentine Ornithology' {op. cit. ii. p. 222), and it is there re- 

 corded that Pcuhijrhamplnis idbinucha was described as new, the 

 species was unfortunately forgotten in the body of that work. The 

 same was the case, I regret to say, in the fourteenth volume of the 



