Geographical Races q/Lutreolina crassicaudata. 585 



occur all tlie way down the river, so that tiiere is no gap 

 which might indicate a specific separation between crassi- 

 caudafa and paranalis. 



Type, Adult female. B.M. no. 17. 5. 2. 22. Original 

 number 2770. Collected 6th November, 19] 6, by Robin 

 Kemp. Presented by Oldfield Thomas. Twelve specimens. 



4. L. c. honaria^ subsp. n. 



Size averaging even slightly larger than in paranalis^ 

 and similarly equal in the two sexes. General colour paler, 

 more yellowish buff}^ Under surface also paler. 



Dimensions of the type (tneasured in the flesh) : — 



Head and body 350 mm. ; tail 305 ; hind foot 47 ; ear 28. 



Skull : greatest length 67 ; combined length of ms^'"^ 10'9. 



Other skulls measure : cT 75, $ 76, 64. 



Hah. Buenos Ayres Province, froui the neighbourhood of 

 Buenos Ayres (Belgrano) to Cape San Antonio ; type from 

 Los Yngleses, Ajo. 



Type. Adult female. B.M. no. 20. 2. 7. 44. Original 

 number 21. Collected 20th July, 1919, by H. E. Box, 

 and preserited by Oldfield Thomas. Eight specimens. 



The greater pallor of these southern Lutreolines is very 

 evident on the comparison of a series of them with those of 

 Santa Fe, representative of Z. c. paranalis^ though indi- 

 vidually the difference is not very striking. 



5. Tj. c. lutrilla, subsp. n. 



Size decidedly less than in any other of the southern forms, 

 the male just equalling, and the female barely exceeding, the 

 corresponding sexes of the little British Guiana subspecies. 

 Colour at present indeterminable, as Darwin's specimen is 

 apparently bleached, and the Rio Giande do Sul one is in 

 spirit, but the general tone is probably about as in paranalis. 



Dimensions of the type (measured on a skin preserved in 

 spirit) : — 



Tail 230 mm. ; hind foot 32 ; ear 20. 



Skull: greatest length 58; combined length of ms^~^ 9*4. 



Greatest length of male skull 60. 



Hah. Hio Grande do Sul and S.E. Uruguay. Type from 

 San Lorenzo, R. Grande do Sul. 



Type, Adult female, skin in alcohol. B.M. no. 85. 6. 

 26. 2t). Collected by Dr. H. von Ihering. 



Darwin's specimen from Maldonado, figured in the "Voyage 

 of the 'Beagle,'" would appear to be the same form, which 

 is distinguished by its very small size. 



Ann. & Mag. N. Hist. Ser. 9. Vol. xi. 38 



