276 
M. F. Pollen on the Genus Oxynotus. 
only on my visit to the Museum at the Royal College of Port 
Louis that I first had the pleasure of seeing one. 
Thanks to the kindness of Mr. Bouton, I had the opportunity 
of examining examples of the Mauritian Oxynotus, and of com¬ 
paring them with those of Reunion. I was then convinced that 
the remarks of the Editor of ‘ The Ibis ' were exact and correct. 
1 may here state that M. Jules Verreaux, in the “ Annexe ” to 
M. Maillard's ‘ Notes sur Pile de la Reunion'*, says (p. 162), 
“ Tuituit. Oxynotus ferrugineus, Sw. (Lanius ferrugineus, 
Gm.). Oiseau decrit sur la femelle, qui est rousse, le type 
venant de Pile Maurice ” ; and also remark that the Colonial 
Museum at St. Denis possesses a specimen of the Reunion bird, 
determined by this learned ornithologist to be a young male of 
O. ferrugineus , whereas I am now sure that it is an adult female 
of what I am about to describe as a new species; for, on com¬ 
paring examples of Oxynoti from the two islands, I find such 
differences of size and colouring between them as to lead me to 
believe that they do not belong to the same species; and when 
we know that these differences are constant, so that in Reunion 
an Oxynotus has never been found with the form and colour of 
that of Mauritius, nor in Mauritius has there ever been found an 
Oxynotus like that of Reunion, we must conclude that the birds 
of the one island are distinct from those of the other. 
The following Table shows the relative proportions of the 
birds of both islands :— 
Mauritius. Reunion. 
6 2 6 2 
Long, tot.175 mm. 190 mm. 177 mm. 177 mm. 
„ tarsi. 23 26 24 25 
„ dig. med. sine ungue 16 16 15 15 
„ mandib. sup. 30 28 20 20 
,, alse a carp.100 104 95 94 
„ caudse. 82 87 90 87 
From this it is apparent that the Mauritian Oxynotus exceeds 
that of Reunion in a majority of the above dimensions. 
The males of the Mauritian species have the upper part of the 
head, back, and rump of a dark smoke-grey, in immature (?) 
specimens slightly tinged with rufous. The chin and throat 
* [Cf. Ibis, 1863, pp. 103, 104.] 
