
 
        
         
		THAUMATIAS   ALB I VENT RI S. 
 White-bellied  Emerald. 
 Trochilus tephrocephalus, Vieill. Nouv. Diet.  d’Hist.  Nat., tom. xxiii. p. 430.—lb .  Ency.  Méth. 
 Om.,  p a rt ii.  p.  560.—lb . Traité d’Orn.,  p. 283. 
 Omismya tephrocephalus,  Less. Hist. Nat.  des Ois. Mou., p. 182. pl. 62. 
 -------------albiventris, Less.  Hist. Nat.  des Ois. Mou., p.  209.  pl.  76.—lb .  Les  Troch.,  p.  94. 
 pi.  32.—lb . Traité d ’Ora., p.  283. 
 Polytmus  thaumatias,  Gray and Mitch. Gen. o f Birds, vol. i. p. 108, Polytmus, sp. 40. 
 Coeliyena  tephrocephala,  Reichenb.  Aufz.  der  Colibris,  p.  7.—lb .  Troch.  Enumer.,  p.  3. 
 dclxxxvii.  fig.  4518. 
 Aryytria  albiventi'is,  Reichenb. Troch.  enumer., p.  7. pi. d c c l v i i . figs. 4744,  4745.  
 Thaumatias albiventi'is, Bonap.  Consp.  Gen. Av.,  p. 78, Thaumatias, sp. 1. 
 Thaumantias albiventi'is, Bonap.  Rev.  e t Mag.  de Zool.  1854,  p.  255. 
 T his well-marked  species  differs  from  all  the  other  members of  its  genus  in  being of  a  larger  size  than  
 either of them,  and in having a greater amount of white on the abdomen  and  under  tail-coverts.  The two  
 sexes  are  so  much  alike  in outward appearance that  I  have  looked  in  vain  for  any decided difference  by  
 which  they may  be  distinguished;  I  observe,  however,  that  the female,  as  is  the  case  with  most  of  the  
 Humming Birds, is somewhat smaller and less pure in her colouring. 
 M. Bourcier  informs  me  that  this  bird inhabits  Santa Catharina,  in  Brazil,  and  remarks  that  it  bears a  
 great resemblance  to the  Thaumatias Linneei, but differs from  that species  in the larger size of its body, and  
 in the abdomen being always white in the adult. 
 M. Bourcier also tells me,  that the  specimen from which Vieillot  took his description  of tephrocephalus is  
 still  in  the  museum at  Paris,  but in a very bad state, with the feathers of  the  head  much worn and faded,  
 and  presenting  a  grey  appearance, which  doubtless  suggested the appellation Vieillot  assigned  to  it, and  
 which,  being  intended to express a feature that does not exist, must  give place  to that of albiventris, applied  
 to  it by M. Lesson. 
 Besides  Santa Catharina,  the northern parts of Brazil,  and the Delta of the Amazon, near its embouchure,  
 and the neighbouring country are frequented by this  bird. 
 Head,  all  the  upper  surface, wing- and  tail-coverts  dark green;  wings purplish-brown ;  two central  tail-  
 feathers  and  the  basal  portion  of  the  remainder dull  green,  the  extent of which decreases as  they recede  
 from  the centre,  middle  portion  of the  lateral feathers  Hackish-brown 5  the  tips brownish-grey,  increasing  
 in  extent as the feathers  recede from  the  centre ;  throat and chest shining grass-green;  flanks dull green;  
 abdomen and under tail-coverts white. 
 The figures  represent  the two  sexes of  the  size of  life.  The plant  is  copied from  a drawing sent to me  
 by Mr. Reeves.