102 MR. W. H. HUDSON ON THE HABITS OF RAILS. [Jail. 18, 



4. Notes on the Rails of the Argentine Republic. 

 By W. H. Hudson, C.M.Z.S. 



[Eeceived December 19, 1875.] 



The Carau or Courlan (Aramus scolopaceus) has been called " an 

 abnormal relative of the Rails at the most;" but in habits and 

 appearance it is certainly near akin to them. 



The beak of this bird is nearly 5 inches long, straight, and of an 

 iron hardness ; the tip is slightly bent to one side, the lower man- 

 dible somewhat more than the upper. The tongue extends to the 

 extremity of the beak ; at the end it is of a horny toughness, and 

 frayed or split into filaments. This beak is a most effective instru- 

 ment in opening shells ; for where mollusks abound the Courlan sub- 

 sists exclusively on them, so that the margins of the streams which 

 this bird frequents are strewn with innumerable shells lying open and 

 emptied of their contents. 



Every shell has an angular piece, half an inch long, broken from 

 the edge of one valve. Mussels and clams close their shells so 

 tightly that it would perhaps be impossible for a bird to insert his 

 beak, however knife-like in shape and hardness, between the valves 

 in order to force them open ; therefore I believe the Aramus first 

 feels the shell with his foot whilst, wading, then with quick dexterity 

 strikes his beak into it before it closes, and so conveys it to the shore. 

 It would be most difficult for the bird to lift the closed shell from 

 the water and carry it to land ; but supposing it could do this, and 

 afterwards succeeded in drilling a hole through it with its beak, the 

 hole thus made would have jagged edges, and be irregular in shape ; 

 but it is, as I have said, angular and with a clean edge, showing that 

 the bird had just thrust his beak half an inch or an inch between 

 the valves, then forced them open, breaking the piece out during the 

 process, and probably keeping the shell steady by pressing on it with 

 the feet. 



By day the Aramus is a dull bird, concealing itself in dense reed- 

 beds in streams and marshes. When driven up he rises laboriously, 

 the legs dangling down, and inounts vertically to a considerable 

 height. lie flies high, the wings curved upward and violently 

 flapped at irregular intervals ; descending, he drops suddenly to the 

 earth, the wings motionless, pointing up, and the body swaying 

 from side to side, so that the bird presents the appearance of a Jail- 

 ing parachute. On smooth ground he walks faster than a man, 

 striking out his feet in a stately manner and jerking the tail, and 

 runs rapidly ten or twelve yards before rising. At the approach of 

 night he becomes active, uttering long clear piercing cries many 

 times repeated, and heard distinctly two miles away. These cries 

 are most melancholy, and, together with its mourning plumage and 

 recluse habits, have won for the Aramus several pretty vernacular 

 names. He is called the "Lamenting Bird" and the "Crazy 

 Widow," but is more familiarly known as the "Carau." 



Near sunset the Caraus leave the reed-beds and begin to ascend 



