66 MALDONADO. 



pears sti'ange tliat any animal should possess an 

 organ frequently subject to be injured. Lamarck 

 would have been delighted with this fact, had 

 he known it, when speculating* (probably with 

 more truth than usual with him) on the gradually- 

 acquired blindness of the Aspalax, a Gnawer living 

 under ground, and of the Proteus, a reptile living 

 in dark caverns filled with water ; in both of which 

 animals the eye is in an almost rudimentary state, 

 and is covered by a tendinous membrane and skin. 

 In the common mole the eye is extraordinarily 

 small but perfect, though luany anatomists doubt 

 whether it is connected with the true ojjtic nerve ; 

 its vision must certainly be imperfect, though prob- 

 ably useful to the animal when it leaves its bur- 

 row. In the tucutuco, wliirh I believe never comes 

 to the surface of the gi-ound, the eye is rather larger, 

 but often rendered blind and useless, though with- 

 out apjDarently causing any inconvenience to the 

 aniinal : no doubt Lamarck would have said that 

 the tucutuco is now passing into the state of the 

 Aspalax and Proteus. 



Birds of many kinds are extremely abundant on 

 the undulating grassy plains around Maldonado. 

 There are several species of a family allied in 

 structure and manners to our Starling : one of 

 these (Molothrus niger) is remarkable from its 

 habits. Several may often be seen standing to- 

 gether on the back of a cow or horse ; and while 

 perched on a hedge, pluming themselves in the 

 sun, they sometimes attempt to sing, or rather to 

 hiss ; the noise being very peculiar, resembling 

 that of bubbles of air passing rapidly from a small 

 orifice under water, so as to produce an acute 

 sound. According to Azara, this bird, like the cuc- 

 koo, deposits its eggs in other birds' nests. I was 

 * Philosoph. Zoolog., torn, i., p. 242, 



