822 MR. W. H. HUDSON ON THE [NoV. 1 9, 



of a bright red colour ; and there is no reduction of their number, nor 

 in their size, at the csecal end at all. At the lacerated extremity, close 

 to the rupture they are paler and more scattered. The walls of 

 the viscus are of uniform thickness, except for a few inches round 

 the point of attachment of the cord, where the vessels commence to 

 diffuse themselves. 



When received, the whole sac was turned inside out ; and this was 

 probably the result of the gradual contraction of the uterus from 

 fundus to orifice. It may be remarked that for a few days after the 

 birth of the calf, the mother had a considerable prolapse of the 

 vagina, which gradually diminished, and is now very slight. 



3. On the Habits of the Vizcacha (Lagostamus trichodactylus) . 

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



[Eeceived September 10, 1872.] 



The Vizcachas in the pampas of Buenos Ayres live in societies, 

 usually numbering twenty or thirty members. The village (called 

 here " Vizcachera") is composed of a dozen or fifteen burrows or 

 mouths ; for one entrance often serves for two or more distinct holes. 

 Often, where the ground is soft, there are twenty or thirty or more 

 burrows iu an old vizcachera ; but on stony, or " tosca," soil even an 

 old one may have no more than four or five burrows. They are deep 

 wide-mouthed holes, placed very close together, the entire village 

 covering an area of from 100 to 200 square feet of ground. 



The burrows vary greatly in extent ; and usually in a vizcachera 

 there are several that, at a distance of from 4 to 6 feet from the en- 

 trance, open into large circular chambers. From these chambers 

 other burrows diverge in all directions, some running horizontally, 

 others obliquely downwards to a maximum depth of b' feet from the 

 surface : some of these burrows or galleries communicate with those 

 of other burrows. A vast amount of loose earth is thus brought up, 

 and forms a very irregular mound, 15 to 30 inches above the sur- 

 rounding level. 



It will afford some conception of the numbers of these vizcacheras 

 on the settled pampas when I say that, in some directions, a person 

 might ride 500 miles and never advance half a mile without seeing 

 one or more of them. In districts where, as far as the eye can see, 

 the plains are as level and smooth as a bowling-green, especially in 

 winter when the grass is close-cropped, and where the rough giant- 

 thistle has not sprung up, these mounds appear like brown or dark 

 spots on a green surface. They are the only irregularities that occur 

 to catch the eye, and consequently form an important feature iu the 

 scenery. In some places they are so near together that a person on 

 horseback might count a hundred of them from one point of view. 



The sites of which the Vizcacha invariably makes choice to work 

 on, as well as his manner of burrowing, adapt him peculiarly to live 

 and thrive on the open pampas. Other burrowing species seem 



