68 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



for catching surface water, which never go dry, and which have no regular supply or 

 discharge of water. Lake Nahuel Huapi is the largest of a chain of lakes in the 

 Andes Mountains, which may be called the sources of the Rio Limay. These are 

 found in latitude 38J° to 4l2° south. Lake Nahuel Huapi is almost on the Chilean 

 border, the dividing line being a series of steeple-shaped peaks which are snow-clad 

 throughout the year. Its elevation is about 2,500 feet. The waters are very clear 

 and one can see to a dej^th of about 20 or 30 feet. The shore line is very irregular, 

 and only a very small i^art of the lake can be seen at any one time by a boatman on 

 it. Tliere are several islands in the lake one of which contains a small pond of ab<iut 

 15 or 20 acres in area. The lake is fed by innumeraljle small streams, and several 

 quite large ones. Lake Traful is about 2,300 feet elevation, and is much smaller than 

 Lake Nahuel Huapi. It covers perhaps one-tenth of the area of the larger lake. It 

 is probably about 10 miles long and 2 miles wide at its widest point. It is surrounded 

 by mountains, and the shore line is precipitous, so much so that in many places it is 

 impossible to make a landing from the lake. This lake is apparently very deep, and 

 its waters are clear and cold, similar to those of Lake Nahuel Huapi. V^arious 

 other lakes in the same district mentioned above were reported to be similar in char- 

 acter. Some of them are larger than Lake Traful. Lake Nahuel Huapi reminds 

 one very much of Lake Winnepesaukee. It is quite as irregular, has clearer water 

 of a lower temperature, and not nearly so many islands. It must be very deep in 

 some parts. The shores rise abruptly several hundred feet in places. 



The nature of the waters of the Limay River may be judged pretty accurately from 

 the description of Lakes Nahuel Huapi and Traful. These and many other lakes in 

 the Andes flowing into the river cause it at times to overflow its banks and spread 

 over quite a large territory. At the outlet of Nahuel Huapi, which may properly be 

 called the source of the Lhnay, the lake itself rises 15 or 20 feet. When the river is 

 at its normal height it is in places only 200 or 300 yards wide, but quite deep. In 

 other places it is a mile wide. In many places there are rapids dangerous to navi- 

 gation in small boats. Owing to the fact that the river spreads out in width so fre- 

 quently, and also because it breaks up in small channels, it can not be called navigable 

 for any but small boats. 



We are indebted to Dr. Carl H. Eigenmann, of Indiana Universit}^, 

 for assistance in the identification of the C^^haracins. 



Family GALEID^E. 



I. MUSTELUS CANIS (Mitchill). 

 TIBURON; CAZ6n. 



Squalus canis Mitchill, Trans. Lit. and Philos. Soc. New York, I, 1815, p. 486, 



New York. 

 3 fustelus vulgaris, GtJNTHER, Ann. Mag. Nat. Hist., 5th ser.. No. 3, July, 1880, p. 7. 

 Galeus canis, Berg, Anal. Mus. Nac. Buenos Aires, IV" (2d ser., I), 1895, p. 7 



(Bahia Blanca; Mar del Plata; Montevideo; Rio de la Plata). 



Berg says that this species is rather common on the coast and ascends 

 the Rio de la Plata almost to fresh water. 



We have 4 specimens, all males, measuring from 17.25 to 22.75 

 inches total length. 



