474 PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 



29. Chimaera Colliei Bcunctt. 



29123 (91). $. Safety Cove, Brit. Col. Aug. 4, 1881. 

 Length, 19 iuches. 



30. Raia binoculata Girard. 



29805 (92). (Head.) Safety Cove, Brit. Col. Aug. 4, 1881. 

 29804(108). (Head.) Wraugel, Alaska. Aug. —, 1881. 

 Teeth of tirist, |^-; of second, \l. The second is a much larger indi- 

 vidual than the first. The first was caught in 10 lathoms. 



31. Squalus acanthias Liuu. 



29121 (79). <?. Brew's Harbor, Brit. Col. July 27, 1881. 



29122 (81). $. Menzie's Bay, Brit CoL July 31, 1881. 

 29120(101). 9. Red Bay, Alaska. Aug. 14, 1881. 



Length of 29121 is 2^ feet. No. 29122 is 2U inches long. 29120 is 

 29 inches long. The snout of the female is more obtuse than in the two 

 males. All of these specimens have a low keel along the lower margin 

 of the caudal peduncle from the end of the second dorsal to the root of 

 the caudal, just as in Atlantic specimens. 



These three dogfish were caught in 12, 5, and 12 fathoms, respectively. 



United States National Museum, 



January 31, 1882. 



ON THE RARE RODENT, CRICETODIPUS PARVVIS (BAIRD) COUE.*^. 



BY FREDERICK \». TRUE. 



At the time when Dr. Elliott Coues published his valuable mono- 

 graph of the Saccomyidse* the United States National Museum pos- 

 sessed but four specimens of the si^ecies Cricetodq)u,s jxcrvu.s Baird — two 

 of them in bad condition — including the single typesiiecinien of I'ro- 

 fessor Baird. On account of this scarcity of material he was forced to 

 si)eak very cautiously regarding the animal, leaving it uncertain whether 

 it was a distinct species or merely a variety of C. jiavus Baird. 



In an interesting collection of rodents in alcohol, recently received into 

 the Museum from Mr. Gustav Eisen, of Fresno, Cal., I found nine addi- 

 tional specimens of this doubtful species, seven of which are in j^erfect 

 condition. A careful examination of these has convinced me that (J. 

 jmrvus is a distinct species. The averages at the bottom of the follow- 

 ing table of measurements, com])ared with those given by Dr. Coues for 

 C. Jiavus,\ bring out, I think, very clearly the characteristic differences 

 of the two species. 



^ Coues. Eeport, U. S. Geol. Surv. of the Territories, xi, 1877. Monograph VIII, pp. 

 481-542. 



t Coues, 1. c, p. 518. 



