60 



SCIEJSrCJE. 



[Vol. IX., No 207 



only for the dogs to run out upon it at night, but 

 the coyotes, long since accustomed to the sight of 

 the pueblo and all that is in it, to approach with less 

 suspicion than they would even about an Indian 

 camp. Moreover, some of these Zunian dogs have 

 very much the appearance and behavior of the 

 coyotes themselves, and quite as much cunning in 

 some instances. Among the rarer varieties of the 

 former we sometimes find a sheep-dog of apparently 

 the same breed of animal often seen in certain parts 

 of the eastern states. I refer to the black-and-tan 

 variety, with the shaggy coat, and the tan-spots, one 

 over each eye. The trader at Ziini, an observing 

 and intelligent Englishman, has long owned one of 

 this latter kind, — a bitch of excellent qualities, — 

 and it is from this gentleman that I came into pos- 

 session of the following account. He tells me that a 

 little over three and a half years ago, the oppor- 

 tunity was afforded him to become jiersonally cog- 

 nizant of the fact that this shepherd-dog bitch of his 

 was lined by a large male coyotfe one evening just 

 beyond the limits of the pueblo. In due time she 

 gave birth to four male pups, that looked curiously 

 Tike young coyotes from the hour they were 

 born. "When I came to Wingate here, all four 

 of these dogs were fully grown, and were owned 

 by different parties at the garrison, and I had ex- 

 cellent opportunities to study them. They all 

 very much resembled each other, and the entire 

 progeny are the very exemplification of what we 

 might easily imagine the offspring of such a parent- 

 age would be. Taking any one of them as an 

 example, it is to be noted that the animal has a 

 form somewhat heavier than a coyote, and yet 

 more slender and agile than a shepherd-dog. As 

 we would naturally expect, its pelage is rather long 

 and shaggy, with a handsome flag to its tail. In 

 color it is a fine stone gray, inclining to blackish on 

 the flanks and sides ; the spots are absent from over 

 the eyes. The ears have more of the form of the 

 coyote's than they have of the ears of the mother ; 

 while the fore part of the face, and the muzzle, more 

 nearly approach that of a shepherd-dog. One of the 

 most interesting features of it all is to hear one of 

 them bark ; for those who may be familiar with the 

 despicable howl of the prairie-wolf can here have the 

 opportunity to fully appreciate how much that kind 

 of music can be improved by being semi-modified by 

 siich crossing in stock. The yelp becomes softened, 

 and the more intelligent expressions of the bark are 

 introduced, though in the present case these seem 

 to be about equally divided in the voices of these 

 hybrids. 



When out of the garrison, I have observed much 

 in their behavior that reminds me of the coyote, 

 more than it does of the dog. They run and trot 

 like a coyote ; and when off at a distance they have 

 a way of standing sidewise as motionless as a statue, 

 and regarding you ; while at such times they keep 

 their two fore-limbs together, as well as the hinder 

 ones. Such a position is very commonly assumed by 

 the prairie-wolf, and may be said to be a direct 

 lateral view of the animal, with its face looking to- 

 wards you. 



Space will not permit me to enter upon the many 

 little interesting traits of these animals, which plain- 

 ly are due to the crossing of the parent stock, and 

 have been inherited by the issue. 



It is my present aim to purchase one of these 

 animals, if possible, with the view of securing its 



skeleton, more especially its skull. This latter 

 would undoubtedly make an interesting thing to 

 compare with Huxley's valuable work on the skulls 

 of the Canidae. I have collected a fine series of the 

 skulls of the coyotes, and have them in my possession 

 at the present writing. E. W. Shtjfeldt. 



Fort Wingate, N. Max., Jan. 11. 



To authors of text-books on physics. 



The definition of the coefficient of elasticity, 

 given by Professor Baker on p. 34 of the current vol- 

 ume, is vitally defective because the unit of section 

 is omitted. It reads, ' ' The coefficient of elasticity 

 may be defined as the force which would double tlie 

 length of a bar." According to this, if the section 

 of one bar were twice that of another, all other 

 things being equal, the coefficient of elasticity of 

 the former would be double that of the latter, which 

 is not true. A student might further object that 

 solids cannot be elongated to double their length, 

 nor liquids be compressed to half their volume, or, 

 if they could, the coefficient would not remain con- 

 stant during the operation. Strictly speaking, the 

 coefficient of elasticity is a rate, and may be de- 

 fined as the rate of change of the stress per unit of 

 section to that of the elongation per unit of length. 

 This is true for the incipient elongation due to an 

 incipient stress. If it be assumed that the section 

 of the bar remains uniform and the elasticity remains 

 perfect during the elongation, then it will be true 

 that the coefficient of elasticity equals the force 

 which would double the length of a bar whose cross- 

 section is unity. DeVolson Wood. 



Hoboken, N.J., Jan. 15. 



H. Allyne Nicholson. 



In answer to a letter of condolence written in con- 

 sequence of the press despatches announcing the 

 death of Prof. H. Allyne Nicholson, Dr. C. A. White 

 has received a letter from Professor Nicholson him- 

 self, saying that he is not dead, but alive and well. 



If the above has not been announced, it may be of 

 interest to the readers of Science. 



Edw. J. Nolan. 

 Philadelphia, Jan. 17. 



Abbott's Greek reader. 



I like the freshness and independence of your 

 critical comments. But you object to the publishers 

 of Abbott's ' Greek reader ' binding the notes sepa- 

 rately from the text. ' Much ' may be ' lost in con- 

 venience,' as you say, but some of the best instruct- 

 ors in the classics object to notes in the classroom, 

 in the hands of the student. They are entirely too 

 convenient, a great hinderance to the best mental 

 discipline, and a temptation to neglect thorough 

 preparation beforehand. E. T. Jeitebs. 



Lincoln univ., Chester co., Penn., 

 Dec. 29. 



Adverjbising for professors. 



Science and education for Dec. 24, on p. 65, 

 speaks of advertising for professors. 



The University of Mississippi recently advertised. 

 There were five vacancies and five hundred and 

 twenty-seven applications ! M. W. Easton. 



