434 ANIMAL INTELLIGENCE. 



With, reference to this case I wrote to 'Nature* as 

 follows. The friend to whom I allude was the late Dr. 

 Brydon, C.B. (the ' last man ' of the Afghan expedition 

 of 1841), whom I knew intimately for several years, and 

 always found his observations on animals to be trust- 

 worthy : 



In response to the appeal which closes Mr. Buck's interest- 

 ing letter (' Nature,' vol. viii., p. 302), the following instance of 

 ' collective instinct ' exhibited by an animal closely allied to the 

 wolf, viz., the Indian jackal, deserves to be recorded. It was 

 communicated to me by a gentleman (since deceased) on whose 

 veracity I can depend. This gentleman was waiting in a tree 

 to shoot tigers as they came to drink at a large lake (I forget 

 the district), skirted by a dense jungle, when about midnight 

 a large axis deer emerged from the latter and went to the 

 water's edge. Then it stopped and sniffed the air in the direc- 

 tion of the jungle, as if suspecting the presence of an enemy ; 

 apparently satisfied, however, it began to drink, and continued 

 to do so for a most inordinate length of time. When literally 

 swollen with water it turned to go into the jungle, but was 

 met on its extreme margin by a jackal, which, with a shai-p 

 yelp, turned it again into the open. The deer seemed much 

 startled, and ran along the shore for some distance, when it 

 again attempted to enter the jungle, but was again met and 

 driven back in the same manner. The night being calm, my 

 friend could hear this process being repeated time after time 

 the yelps becoming successively fainter and fainter in the dis- 

 tance, until they became wholly inaudible. The stratagem thus 

 employed was sufficiently evident. The lake having a long 

 narrow shore intervening between it and the jungle, the jackals 

 formed themselves in line along it while concealed within the 

 extreme edge of the cover, and waited until the deer was water- 

 logged. Their prey, being thus rendered heavy and short- 

 winded, would fall an easy victim if induced to run sufficiently 

 far, i.e., if prevented from entering the jungle. It was, of 

 course, impossible to estimate the number of jackals engaged in 

 this hunt, for it is not impossible that as soon as one had done 

 duty at one place, it outran the deer to await it in another. 



A native servant who accompanied my friend told him that 



. this was a stratagem habitually employed by the jackals in that 



place, and that they hunted in sufficient numbers ' to leave 



nothing but the bones.' As it is a stratagem which could only 



be effectual under the peculiar local conditions described, it 



