ORIGIN AND DEVELOPMENT OF INSTINCTS. 189 



ancient times in the East, when flying pigeons was much 

 esteemed. Tumblers have the habit of flying in a close 

 flock to a great height, and as they rise tumbling head over 

 tail. I have bred and flown young birds, which could not 

 possibly have ever seen a tumbler; after a few attempts 

 even they tumbled in the air. Imitation, however, aids the 

 instinct, for all fanciers are agreed that it is highly desirable 

 to fly young birds with first-rate old ones. Still more 

 remarkable are the habits of the Indian sub-breed of tumblers, 

 on which I have given details in a former chapter, showing 

 that during at least the last 250 years these birds have been 

 known to tumble on the ground, after being slightly shaken, 

 and to continue tumbling until taken up and blown upon. 

 As this breed has gone on so long, the habit can hardly be 

 called a disease. I need scarcely remark that it would be as 

 impossible to teach one kind of pigeon to tumble as to teach 

 another kind to inflate its crop to the enormous size which 

 the pouter pigeon habitually does."* 



This case of the tumblers and pouters is singularly 

 interesting and very apposite to the proposition before us, for 

 not only are the actions utterly useless to the animals them- 

 selves, but they have now become so ingrained into their 

 psychology as to have become severally distinctive of different 

 breeds, and so not distinguishable from true instincts. This 

 extension of an hereditary and useless habit into a distinction 

 of race or type is most important in the present connection. 

 If these cases Btood alone they would be enough to show that 

 habits may become hereditary, and this to an extent 

 which renders them indistinguishable from true instincts.t 



In the Appendix several instructive cases of the same 

 kind will he found, such as that of the Abyssinian pigeon, 

 which, when fired at, " plunges down so as almost to touch 

 tin- sport -man, and then mounts to an immoderate height;"J 

 the biscacha, which "almost invariably collects all suits of 



• For farther particulars on t ho instinct of tumbling, sco Variation qf 

 Aii/muis mill Plant*, vol. i, p. 219, and 280. 



I Si. mi- Tears, ago tin' Etatels which with oonfined in one i':i_v ol the 

 Zoological Gardens acquired the apparently uaeleai hal.it of perpetually 

 tumbling hea I prer heeu. II' their progeny jrere t<> be exposed tor a number 

 nt' generations to similar conditions of life, they would probablj develops i 

 trio- instinct "f turning somersaults analogous to thai of the tumbler- 



X I have fieipicnth D I i .' I a similar [<v iponsitj in the Lapwing. 

 9 



