BIOPSYCHOLOGICAL 619 



varies considerably in different breeds, and may even be modified 



in the course of the individual lifetime. 



The ordinary sequence is the following: 



(i) Isolation. — When the sheep is near the time of parturition, it 

 separates itself from the flock ; and it is well that it should be allowed 

 to do so. There is a search for a suitable place for the birth, and in 

 many cases, under modern farming conditions, this is unimportant, 

 for all the available places are much the same. 



(2) Scraping. — Having found a suitable place, conveniently a 

 slight depression, the sheep scrapes with her fore-feet alternately. 

 There can be little doubt that this is an outcrop of a practice estab- 

 lished under wild conditions. In most cases it is quite futile to-day. 



(3) Parturition. — The next chapter is the actual giving birth; 

 and it is of interest to contrast the behaviour of the gimmer (giving 

 birth for the first time) with that of the ewe of two or three years' 

 experience. The gimmer is in many cases puzzled by the appearance 

 of the lamb, sometimes actually afraid of her offspring. Even in the 

 domain of instinct, experience may count. The experienced ewe is a 

 better mother than the gimmer. 



(4) Licking clean, — The next step is licking the newborn lamb, 

 and it seems to be the taste of the amniotic fluid that Uberates the 

 maternal instincts. If the mother has once Hcked her lamb, she will 

 not let it go; but if she does not lick and cannot be induced to do so, 

 she is likely to forsake her newborn offspring. After the cleaning 

 begins the suckHng, and soon there is the return to the flock. 



Now if something occurs to perturb the normal sequence of 

 chain-instincts, things go wrong; and a good instance is "lamb- 

 theft". This is a famihar occurrence when the sheep that has not 

 yet given birth, but is approaching her time, licks the newly born 

 lamb of a neighbour ewe — her isolation not having occurred. The 

 result is that she adopts or steals the lamb which she has licked; 

 and this "misplaced affection" may be fatal to her own offspring. 

 Mr. Eraser interprets lamb-theft, convincingly we think, as the 

 result of the artificial conditions of the farm, which may allow the 

 sheep thus to get a taste of amniotic fluid prematurely. This liberat- 

 ing stimulus should normally follow parturition; if by chance it 

 precede it, then the mothering instincts are awakened before the 

 proper time, and the result may be lamb-theft or worse. 



This conception of instinct-chains or concatenations also illumi- 

 nates other cases we have discussed, such as Eabre's case (p. 622) 

 of the emergent mason-bee grub, which, after biting its way 

 through its own firm larval case, remains finally imprisoned by an 

 artificially added film of paper. 



Apprenticeship of the Worker-Bee. — As a corrective of the 

 impression of tyrannous automatisation that we get from some 



