THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS. 35 



They do not wink when the whole hand or a finger is moved close before their eyes, 

 but when the eye-lashes are touched or all but touched, they do wink. The same reflex 

 follows where the lid or corner is actually touched. 



It is very diificult to make out the pupil, and I was not able to learn, though I tried 

 day after day, whether the iris contracted to light or not. Xo evidence of the existence of 

 vision could be obtained. 



A feather inserted into the nostril causes the head to be quickly drawn away. 



Considerable twitching of the muscles is noticed when they are asleep. 



There is a tendency to growling in sleep. 



All the movements are better than on the earlier days ; and for the first time, slight 

 tail movements are noticed, none having been observed during the period prior to opening of 

 the eyes. 



When a puppy is removed from the others in its pen it manifests little uneasiness, but 

 quite the reverse if placed on the floor of the kennel which is covered with sawdust. It 

 creeps about and cries. 



14//( day. — Unable to get any evidence of seeing objects as no sign is given of any kind 

 when various things are moved before the eyes ; nor is the winking reflex any better 

 established. 



They seem as before to crawl against the board wall of the pen without noticing it. 

 The ej'es are more fully opened. 



The loudest noises, including the sounding of a shrill dog whistle, that can be easily 

 hoard a quarter of a mile away, causes no reflex movements of the ears, or any other move- 

 ment to indicate the possession of hearing. On the other hand a sliglit lireath of air causes 

 reflex movements. 



To-day I made a definite test of the temperature sense. A glass pestle was heated till it 

 could not be comfortably borne on my skin anywhere, when its end, aliout half an inch in 

 diameter, was placed against the paw of the puppy which was rapidly withdrawn. A 

 similar I'eaction followed the application of ice but not so quickly. 



They now begin to use the /V(*r.s apart from sucking. They stand better and move faster, 

 the hind limbs being, however, much less under control than the/V(»/(^ legs. 



I suspected that the beginning of play appeared to-day, but was not quite certain. 



The tendency to growl is manifesting itself in sleep. 



Ibtlt Jay. — Eyelids continue to grow ajjart so that more ot the globe of the eye can be 

 seen. They seem to wink reflexly a shade more readily under the former tests, but more 

 promptly with the finger close to tlie eye than with the entire lumd moved as close as pos- 

 sible before the face. 



One puppy appears to see or be trying to see the dam judging by the position of the head, 

 etc., but it is possible that it is partly guided by smell. I allowed the dam to stand just 

 within the pen at some little distance (one or two feet) from the puppies lying asleep or 

 drowsy. An uneasiness was manifested which increased, and was probably due to their 

 smelling the dam. 



On bringing some sulphuric ether towards the nostrils of one of the puppies there was 

 decided evidence of dislike. 



When they are lying asleep, touching the lips gently causes movements of the muscles 

 of the face, and especially of the tongue — an incipient sucking in fact. All tests of hearing 



