EXAMINATION OF SOME SPINAL NERVES 155 
Monkey : — Transection above 1st cervical — 
right IXth post-thoracic root . . flexion of great toe. 
„ Vlllth „ „ . . „ great toe. 
„ Vllth „ „ . . „ great toe, knee, and hip. 
Vlth „ „ . . „ great toe, knee, and hip. 
„ Vth „ „ . . „ great toe, knee, and hip. 
. IVth „ „ . . „ hip and knee. 
Ilird „ „ . . „ hip. 
Turning of the head and neck away from the side excited is obtained as a bulbo-spinal 
reflex from stimuli to nostril, lip, back of cheek, pinna, back of neck, or from nerve-roots, e.g., 
Vth cranial, Ist, Ilnd, Ilird, often from IVth and Vth, cervical nerves ; this movement is similar 
to that discovered as a cortical reaction by Ferrier, and studied by Schafer, Munk, and others. 
I would call it the wry-neck reflex. It is another example of an action usually considered to be 
peculiarly 'cortical' in character, but really pre-eminently represented also in the 'lowest level' 
centres, as Hughlings Jackson terms the bulbo-spinal. 
A very striking character of the reflexes elicitable from the isolated Mammalian cord is the 
machine-like want of variation with which, on repeating the stimulation, the movement is repeated. 
Of this fatality, temporal monotony, or monotonous repetition, it is not necessary to give further 
example than the flexion of thumb or hallux that follows uniformly each time the little finger or 
toe is pinched. It is true that after the first few repetitions [Bahnung) a slighter pinch than that 
required at first generally becomes adequate, or the reply from the same degree of stimulus becomes 
more extensive, and that after twenty or thirty repetitions an interval may ensue during which the 
movement becomes less, and may even be scarcely perceptible ; then it returns again gradually, 
recovering, as it were, from fatigue. The breakdown due to fatigue appears to involve the afferent 
rather than the efferent apparatus^ at least to affect it earlier^ for, if another finger or toe be excited, 
the movement is at once elicited from it, in accordance with the rule of spatial monotony. 
Among the deep reflexes a good example of monotony of repetition is contraction of the median 
part of the gracilis muscle, which occurs each time one of the two tendons of the tibialis anticus 
muscle is nipped above the annular ligament (Cat). 
The 'March' in Spinal Reflexes of Short Path 
The reflex movements elicitable from the Mammalian spinal cord after cross-section are 
often extremely brief— surprisingly so; in fact, as Fick* has pointed out in dealing with the 
dorsal nerves of the Frog, often like simple motor twitches. The movements have seemed to me 
most brief when least vigorous and most limited in extent, more so in the Monkey in its early 
condition subsequent to cord-section than in the Cat and Dog under similar conditions. Stimuli 
that at first elicit only a single movement of a single joint, later elicit frequently a short sequence 
of movements about a series of joints ; the capacity for developing a sequence is much earlier 
regained by the isolated cord of Cat or Dog than by that of Monkey. 
* Pfliiger's ' Archiv,' vol. 3. See also Erlenmeyer and Wundt. 
