Literary Notices. “xXvil 
396). The morphological objections are still more serious. In the 
first place, the structure of the olfactory epithelium is totally unlike 
that of the organs of the auditory and lateral line systems, where hair 
cells extending only part way through the epithelium are always pres- 
ent. The methods of stimulation of the two sets of organs are totally 
different and it is not easy to see how one could have been derived 
from the other. And finally, all of the acustico-lateralis nerves ter- 
minate in the brain in a single center with very characteristic con- 
nections, which are totally unlike those of the far distant olfactory 
center. 
At the close of the discussion of the cranial netves we find this 
excellent passage: ‘‘ From what has been said above it is clear that 
the usual arrangement of the cranial nerves in twelve pairs does not 
represent their true relationships with one another. ‘The various pairs 
are serially homologous neither with one another nor with the typical 
spinal nerves, nor can they be regarded as representing twelve cranial 
segments. Indeed, it would seem that comparatively little information 
with regard to the number of myotomic segments which have fused to- 
gether to form the head is to be derived from the cranial nerves.” 
On page 458 we read, *‘ Nothing is yet known concerning the 
development of the various forms of tactile organs,” the author having 
apparently overlooked the papers by SzyMoNnowicz in the Archiv f. 
mikr. Anatomie, 1895 and 1896. 
The adverse criticisms above are, however, relatively insignificant 
as compared with the general excellence of the discussion as a whole, 
which is clear and philosophical in design and treatment. 
QO 
sd 
x 
Motor Nerve Termini in Insects. ! 
The motor nerve terminations in the striated muscles of insects 
have been studied by various methods by many histologists, among 
whom may be mentioned RouGET, RANVIER, FOETTINGER, V. THAN- 
HOFFER, CIAcciO, BIEDERMANN, RAMON y CajaLt and R. MonrTt. 
These investigators have disagreed in many points, but the author di- 
vides them into two main classes. The first class includes those, who, 
like RANVIER, recognize in the striated muscles of insects, as in those 
of the higher animals, a Dovkre’s elevation consisting of granular pro- 
toplasmic substance containing more or less numerous nuclei. The 
nerve fiber, when it reaches this elevation, loses its sheaths, the neuri- 
1 Sulla terminazione nervosa motrice nei muscoli striati degli insetti. Pre- 
liminary note by ALBERTO AGGAZZOTTI. 
