Literary Notices. xlvii 



Recently objection has been made to the use of the terms pero 

 and pes as applying to the peripheral and central parts of the olfactory 

 bulb. The grounds upon which we first adopted the terms were very 

 explicitly indicated, i. e., the belief that the ectal part of the organ 

 is very distinct in structure and origin from the ental structures. 

 This conviction which was at first a feebly supported hypothesis has 

 received the most important confirmation from the standpoint of his- 

 togenesis and phylogeny. There seems at present no reason to doubt 

 that the pero is largely derived from without. The fibres from the olfac- 

 tory epithelium grow toward the part or parts of the cerebrum which are 

 to become their temporary hosts, and adhere, for a time slightly, and af- 

 terwards enter into a more or less complete association with the 

 modified cortex at that point. The resulting structure is the pero, 

 while the ventricular and unmodified parts constitute the pes. If it 

 were otherwise we should expect that the tuber would always arise 

 from a constant locus of the cerebrum, which is far from being the 

 case. In serpents the point where the olfactory fibres impinge on the 

 cerebrum is far laterad and the tuber of serpents is not fully homolo- 

 gous with that of birds, for example. 



The changes proposed by Dr. Ayers relate to the auditory nerve. 

 "The terms, N. vestibuli and N. cochleae, are ill-chosen, from the 

 fact that the morphology of the ' vestibule ' and its parts as con- 

 ceived by the anatomists who first proposed this term has no real ex- 

 istence. On the other hand, the term N. cochlearis is unsuitable, not 

 to say inadequate, from the fact that this nerve is not solely a coch- 

 lear nerve since it trunk contains nerves to the ' vestibule ' as well, 

 viz., the sacular and posterior ampullar nerves wherever these are not 

 provided with separate foramina. The central relation of these two 

 nerves is always with the mass of cochlear fibres in those forms pos- 

 sessing an enlarged cochlear apparatus, as well as in the more primi- 

 tive condition of the auditory organ. 



"While engaged in reconstructing our anatomical nomenclature 

 it is very "desirable that we choose those terms which express the pres- 

 ent condition of our knowledge and give promise of being adequate 

 for the future as well, for, I take it, the recent movement for a bet- 

 terment of biological nomenclature is dominated by the universal de- 

 sire for as simple, short, and expressive a terminology;as shall be ade- 

 quate not only to the science as it exists today, but also to its expand- 

 ed condition in the not distant future. None of these conditions are 

 fulfilled by any of the terms yet applied to the ear-nerve except the 

 two, utricularis and sacculans. " 



