99 
ideas, of the several groups to which they are applied, and thus enable 
the reader to at once compare separate systems, and discover their differ- 
ences; thirdly, the facility with which they enable a writer to state the 
difference between different systems of classification. To give an in- 
stance :— 
According to some systematists, the sub-kingdom (Archetype) Ver- 
tebrata is divided into the classes (Primary Types), Mammalia, Aves, 
Reptilia, Batrachia, Pisces. According to others, this sub-kingdom 
(Archetype) is divided as follows :—Classes (Primary Types), Mammalia, 
Birds, Hemacrymes. Of these, the class Hemacrymes is again divided 
into the sub-classes— Reptilia, Pisces; the Reptilia being again di- 
vided into the orders (Secondary Types) Batrachia, Ophidia, &c. Now 
it is manifest that if, instead of stating that Batrachia was, according to 
some, a class of Vertebrata, and, according to others, only an order of the 
Reptilia, which was a sub-class of Heemacrymes, a Vertebrate class, that 
we made the statement,—Batrachia, according to some, a Vertebrate pri- 
mary type ; according to others, a secondary Vertebrate type,—the exact 
relations between the values assigned by the two systematists would be 
at once understood ; and this, I conceive, would be one great advantage 
of the proposed nomenclature, that, no matter how our ideas about the 
value of the groups themselves might vary, that of the value of the 
names would necessarily remain the same; all that would occur in case 
of a change in our ideas of the value of groups, being the transference of 
the group to a higher or lower division, as the case might be. It must 
not be thought that I claim any originality for this idea: the principle 
of it has been long recognised, as already stated, and the general idea 
of the necessity for a definite value to our divisional names will be found 
floating through all the later books of classification, a thing which, 
however, it appears, will be impossible as long as we use terms which 
by long-continued custom have come to be mere arbitrary names, with- 
out any definite connexion or mutual dependence on each other; and 
therefore, it would appear to be desirable to suppress them altogether, 
and substitute in their place others, the relationship between which is 
manifest, understood, and universally acknowledged. 
Dr. E. Perceval Wright said that, without entering into the details 
of the paper just read by Dr. Kinahan, he still thought that one of the 
most important objects which a universal nomenclature had in view 
would be altogether nullified if any of the terms used would suggest 
ideas foreign to the nomenclature; that hence he would suggest that the 
word ‘ archetype’ having been used by Professor Owen to represent an 
idea now familiar to all zoologists, it would not be advisable to have it 
appearing at the head of a new nomenclature with a very different idea 
attached to it. He would not occupy the Academy by entering into the 
merits or demerits of Dr. Kinahan’s paper. If a satisfactory universal 
nomenclature was ever invented, it would be a very great boon, indeed, to 
the systematist, nor would it be without great benefit to the comparative 
anatomist also. 
R. I. ACAD. PROC.-——YOL. VIT. Q 
