ON ZOOLOGICAL NOMENCLATURE. 
25 
super, the former being intermediate between the rank of the term to 
which it is prefixed, and the next lower, the latter between the same term 
and the next higher. 
The botanical terms are not precisely interchangeable with those nsecl in zoology, 
owing to the differences in the subjects classified and for other reasons; this is espec- 
ially the case with the terms order and family, in the two series. A special series of 
terms to indicate sports , hybrids, etc., is in use in botany which is exhaustively treated 
of by DeCandolle. 
§X. The definition of each of these terms or names of groups varies, 
up to a certain point according to the state of science or the views of the 
individual writer using them, but their relative rank, sanctioned by usage, 
cannot be inverted. No classification containing inversions, such as a di- 
vision of a genus into families or of a species into genera can be ad- 
mitted. (DC.) 
§ XI. In botany subdivisions of a species are usually indicated by fig- 
ures (1, 2, 3, etc.) and subdivisions of varieties by Greek letters ( a , p, a, etc.) 
but in zoology it is a common practice to denominate the subspecies by 
distinct names which are appended to the specific name, as Ovis ammon 
subsp. crassicornis. 
On the Manner of Designating Particular Groups or those 
belonging to the Second. Category of § VII. 
§ XII. Each natural group of animals or plants can have but one valid 
designation. (DC., B. A., Bourg., etc.) This designation by modern 
usage is allowed to exist simultaneously in zoology and botany without 
rendering either application of it invalid, but in either department it can 
be applied in a valid manner but once. 
§ VI should be kept in mind. “We refer solely to the Latin or systematic language 
of zoology (and botany). We have nothing to do with vernacular designations.” (B. 
A.,Th.) 
The special application of this principle to genera and species will be treated under 
their specific heads. 
§ XIII. This designation should only be changed for the most important 
reasons, founded on a thorough knowledge of the facts; or on the neces- 
sity of abandoning a denomination on account of its being in conflict 
with the following rules or with the essential principles of systematic 
nomenclature. This necessarily follows from § III. 
§XIV. The form, number and arrangement of the names are depend- 
ent on the nature of each group, according to the rules which follow. 
DENOMINATION OF THE HIGHER GROUPS. 
GROUPS OF HIGHER VALUE THAN FAMILIES OR BOTANICAL ORDERS. 
§ XV. The names of these groups are taken from some one of the prin- 
cipal characters. They are expressed by single words of Greek or Latin 
