1896. ] RULES OF ZOOLOGICAL NOMENCLATURE, 317 
at the same date, so that the priority cannot be ascertained, the 
decision of the first author that points out the synonymy should 
be followed. 
17. In the case of species with a cycle of generation of different 
forms, the specific term must be taken from an adult form capable 
of reproduction. In these cases, as also in species in which 
Polymorphy occurs, the Law of Priority must be observed. 
18. The author of the specific name is the author of the species. 
19. The author’s name should be placed in parentheses when 
the original generic name is replaced by another. 
20. Hybrids should be designated either by a horizontal cross 
between the parents’ names, or by these names being placed one 
above the other with a line between. The parents’ sexes should be 
stated, when known. ‘The name of the describer of the hybrid 
should be added, preceded by a comma. 
C, RULES FOR THE NAMES OF SUBSPECIHS AND OTHDR DIVERGENCES 
FROM TYPICAL SPECIBS OR SUBSPECIES. 
21. When constant local forms, varieties, strains, &c. require 
special names, these names should be placed after the specific name. 
The rules for such names are the same as those for specific names. 
D. RULES FOR GENERIC NAMES, 
22. Names of genera should be substantives, and of the singular 
number. They should be one word and be written with a large 
initial letter. Ifa subgenus is used, its name (which follows the 
same rules as a generic name) should be given in parentheses after 
the generic name. 
23. A generic name is only valid when a known or a sufficiently 
characterized species (or several species) is referred to it, or when 
a sufficient diagnosis of it is given. 
24. The same generic name can only be employed once in Zoology 
Nor can names already proposed as subgeneric be employed also 
as generic names in another sense. 
25, Whenseveral generic names are proposed for a genus at nearly 
the same date, so that their priority cannot be settled, the name for 
which a type-species is given is to be preferred. In all uncertain 
cases the decision of the author who first arranges the synonymy 
is to be followed. 
26. When a genus is separated into several genera the old name 
must be retained for the type-species. If this cannot be positively 
ascertained, the author who splits up the genus must select one of 
the species originally in the genus as the type. When a subgenus 
is raised to generic rank the subgeneric name becomes the generic 
name. 
E. RULES FOR THE NAMES OF THE HIGHER SYSTEMATIC GROUPS. 
27. Names for higher systematic groups of animals must have a 
plural termination. 
