1896.] EULBS OP ZOOLOSIOAL NOMBN'CLA.TU'RB. 317 



at; the same date, so that the priority cannot be ascertained, the 

 decision of the first author that points out the synonymy siiould 

 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 anotiier. 



20. llybrids 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. KULES FOB THE NAMES OF SUnSPBCIBS AND OTUEB DIVEEGENOES 

 FROM TXPIOAIi SPB0IB3 OR SUBSPECIES. 



21. When constant local forms, varieties, strains, &c. require 

 special names, these names should be placed after the speciQc 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. If a subgenus is used, its name (which follows the 

 same rules as a generic name) should be given in parentheses aEter 

 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 FOB THE NAMES OF THE HISHBB SISTEMATIO GROUPS. 



27. Names for higher systematic groups of animals must have a 

 plural termination. 



