THE INTERNATIONAL CODE OF ZOOLOGICAL NOMEN- 
CLATURE AS APPLIED TO MEDICINE. 
By Ch. Wakdell Stiles, Ph. D., 
Chief of Division of Zoology , Hygienic Laboratory , U. S. Public Health and Marine- 
Hospital Service. 
INTRODU CTTOIN. 
Repeated requests have been made by pathologists, bacteriologists, 
and zoologists of this country that a bulletin be issued giving the 
present International Rules of Zoological Nomenclature, explaining 
their use and practical application, and showing their influence upon 
the nomenclature used in medicine. In response to these requests 
the present paper has been prepared. 
In treating the subject, the code is given seriatim, as at present in 
force; under each rule or recommendation explanations and examples 
are given when necessary. In these explanations, however, I do not 
discuss the subject in my capacity as secretary of the International 
Commission, but rather in my professional capacit} T as a zoologist. 
Purpose of the code. — Zoologists are obliged to deal with hun- 
dreds of thousands of technical names. In a summary of the animal 
kingdom Ludwig (1886) estimated that there were then 312,015 known 
species of animals, divided as follows: Vertebrates, 27,100; tunicates, 
300; mollusks, 42,215; molluscoidea, 5,160; arthropods, 212,975; worms, 
5,700; echinoderms, 6,210; coelenterates, 6,225; protozoa, 6,130. This 
estimate must be considered as conservative even for the year 1886. 
Ashmead (1895) estimated the number of known Species of insects 
at 281,000, a total which exceeds the estimate made by Ludwig (1886) 
for all the arthropods (insects, mites, crustaceans, etc.). Howard 
(1905) has been kind enough to estimate for me the total number of 
known and unknown species of insects for the world, which he thinks 
is between 3,500,000 and 1,000,000. 
Scudder (1882) collated about 79,000 generic and supergeneric 
zoological names, and Waterhouse (1902) collected 29,683 additional 
names. Waterhouse estimates that from 1880 to 1900 about 1,150 new 
generic and supergeneric zoological names were proposed annually. 
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