14 
and subfamily names the name of the type genus is taken as basis, 
and the endings idee and inse are added to the root of the generic 
name in question. Thus the tapeworms in man are classified as 
follows: 
Family Tseniidse, based upon Taen ia as its type genus. 
Subfamily Tseniinae, based upon Taenia as its type genus. 
Genera Taenia and Echinococcus. 
Subfamily Dipylidiinse, based upon Dipylidium as its type genus. 
Genera Dipylidium and Hymenolepis. 
Subfamily Davaineinse, based upon Davainea as its type genus. 
Family Dibothriocephalidse, based upon Dibothriocephalus as its type genus. 
Subfamily Dibothriocephalinae, based upon Dibothriocephalus as its type genus. 
Genera Dibothriocephalus , Diplogonoponis , and Sparganum. 
A moment's consideration will show that this method of forming 
family and subfamily names is based upon practical considerations; 
by having a uniform set of endings we know that any name ending in 
iclse is of family rank, while one ending in inse is of subfamily rank. 
Further, by using a prominent generic name as basis for the family 
and subfamily names we aid the memory in locating the systematic 
position of the groups. 
Art. 5. The name of a family or subfamily is to be changed when 
the name of its type genus is changed. 
Discussion. — While one of the fundamental purposes of the code 
is to prevent an unnecessary change of names, it is considered that 
under certain circumstances changes must be made for the general 
good. As illustrating such an event, and as explaining article 5, the 
following example may be taken: 
“ Distoma hejjaticum" is a parasite mentioned in most works on 
practice of medicine; it is frequently classified in the family “ Disto- 
midse of which it forms the “type.” The correct name of this 
parasite is Fasciola hepatica , and upon suppressing the generic name 
Distoma , in favor of Fasciola , the family name Distomidse is changed 
to Fasciolidse. Were this change not made, we should be obliged to 
carry in our minds a family name ( Distomidse ) and a subfamily name 
( Distominse ) without any direct clue as to their systematic position; 
further, in this and in many other instances confusion would arise 
between the family name of this group of parasitic worms, and a 
family name used for an entirely different set of animals. 
GENERIC AND SFBGEXEEIC NAMES. 
Art. 6. Generic and subgeneric names are subject to the same rules 
and recommendations, and from a nomenclatural standpoint the}’ are 
coordinate, that is, they are of the same value. 
Discussion. — The question as to whether a given systematic unit 
should be given generic or subgeneric rank, is to no little extent sub- 
