HISTORY OF ENTOMOLOGY. 449 
supposed essential distinction- of the genus, given at the 
head of the Class; and another, generally longer, and in- 
cluding non-essentials, given at the head of the Genus. 
The first he denominated the essential, and the latter the 
factitious or artificial character. He did not do for insects 
what he did for Botany, — draw up what he has called 
the natural character of a genus, which included both the 
others, and noticed every other generic distinction a . 
The older Naturalists used to treasure in their memo- 
ries a short description of each species, by which when 
they wished to speak or write of it they made it known. 
Thus, in speaking of the common lady-bird they would 
call it " the Coccinella with red coleoptra b having seven 
black dots." This enunciation of any object was at 
first called its Title ( Titulus), and afterwards its Speci- 
fic Name (Nomen specificum\ and by Linne was restricted 
to twelve words c . But as the number of species increased 
to remember each definition was no easy task ; that he 
might remedy this inconvenience, he invented what is 
called the Trivial Name [Nomen triviale), which ex- 
pressed any species by a single term added to its generic 
appellation, as Coccinella septem-punctata ,• and thereby 
conferred a lasting benefit, on Natural History. This con- 
venient invention has rendered it less necessary to restrict 
the Nomen specificum to twelve words : it is desirable, 
however, that the definition of a species should be as 
short as possible, and contain only its distinctive charac- 
ters. In his definitions and desci'iptions Linne was often 
very happy ; but sometimes, in studying to avoid pro- 
lixity, he forgets Horace's hint, 
a Linn. Philos. Botan. n. 87, 188, 189. 
b See above, p. 342, n. 5. c Linn. n. 291. 
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