This is called the /binomial/ (two-name) /nomenclature/. It was introduced by Linnæus, and greatly simplified the system of naming. The rule in scientific nomenclature is that all names must be Latin or Latinized. This gives a universal language by which scientists of all countries understand one another.
The names of classes (the highest groups) and subclasses are adjectives or adjective nouns, expressing the most prominent characteristic of the class or subclass. Thus the four subclasses of the class /Algæ/ are:
/Cyanophyceæ/ (subclass of blue-green algæ).
/Chlorophyceæ/ (subclass of grass-green algæ).
/Phæophyceæ/ (subclass of dusky-brown or olive-green algæ).
/Rhodophyceæ/ or /Florideæ/ (subclass of red algæ).
Orders are, with few exceptions, the names of genera with the termination /-aceæ/, as:
/Ectocarpaceæ/, from the genus /Ectocarpus/.
/Gigartinaceæ/, from the genus /Gigartina/. [pg029]
Suborders, or groups between orders and genera, terminate in /-eæ/. Names of genera are nouns or words taken as nouns. They are derived from any source,--from prominent or peculiar characteristics, from localities, or from names of botanists,--or they may be wholly arbitrary. Personal generic names are divested of titles and take a final /a/, or, in many cases, for euphony, /ia/. Thus, /Ulva/ is the Latin for "sedge"; /Ectocarpus/ is from two Greek words meaning "fruit outside"; /Corallina/ means "coral-like"; /Grinnellia/ is named for Mr. Henry Grinnell.
The specific names are commonly adjectives, but sometimes they are nouns, and occasionally are the names of the botanists who first described the plants, in which case the name terminates in /-i/ or /-ii/. The specific name always follows the generic name, thus:
/Ectocarpus Hooperi/, a species of /Ectocarpus/, first described by Mr. Hooper.
/Grinnellia Americana/, a species, peculiar to America, of a genus named for Mr. Grinnell.
/Griffithsia corallina/, a species resembling coral, and belonging to a genus named for Mrs. Griffiths.
With regard to the four subclasses mentioned above, it should be said that algæ are strictly classified in accordance with their methods of reproduction; but since allied species have, with few exceptions, the same color, the classification by colors is generally adopted as convenient and sufficiently precise.