652 ZOOLOGY SECT. 



it is impossible to overestimate. He gave each species a brief 

 diagnosis in Latin, so that any naturalist versed in his system could 

 recognise whether an animal or plant which came under his notice 

 was already described or not. In this way he, as it were, pigeon- 

 holed the facts of Biology, and so made the determination of the 

 proper place of any new fact a comparatively simple matter. By 

 universal consent, the Syslema Naturce is taken as a starting-point 

 by systematists. It is customary to place after the name of a 

 species the initial or abbreviated name of the writer by whom the 

 species was first distinguished and named. For instance, the 

 Bass, a common British Teleost, was named Perca Idbrax by Linnaeus. 

 In 1828, Cuvier and Valenciennes, in their great work on Fishes, 

 recognised that it was generically distinct from the Perch, and, 

 retaining the generic name Perca for the latter, called the Bass 

 Labrax lupus. In 1860, further investigations into the Perch family 

 necessitated placing it in the genus Morone, and, according to the 

 law of priority, the specific name lupus gives place to Idbrax, the 

 latter having been applied by Linnaeus. The Bass is therefore 

 correctly called Morone labrax, Linn., the more usual name, 

 Labrax lupus, Cuv. and Val., becoming a synonym. In deciding 

 all such questions of priority, the tenth edition (1758) of the Sy sterna 

 Naturce is taken as a starting-point : all species distinguished by 

 Linnaeus, and not subsequently split up into two or more species, 

 are distinguished by the abbreviation L. or Linn. For instance, 

 Canisfamiliaris, Linn, is the Domestic Dog, Passer domesticus, Linn. 

 the House Sparrow ; and names given by the older naturalists are 

 neglected unless endorsed by Linnaeus. 



In many respects the system of Linnaeus was eminently artificial ; 

 he relied too much on single characters in classification, and did 

 not take the totality of structure into sufficient consideration. He 

 divided the animal kingdom into the following six classes : 



1. Mammalia. 



2. Aves. 



3. Amphibia [including Reptilia and Amphibia]. 



4. Pisces. 



5. Insecta [including all the Arthropoda]. 



6. Vermes [including Molluscs, Worms, Echinoderms, Ccelen- 



terates, and Protozoa]. 



It will be seen that all the classes are of natural groups, with 

 the exception of the last, but that they are far from being of even 

 approximately equal value. The first four are what we still call 

 classes, but there is no attempt to unite them into a single group 

 of higher order ; and in this respect the classification of Linnaeus 

 falls behind that of Kay, who recognised the phylum Vertebrata 

 under the name of animals with blood. The fifth class, on the other 

 hand that of Insecta is the equivalent of an entire phylum, 



