OF TRILOBITES. 5 



while ranging over the more recondite portions of the study, threw for the first time the 

 whole Trilobite group into a series of natural families. And these must be, I conceive, the 

 basis of any true classification of the order Trilobita. The separation of the large-eyed 

 Trilobites with eleven body-rings, was not indeed due to Emmerich, but to Quenstedt ; but 

 Dr. Emmerich's essay confirmed this important view, named the group Phacops — our first 

 described one, and went on to apply the principle thus gained to the arrangement of the 

 whole. The species are carefully made out, the synonyms collected, and a model set for 

 all succeeding works. 



Other observers were not idle. Von Buch, Bronn, Green, Goldfuss, and Miinster were 

 figuring the new species with various merit ; and Milne-Edwards had compiled all the 

 known synonyms in his great work on the Crustacea. In 1843, three most important 

 works appeared, in one of which Dr. Burmeister placed before the German reader all the 

 facts regarding the history, structure, and affinities of the group, while Dr. Goldfuss gave 

 a systematic arrangement of Trilobites and description of new species in the ' Jahrbuch ' 

 for 1843. In England, the profound and careful work of the late Gen. Portlock first 

 called attention to all the new discoveries which had been making abroad, while the many 

 new forms which he described and illustrated 1 have given his work the very highest rank. 

 The American species began now to be figured by Hall, and Emmons, and Vanuxem ; 

 Loven was producing his classic descriptions in the Transactions of the Swedish Academy. 

 (Ofvers. Kongl. Vetensk. Akad., 1844, &c.) ; Emmerich repeated and improved his classi- 

 fication in the ' Neues Jahrbuch' for 1845; Dr. Beyrich, in 1846, was giving us his 

 accurate descriptions of species ; and in the same year appeared the - Notice Preliminaire ' 

 of M. Barrande, the herald of a work which has thrown nearly all other works on trilobites 

 into the shade. 



This remarkable sketch by M. Barrande, the fruit of thirty years of labour, indicated 

 at once the commencement of a new era for the group. A supplement published by M. 

 Barrande the same year raised the number of described Bohemian species alone to 152. 

 The rich " terrain " which M. Barrande has so emphatically made his own still furnished 

 abundant work for Beyrich; and M. Corda, the keeper of the National Museum at Prague, 

 even attempted to snatch the " spolia opima" from the hand that had won them. The 

 ' Prodrom einer Monographie der Bohmischen Trilobiten,' while it attests the rapid industry 

 of the well-known botanist of Prague, shows how little is gained by hasty generalisation, 

 and especially " appropriation " in natural history. It was a melancholy failure. While 

 M. Barrande had patiently traced the metamorphosis of some thirty different kinds of 

 Trilobites, and was preparing for their illustration, these young and undeveloped Trilobites 

 were figured by Corda as so many distinct genera and species. A certain number of new 

 forms were doubtless named, and a few errors of nomenclature corrected ; but the absurd 



1 Ilia illustrations do not do him justice. Owing to a misfortune of the printers, the whole of the 

 beautiful plates drawn for the work by Mr. G. Y. Dunoyer had to be hastily transferred by an employe, 

 and the character is greatly lost in the transfer. 



