SCIENTIFIC SURVEY. 21 



edge of the whole would be needed. This is impossible for one 

 man to attain. 



Linneus, therefore, while he conformed as far a& he was able to 

 what he considered natural orders, thought it advisable to adopt 

 what has been called an artificial system, establishing classes, 

 orders, genera and species upon certain organs which are always 

 present and uniform in form, position and structure. By these 

 means the study and description of natural objects have been 

 admirably systematized and facilitated. These important aids have 

 wonderfully promoted investigation and research, and increased 

 the knowledge of natural history in all its branches. 



Different individuals, following their taste and "bent of their 

 genius" have devoted themselves to diiferent departments of the 

 science. Some making Botany, some Ornithology, some Entomol- 

 ogy, some Ichthyology, others Mineralogy and Geology, and so 

 on, their speciality, thus becoming adepts in their favorite science. 

 New discoveries have brought new changes in grouping or classi- 

 fication, and it will be found in tracing back the progress that has 

 thus far been made, that the arrangement of the present day is very 

 different, in many important respects, from the systems adopted 

 and promulgated by our predecessors — each of which had its day. 

 In Ichthyology this has been especially the case, and as many of 

 the terms, and some of the orders and genera are still used by 

 modern writers on this science, it may be useful to look briefly over 

 some of the several classifications which the older Ichthyologists 

 adopted in their works. We shall thus more understandingly pur- 

 sue the science as arranged by the more modern writers. As long 

 ago as 1555, Belon, a French physician, wrote a work entitled 

 " The nature and diversity of fishes with their portraits J^ He was 

 the first who divided or grouped fishes into two grand divisions of 

 cartilaginous and osseous fishes. 



Willoughby and Ray were among the earliest authors who re- 

 duced the study of Ichthyology to something like a systematic 

 arrangement. Their work made its appearance in 1686, in four 

 Books, folio. 



