0. C. Marsh — Value of Type Specimens, etc. 401 



Art. XL. — The Value of Type Specimens and Importance 

 of their Preservation ; * by O. C. Marsh. 



In the present state of Natural Science, there are too many 

 obstacles in the path of the original investigator. That this is 

 the case in the study of Botany, we may well believe, as 

 authorities of that Science have frequently placed the fact on 

 record. It is certainly true that everyone who does original 

 work in systematic Zoology, either among the living or extinct 

 forms, meets many difficulties at the start in endeavoring to 

 ascertain what others have done before him. The literature 

 of the subject is often discouraging from its extent, and 

 especially from its uncertainty. If the work in hand requires 

 the comparison of type specimens, the difficulties greatly 

 increase, and often prevent definite conclusions. The type 

 will frequently be found the most important element in the 

 problem, far more so than the literature, however extensive. 

 This is more especially true among the extinct vertebrates, with 

 which the present communication mainly deals. 



(1) The Value of Type Specimens. 



The value of a type depends first of all upon whether it is 

 a characteristic specimen, worthy of being the representative 

 of a new group of individuals. Without this distinctive 

 quality, its importance is greatly diminished. If, for example, 

 the specimen first described is immature, its essential features 

 may thus be obscured, and its value as a type much diminished. 

 On the other hand, a very old animal may be uncharacteristic. 

 The teeth of a mammal, for instance, may be worn down or 

 even lost, so as to make the normal dentition uncertain. This 

 is true of recent forms, but is more important if the type 

 belongs to an extinct fauna, as then the chance of duplicating 

 it is much less. 



The value of a type specimen again may depend largely 

 upon its completeness. Among the invertebrates, especially 

 those now living, types are usually complete enough to show 

 the more important features. This, however, is far from being 

 the case among extinct forms, particularly from the older 

 formations, and the records of Paleontology are burdened with 

 the names of many fragmentary fossils, types of species 

 practically unknown. 



* Read before Section B, International Congress of Zoology, Cambridge, 

 England, August 23, 1898. 



