402 0. C. Marsh — Value of Type Specimens 



Among the vertebrates of the past, the case is much more 

 Berions, and here especially reform in methods is a pressing 

 necessity. From the nature of the case, the older extinct 

 forms are usually represented by fragmentary remains, the 

 investigation of which is one of the most difficult problems 

 offered to natural science. A single tooth or a vertebra 

 may be the first specimen brought to light in a new region, 

 and thus become the sole representative of a supposed new 

 form. The next explorer may find more perfect fragments of 

 the same or similar forms, and add new names to the category. 

 A third investigator, with better opportunities and more 

 knowledge, may perhaps secure entire skulls or even skeletons 

 from the same horizon, and thus lay a sure foundation for a 

 knowledge of the fauna. 



As the number of described forms increases, the necessity 

 of a direct comparison of types becomes imperative, and the 

 comparative value of each type specimen is thus brought into 

 notice. It will then frequently be found that not a few are 

 uncharacteristic, while others are too incomplete to disclose 

 their own essential features, and hence of little aid in indica- 

 ting the affinities of forms found with them. 



Type specimens that do not show characteristic features are, 

 of course, of little value to science, and many such prove a 

 delusion and a snare to the investigator, however faithfully he 

 may endeavor to study them. The imperfect types require 

 still more labor to decipher them. Not a few specimens to-day 

 are types, for the simple reason that they are imperfect. If 

 they had been entire when described, their true nature would 

 have been recognized, and much confusion in nomenclature 

 have been avoided. The chance preservation of some marked 

 features may, indeed, give a hint as to what the whole specimen 

 once was, but too often a suggestion only is thus offered, while 

 the real nature of such types must always remain in doubt. 



A type in Paleontology should consist of the remains of a 

 single individual, and this should stand as the original repre- 

 sentative of the name given. A second specimen, or even 

 more, may be used later to supplement the first, but not to 

 supplant it. This, however, has been done by some authors, 

 with the natural result of causing endless confusion in the 

 nomenclature. 



The Selection of Type Specimens. 



The descriptions in Paleontology are too often descriptive 

 only, and not comparative. This, if well done, is preferable 

 to long academic discussions in regard to the affinities of a 



