^"S> 1 Chapman, What are Type Specimens ? 6l 



IQI2 J ' . / / 



A complete list ol types to he found in each museum should 

 be published by it, and kept uj) to date by periodical addenda. 



Dkfinitions of Types. 



The following is a selection of the most important and 

 generally useful terms which the writer has introduced into 

 the system used in the palaeontological collections at the 

 National Museum. Melbourne. The term " tectotyi)e " is 

 new : — 



Primary Types (Proterotypes).* 



Holotype (Schuchert, 1897). — " A holotype in natural history 

 is a particular individual deliberately selected by the author 

 of a species, or it may be the only example of a species known 

 at the time of original publication. A holotype, therefore, is 

 always a single individual, but may embrace one or more 

 parts, as the skin, skeleton, or other portions, such as the 

 obverse and reverse of a natural mould. When a holotype is 

 selected, but other specimens are als) described, the latter must 

 l)e known as paratypes. When no holotype is selected, and 

 more than one specimen is described, all become cotypes. 

 Therefore, the original material of any species cannot include 

 a holotype and cotypes, but may include a holotype and jiara- 

 type. or all may be cotypes." 



" Where the sexes are different and can be distinguished, 

 a male or female specimen should be selected as the holotype, 

 but not both." 



" A species described as new, and proving to be a synonym, 

 does not affect the type material of the species with which it 

 is synonymous. All such synonymous material, however, 

 should be carefully preserved and marked as holotype or cotype 

 under the original name, as well as under the one of which it 

 is known to be a synonym." 



" Where a holoty])e is founded on jiartial sjiecimens, exactness 

 can be secured by writing holoty})e (obverse), holotyj)e (dorsal 

 vertebra), holotype (right valve), &c." 



Cotype (Waterhouse, redefined by Oldfield Thomas). — " A 

 cotype is one of two or more specimens, together forming the 

 basis of a species, no type [holotype] having been selected. 

 No species would have both type [holotype] and cotypes. but 

 either the former [or holotype and paraty]>e] or two or more 

 of the latter." 



Paralype (Thomas). — " A paratype is a sjiecimen belonging 

 to the original series, but not the type [liololvj^c], in cases 

 where the author himself selected a tyjie [holotypt-]. It should, 



* Tlu" following and other dci'mitions may hv found in " Catalogui' of 

 Type Specimens of l-ossil luveitelnates in the Dept. of Geolof»y, n.S. 

 Nat. Mus.." by Chas. Scliiichert, Hull. No. 53, pt. i. (1905). 



