14 • INTRODUCTION. 



are not to be had, then what are we to call the specimen selected for special descrip- 

 tion by the reviser and reestablisher of the species? 



The writer would therefore define a neotype as a supplementary type 

 selected by an author, on which a species is to rest because of the loss 

 of the original type or where the original material still extant is so poor 

 or fragmentary that from it the characters of the species can not be 

 determined with certainty. 



Heautotype (new). — In a letter to the writer, Buckman proposes 

 this term for ' ' a specimen figured by an author as an illustration of his 

 own already founded species such not being a proterotype " (= primary 

 type). The same writer, in 1899, used the term autotype, but as this 

 word is also in use for certain printing blocks he changes it here to 

 heautotype. 



TYPICAL SPECIMENS, OR ICOTYPES. 



Topotype (Thomas). — A specimen collected at the exact locality or 

 within a few miles of the place where the original type of a species was 

 obtained. 



In paleontology it is further demanded that the topotype should come 

 not only from the exact locality but also from the identical stratum that 

 furnished the species. 



Topotypes and metatypes have been wrongly included by CEhlert 

 (Palaeontologia Universalis, 1904) under Schuchert's term " supplemen- 

 tal types" or hypotypes (=plesiotypes). These specimens have not 

 the value of " type material" as here defined, but belong to the cate- 

 gory of ' ' typical specimens. " 



Metatype (Thomas). — "A specimen received from the original 

 locality [in paleontology, the exact stratum as well] after the description 

 has been published, but determined as belonging to his own species by 

 the original describer himself. ' ' (See ideotype. ) 



Metatype has been redefined by Walsmgham and Durrant" as follows: 

 ' ' A specimen subsequently named by the author after comparison with 

 the type is called a Metatype. ' ' As this is not the meaning given by 

 Thomas, it can not be accepted. The latter 6 says: 



The objection to " hypotype " [=metatype] as being too general and covering too 

 many specimens of different origins applies even more strongly to Lord Walsing- 

 harn and Mr. Durrant's proposed extension. Many a museum worker, 



who has to name large series of specimens from all sorts of localities, must constantly 

 put under one of his own names specimens which may be anything but typical, and 

 it would be absurd to call the whole of a museum series of a common animal " meta- 

 types" merely because the name of the species happened to have been proposed by 

 the person who determined the specimens. 



Homceotype. — Under the name homotype, Walsingham and Dur- 

 rant define this term thus: "A specimen named by another than the 

 author, after comparison with the type, is called a Homotype." How- 



aMerton Rules, London, 1S96 p. 13. 6 Science, Sept. 24, 1897, p. 486. 



