INTRODUCTION. 17 



NecroTypes {dead and /on//): Forms formerly existing in a country but now 

 extinct; e.^-,^ the horses and rhinoceroses are necrotypes of North America, indig- 

 enous species having once flourished on that continent, but become exterminated 

 in prehistoric [or previous geologic] times. « 



The CenUtry Dictionary defines this term thus: "A type formerly 

 extant in any region, afterwards extinct; thus, indigenous horses and 

 rhinoceroses are necrotypes of North America." 



MARKING OF TYPE MATERIAL. 



All type material should be plainly and permanently marked to di.s- 

 tini^uish it from other .specimens. If this is carefully done, nuich doubt 

 will be removed for subsequent students. When such material is large, 

 as birds and mammals, a small highly colored card or a piece of plain 

 zinc may be attached, upon which should be printed or .stamped the 

 proper term indicating the kind of type and the nuiseum catalogue num- 

 ber. In paleontology, it is the cu.stoni to glue small red or green dia- 

 mond or star-.shaped tickets upon the type material, in addition to the 

 catalogue number, when sufficiently large to permit of this without 

 covering too nnich of the specimen. The .small specimens are placed in 

 numbered vials or in boxes. In the Woodwardian Museum (Cambridge, 

 England), type fossils are mounted on blue tablets. This arrangement, 

 however, has the disadvantage of giving the exhibition .series a checkered 

 appearance, and should the specimens become loosened and displaced 

 there is danger of the types being overlooked. 



LITERATURE ON TYPE TERMS. 



B.\THER, F. A. — A postscript on the terminology of types. vScience, May 28, 1S97, 

 pp. 843-844. 



BuCKM.\N, S. S. — List of t3-pes and figured specimens of Brachiopoda. Proc. Cottes- 

 wold Nat. Field Club, XIII, Dec, 1899. 



COvSSMANN, M.\URiCE. — Essais de Paleoconchologie comparee, 1896, pp. 2, 3. 



. — Revue Critique de Paleozoologie, April, 1904, pp. 73, 74. 



CouKS, ElijoT. — On some new terms recommended for use in zoological nomencla- 

 ture. Auk, IX, 1884, pp. 320-322. 



Gill, TheodORb: N.— Zoology. Ann. Kept. Board Regents vSmilh.sonian Institution 

 for the year i88r [1S83], p. 460. 



MAR.SH, O. C. — The value of type specimens and importance of their preservation. 

 Amer. Jour. Sci., VI, 1898, pp. 401-405. 



MERRIAM, C. H.\rT. — Type specimens in natural history. Science, INIay 7, 1897. 



pp. 731-732. 

 CEhlerT, D. p. — Palaeontologia Universalis. Note, 1904. 

 Palmer, T. S.~ Index Generum Mammalium. North American F'auna, No. 23, 



1904, U. S. Dept. Agriculture, Div. Biol. Surv. 

 SCHUCHERT, Charles.— What is a type in natural hi.story? Science, April 23, 1897, 



pp. 636-640. 



"Gill, Smithsonian Report for 18S1 (1S83), p. 460. 

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