LITERATURE OF SCAPHOPODA. XI 



occasionally, though rarely, shells are found bored by rapacious 

 gastropods. 



Only in a few places have Scaphopods been utilized by man. The 

 aborigines of the Pacific coast used Dentalium pretios^an for currency 

 and also for personal adornment. D. lessoni seems to be used for 

 ornament by the natives of New Guinea ; and there are probably 

 other like instances among primitive peoples. 



LITERATURE OF SCAPHOPODA. 



All that has been written about Scaphopoda from the system- 

 atic standpoint may be divided into two parts : First, a period of 

 more or less crude and largely unsystematic attempts to define 

 species, beginning with Aldrovandus, continued by Linnaeus, 

 ScHROETER, Chemnitz, Gmelin and Lamarck, and second, the 

 period of more fundamental knowledge of the biologic relations of 

 the group, and exact specific definition inaugurated by Deshayes. 



In like manner, the work of Lacaze-Duthiers upon the anatomy 

 and embryology of the Scaphopoda, subdivides the second period 

 into an older and a modern division. 



17.58. Linnseus, in the Tenth Edition of the Systema Natm-ce, places 

 Dentalium between the genera Patella and Serpula. Four species, 

 elephantimmi, dentalis, entalis and minutu [rn] are described. In the 

 Twelfth Edition, aprinum, cornemn, politum and eburneum are 

 added. 



In the Thirteenth Edition, Gmelin increase the number to 21, 

 mainly by the addition of fossil species described by Schroeter. 

 With inconsiderable additions to the roll of species, the genus 

 remained without thorough treatment until. 



1818. Lamarck, in vol. V of the A nimaux sans Fer^t&res, pp. 341— 

 346, monographed it, recognizing 21 species, several being new. He 

 places the genus among the " Annelides sedentaires," and includes 

 a number of worm-tubes in Dentalium. Part of Gmelin's species 

 are omitted, probably as unidentified. A grouping into striated 

 and ribbed species is made. 



The next work upon Dentalium, passing over that of DeFrance 

 in Dictionaire des Sciences Naturelles, 1819, mainly a complication, 

 is: 



1825. Deshayes, Anatomie et Monograjjhie du Genre Dentale, in 

 Memoires de la Societe d'Histoire Naturelle de Paris, ii, pp. 321- 

 378. In this essay the systematic study of these animals was estab- 

 lished as a science. While before they had been placed indifferently 



