LITERATURE OF SCAPHOPODA. Xlll 



attempted, but a general sequence from smooth to ribbed forms is 

 followed. This is the first monograph from which non-molluscan 

 dentaloid forms are rigidly eliminated. The figures are excellent ; 

 and the main criticism we would make upon the text is that there is 

 not enough of it. A few species of earlier authors are incorrectly 

 identified, and those unknown in English collections are omitted; 

 but these blemishes are traceable to the general condition of con- 

 chology and the condensed plan of the Thesaurus, rather than to 

 any lack of care on the part of the author, whose work on Dentalivm 

 has been of very great value to all subsequent workers. 



1872. Much of the same matter, and copies of the same figures 

 were incorporated by Mr. Sowerby in his monograph of the genus 

 in the Conchologia Iconica, Volume XVIII, pis. 1-7, with the same 

 number of leaves of text. A few additional species are figured, but 

 the lithographic plates are poor, doing but scant credit to Mr. 

 Sowerby's pencil. 



1880-1895. Numerous contributions to the general morphology, 

 histology and embryology of Scaphopoda have appeared since 1880. 

 The more extensive and important memoirs being mentioned below. 

 During the same period two extensive reports upon deep sea Scaph- 

 opods appeared : 



1886. K. BOOG WATSON, Challenger Rep., Vol. xv, pp. 1-24. 28 

 new species are described and figured, and a number of those des- 

 cribed by Jeffreys and others are further elucidated. 



1889. WM.H.DALL, Blake Rep., pp. 418-432. 22 new forms are 

 described, with valuable notes on some of the previously known spe- 

 cies. In Trans. Wagner Free Institute of Science, iii, pp. 435-446, 

 the American Tertiary species are discussed ; further information is 

 given on some living forms, and the value of conchological charac- 

 ters in classification is considered at some length. 



1883. A. KOWALEVSKI, Etude sur I'ernbryoge'nie du Dentale. 

 Ann. Mus. d'Hist. Nat. Marseille, I. 



1885. H. FOL, Sur Panatornie microscopique du Dentale, in 

 Arch. Zool. Exper. et Gener. (2), vii, pp. 91-148. 



1892. L. PLATE, Ueber den Bau und die Verwandtschaftsbezie- 

 hungen der Solenoconchen. Zool. Jahr., Abth. fiir Anat. 

 u. Ontog., v, p. 301-386. 



1892. P. PELSENEER, La Classification generate des Mollusques. 

 Bull. Scient. France et Belg., xxiv. 



1891-1894. C. GROBBEN, Verhandl. der d. zool. Ges., 1891, p. 

 63 ; also Sitzber. k. Akad. Wiss., Wien, 1894, p. 61. 



