LITERATURE. 83 



that the origin of the efferent genital ducts is to be traced to the nephridia 

 and that they only gradually became separated from these latter organs. 

 Among the Lamellibranchs, processes may have taken place similar to those 

 in certain Annelida (Ciapitellidae), in which new ducts are developed out of the 

 nephridia for the genital products. Such a modification of the nephridia 

 which originally served for conducting the genital products would be explicable 

 as a consequence of the modified function of the coelom and the shifting of 

 the genital glands thus brought about.* 



LITERATURE. 



1. Barrois, Th. Note sur l'embryogenie de la Moule commune 



(Mytilus edulis). Bull. sci. Nord France, (ii.) 2 'annee 

 (1879 ?)• 



2. Barrois, Th. Le stylet cristallin des Lamellibranches. Revue 



biol. Nord France. Tom. i. 1889. 



3. Blochmanx, F. Eine freischwimmende Muschellarve im siissen 



Wasser. Biol. Centralbl. Bd. xi. 1891. 

 . \. Braun, M. Postembryonale Entwicklung von Anodonta. Zool. 

 An::. Jahrg. i. 1878. 



5. Braun, M. Die postembryonale Entwicklung der Najaden. 



Nachrichtsbl. Deutschen Malakozool. Gesellsch. Frankfurt a. M. 

 Jahrg. xix. 1887. 



6. Brooks, W. K. The development of the oyster. Studies Biol. 



Lab. Jolt//* Hopkins Unio., Baltimore. Vol. i. 1880. 



7. Butschli, 0. Xotiz zur Morphologie des Auges der Muscheln. 



Festschrift naturhixt.-med. Vereins Heidelberg. 1886 



8. Carriere, J. Die embryonale Byssusdriise von Anodonta. 



Zool. Am. Bd. vii. 1884. 



9. Carriere, J. Ueber Molluskenaugen. Archiv. f. mil.-ro.Anat. 



Bd. xxxiii. 1889. 



10. Dall, W. H. Report on the Mollnsca (collected by the U. S. 



Steamer Blake). Bull. Mus. Camp. Zool. Harvard. Vol. 

 xviii. 1889. 



11. Ehrenbaum, E. Untersuchungen uber die Structur und Bil- 



dung der Schale der in der Kieler Bucht haufiger vorkom- 

 menden Muscheln. Zeitschr. f. miss. Zool. Bd. xli. 1885. 



* A summary of these points which have been established chiefly by Lacaze- 

 Duthiers and v. Jhering will be found in No. 24, by the last-named author, 

 as well as in Bronx's Klassen und Ordnungen der Thierreichs, Bd. iii., Abth. 

 i. Pelsenkeu has also recently given an account of these conditions. 



