Wl ANNELIDA POLYCHAETA. 



by Claparède in a sense different from what it was in- 

 tended for by its author. 



I prefer to base the subdivisions of the genus Nereis 

 rather on characters taken from the arrangement of the 

 paragnathi , than on the state of development of the dorsal 

 lobe of the feet. The main groups of paragnathi of the 

 proboscis are rather constant and appear not to be liable 

 to much variation in the same species ; moreover the know- 

 ledge of their arrangement enables us to recognize also 

 the systematical position of the Heteronereis- iorms. On the 

 contrary the lobes of the feet are liable to much variation 

 in different regions of the body, and show such marked 

 changes in individuals coming to sexual maturity , that I 

 do not think it advisable to rely much upon their characters 

 for classification. 



Besides the specimens of our Museum , I could also exa- 

 mine the Annelida collected by Prof. E. van Beneden , during 

 his stay on the coast of Brasil, in the Gulf of Rio de Janeiro, 

 and already described by Dr. Armauer Hansen '); I am 

 much obliged to the Director of the Museum of Liège for 

 allowing me to examine them, as Hansen's descriptions 

 are as well very incomplete as inaccurate and our knowledge 

 of local faunas being rather scanty. This interesting col- 

 lection contains two species belonging to the group Peri- 

 nereis, N. ferox Hans, and N. minor Hans.; in the present 

 note I will publish a detailed description of them. Three 

 other species : N. obscura Hans. , N. coerulea Hans, and 

 N, microphthalma Hans., will be shown to be mere synonyms. 



Nereis cultrifeva Gr. 2 ) — Ehlers , Borstenwürmer , 

 p. 461, pi. XXI, figs. 31 — 36. — Claparède, Annélides 



1) Mem. couronnés et Mem. des Savants étrangers de 1' Académie Royale de 

 Bruxelles, T. XLIV, 1882, pi. I— VII. 



2) For the synonymy it may be referred to those authors, who already 

 published a list of them; I think it superfluous to repeat them and I wish 

 to avoid a common fault of our days, rightly characterized by Biitschli as »eine 

 Art Kultus mit möglichst nummerreichen Literaturverzeichnissen". 



JNotes from the Leyden Museum, Vol. XI. 



