20 



Catalogue of Chaetopoda 



sidered ; no doubt the genus Arenicola would have been described 

 under the Ariciea had the work on these lines been continued. 



The classification of the Polychaeta followed by most writers from 

 1865 onwards was that of Audouin and Edwards and of Quatrefages, 

 that is, the order was subdivided into Errantia and Sedentaria. A 

 considerable number of writers, no doubt finding difficulty in deciding 

 whether certain families or genera ^ should be referred to the Errantia 

 or to the Sedentaria, discarded these sub-orders, and, like Malmgren, 

 for instance, adopted the plan of placing the families in such 

 sequence as seemed to them to indicate best their relationships to 

 each other. 



Dr. Levinsen ^ ranged the " Annulata " in three main divisions 

 — Chaetopoda, Gymuocopa (for Tomoptcris) and Discophora (Leeches). 

 The Chaetopoda were divided into Polychaeta and Oligochaeta. 

 Dr. Levinsen grouped the families of Polychaeta so as to form 

 eleven sub-orders, which, however, he did not define. These sub- 

 orders and their families were arranged thus : — 



Phyllodociformia. 



(1) P. vera. 

 Pliyllodociclae. 

 Alciopidae. 



(2) Nephthydae. 



Euniciformia. 



(1) E, vera. 

 Eunicidae. 

 Onuphidae. 

 Lunibrinereidae. 

 Staurocephalidae, 



(2) E. glycerina. 

 Goniadidae. 

 Glyceridae. 



Maldaniformia. 



Maldanidae. 

 Capitellidae. 



Aphroditiformia. 



(1) A. vera. 

 Aphroditidae. 

 Polynoidae. 

 Acoetidae. 

 Sigalionidae. 



(2) PaJmyridae. 



Syllidiformia. 



Sternaspiformia. 



Sternaspidae. 



Amphinomiformia. 



(1) A. vera. 

 Amphinomidae. 

 Euphrosynidae. 



(2) A. arenicolina. 

 Telethusae. 

 Scalibregmidae. 



(1) S. vera. (2) S. spionina. 



Nereidae. Spionidae. 



Hesionidae. Chaetopteridae. 



Syllidae. Cirratulidae. 



Nerillidae. Ariciidae. 



Sphaerodoridae. Chloraemidae (?). 

 Ophelidae ('?). 



Ammochariformia. Hermelliformia. 

 Ammocharidae. Hermellidae. 



Terebelliformia. 



Terebellidae. 



Ampharetidae. 



Amphicteuidae. 



Sabelliformia. 



Sabellidae. 

 Serpulidae. 



' Arenicola, for instance, was placed by some authors in the Errantia, by 

 others among the Sedentaria. The Ariciidae presented a similar difficulty. 



" " Syst.-geog. Overs, nordiske Annulata," etc., in Vid. Medd. naturh. Foren. 

 Kjpbenhavn 1882 (1883), p. 180. 



