DR. BAIED ON SEVERAL GENERA OF EUNICEA. 341 



margin. Beneath bronzy ; apical segment of abdomen and legs fer- 

 ruginous. 



Head deeply and rugosely punctured. Thorax not quite two-thirds as 

 long as wide at the base ; anterior margin slightly produced in the 

 centre, about half as long as the base ; sides gradually but slightly 

 rounded ; base with a yellow median lobe ; surface deeply and largely 

 punctured, especially at the sides ; dorsal line, and a line parallel to 

 each lateral margin, impressed. Elytra deeply punctate-striate, twice 

 as long as wide ; posterior margins finely and sharply denticulate ; 

 apex of each bidentate. Beneath and legs punctured, covered with 

 long hairs. 



Lcngtli 9^ lines. Breadth 3^ lines. 



Hab. South America. 



Remarks on several Genera of Annelides, belonging to the Grroup 

 Eunicea, with a nobice of such Species as are contained in the 

 Collection of the British Museum, and a description of some 

 others hitherto undescribed. By "W. Baird, M.D., P.E.S., 

 F.L.S., &c. 



[Read February 4, 1869.] 



This group of Annelides contains individuals remarkable for their 

 great length; and, according to M. Quatrefages,some of the species 

 exhibit a complication of structure superior to that of any other 

 of the Annelida errantia. They are of an elongated form, and 

 generally slender, and are composed of numerous articulations. 

 The head is more or less distinctly lobed, and possesses from five 

 to seven organs usually described as antennae or tentacles, and 

 sometimes two tentacular cirri on the dorsal part of the buccal 

 segment. The feet are disposed in one row only ; and the branchiae, 

 which are present in all, are either pectinated and occasionally 

 much developed, or simple and small. The mouth is armed with 

 strong denticulated maxillae. 



This group may be divided into two families, Eunicii)J3 and 



ONUPIUDlDiE. 



Family I. EUNICID^. 



The species of this family are characterized by the head being 

 distinctly two- or four-lobed, by the presence of two eyes, and the 

 possession of five long and filiform organs generally described as 



