424 THE ANNELIDA POLYCHAETA. 



Eupista Mcintosh is preoccupied by Eupista Hiibner (1816). It is here 

 replaced by Eupistella, nom. nov. 



TeHebella Linne. 



Syst. nat. ed. 12, 1767, 1, p. 1092; St Joseph, Ann. sci. nat., 1894, ser. 5, 17, p. 181, 202. 



Leprea Malmgren Ofvers. K. vet. akad. Forh. 1865, 22, p. 389; Marenzellhr Sitzungsb. K. akad. 



sensch. Wien, 1884, 89, p. 179. 

 Heteroterebella Quatrefages, Hist nat. anneles, 1865, 2 p. 384. 

 Heterophyselia Quatrefages, Ibid., p. 386. 

 fSchmardanella McIntosh, Challenger Annelida, 1885, p. 449. 



Terebella panamena, sp. nov. 

 Plate 79, fig. 7, 8. 



General color throughout light yellow, the dark contents of the alimentary 

 canal showing through the walls in the caudal half. 



The body narrows very slightly caudad excepting at the extreme end, which 

 is narrowed subconically to a narrowly rounded point. Thorax not set off from 

 abdomen by difference in width. The greatest width of the thorax is in the 

 type 2.2 mm., the middle region of the abdomen being but Uttle narrower, 

 about 2 mm. The total length, exclusive of the tentacles, is 30 mm. Length of 

 the tentacles about 8 mm. The total number of somites is close to ninety-two. 



The tentacles are numerous, proportionately moderately coarse, and 

 channeled longitudinally in the usual way. 



The peristomium is a complete ring which is especially large laterally and 

 ventraUy. The ventral lobe is transversely elongate, clearly wider than the 

 ventral plates excepting that of the second somite, with the anterior edge straight 

 and the ends convex. It is much longer than the ventral plates and is bowed 

 ventrad. 



There is neither ventral nor lateral flap on the third somite. The second 

 somite presents a ventral plate as wide as the lip-lobe of the peristomium, with 

 its anterior margin convex. It is decidedly wider and longer than the ventral 

 plate of the third somite, the anterior and lateral edges of which are straight. 

 The first two ventral plates together flare ventrad below the level of the other 

 plates. 



There are two pairs of branchiae, which are dwarfed and have comparatively 

 few branches. 



The precise number of setigerous somites cannot be determined, but seems 



