50 EULALIA BILINEATA. 



Marenzeller 1 describes and figures two ciliated lappets on the head (one on each 

 side). They are single in front, bifid behind. He therefore considers the' A", alatum of 

 Langerhans to be the same form, especially as Levinsen mentions them in the northern 

 species. 



Allen finds this species common in clredgings off Plymouth, but all the examples are 

 small, though adult. Like certain northern forms the size diminishes in southern waters. 



Genus XXXL— Eulalia, (Erstecl, 1843. 



Head furnished with five tentacles, the median arising in front of the eyes. 2 First 

 segment free from the head. Four pairs of tentacular cirri with or without feet beneath 

 (first pair attached to first segment, (Erst.). Dorsal cirri (QErsted's branchiae) arranged 

 in various ways. Ventral cirri nearly horizontal. Cerebral lobes with a special 

 ophthalmic lobe ; median tentacle supplied by two nerves which unite at its base ; 

 s tomato -gastric branches arising from oesophageal connectives (Pruvot). 



Claparede includes Eumida, Malmgren, and Eracia, Be Quatrefages (= Eumida) 

 under this genus. He rather approves of the vagueness of the descriptions of the 

 segments bearing tentacular cirri since it is impossible to fix hard and fast limits 

 to these. 



Grube (1879) defines Eulalia as having the dorsal cirri lancet-shaped or pointed, 

 more or less constricted at the base. 



Sub-genus Eulalia, sans str., Grube, 1879. 

 Dorsal cirri oval- elongate, not pointed. 



1. Eulalia bilineata, Johnston, 1840. Plate XLIII, fig. 5 (var.) ; Plate L — fig. 4, head; 

 Plate LXVII, figs. 6 and 7— foot, etc. ; Plate LXXVII, figs. 23 and 24— bristles. 



Specific Characters. — Head somewhat longer than broad; eyes two, black, placed 

 towards the posterior border of the head. Anterior tentacles subulate, rather short. 

 Median tentacle very short, arising just in front of eyes. Tentacular cirri likewise some- 

 what short — only a little longer than the diameter of the body. Length from one and a 

 half to three inches, the body being tapered anteriorly, and diminished more distinctly 

 posteriorly, where it terminates in two subulate or sometimes clavate cirri. Colour dull 

 yellowish, greenish-yellow, or straw, the proboscidian region of the body being paler. 

 Ventral surface slightly greenish, a pale greenish band, most distinct anteriorly, passing 



1 "Polychast. des Grundes.," c Zool. Ergebn./ ii, p. 7, Taf. ii, fig. 4. 



3 The exceptional position of the median tentacle, viz. at the extreme posterior border of the 

 head, in Ehlers' Eulalia imbricata, is noteworthy. 



