EUNOA NODOSA. 291 



to the Gulf of St. Lawrence. Finally, Malaquin (1890) describes a variety found in the 

 tubes of Ghxtopterus at Boulogne. 



Genus X. — Eunoa, Malmgren, 1865. 



Lateral tentacles arising under the median — below and slightly internal to the peaks 

 of the head. Palpi with six rows of short cilia ; eyes large, visible from the dorsum. Three 

 intestinal caeca directed forw r ard into the peripharyngeal space, the ventral long and 

 narrow, with two or more sacculations at its outer border inferiorly. The other two are 

 clavate and short. Elytra, fifteen pairs, completely covering the dorsum, and occurring on 

 the first foot, third, fourth, sixth, eighth, and so on to the twenty-second, twenty-fifth, 

 twenty-eighth, and thirty-first. Dorsal bristles pointed at the tip (which is bare), then 

 minutely spinulose in rows ; ventral bristles somewhat longer, and resembling those of 

 Harmothoe, with a smooth tip, which has a hook and transverse rows of spikes. 

 External aperture of the segmental organ indicated by blackish pigment ; no papilla. 



Note. — This genus approaches Harmothoe, but the peaks of the head in the latter are 

 close to the median tentacle, whereas an interval exists in Eunoa. The eyes in 

 Harmothoe are smaller and less visible, the anterior pair being under the point of the 

 peak, whereas the anterior pair of Eunoa are situated some distance backwards, and are 

 lateral in position — not ventral. The bristles of the first foot in Eunoa are very distinct. 

 The remarkable Eunoa hispanica, 1 procured by the c Porcupine ' in 1870 on the Channel 

 slope, diverges from the other known forms by the great size of the eyes (with their 

 corneal lens), which exceed by far those of any other example of the family, by the great 

 length and smoothness of the palpi, and the great length of the ventral cirri and the 

 foot. The dorsal cirri probably have no enlargement below the tip, if we may judge from 

 a single lateral tentacle. E. hispanica is scarcely within the British area, but it is 

 worthy of note in this connection, and may yet be found near the coasts. 



1. Eunoa nodosa, M. Sars, 1860. 



Specific Characters. — Body broad, flattened, slightly narrowed in front, but much 

 more gradually and distinctly posteriorly; bristled segments, 36; head about as broad 

 as long, with a deep notch in front, from which the peaks are clearly marked off on each 

 side ; eyes large, two anterior to the nuchal fold, and two just in front of the lateral 

 projection of the head, and thus considerably behind the peaks ; tentacle ciliated, slightly 

 dilated below the slender tip, longer than the palpi — in preservation ; lateral tentacles 

 short, of similar shape ; palpi subulate, with six rows of minute papillae ; tentacular 

 cirri smaller than the tentacle, but of similar structure; scales, 15 pairs, completely 

 covering the dorsum, with the exception of the first pair, elongate reniform and some- 

 what thick, external margin densely ciliated, exposed surface rather thickly covered with 



1 ' Trans. Zool. Soc./ ix, p. 396. 



