EITNOA NODOSA. 293 



are subulate organs marked by six rows of conical papillae, which become larger 

 towards the tip of the organ. 



Body large and broad, somewhat more rounded dorsally than ventrally, slightly 

 tapered anteriorly, very gradually but much more tapered posteriorly. Dorsally, it is 

 readily separated from other allied genera by the presence of the peculiar expansion 

 at the base of the dorsal cirrus. The bristled segments are thirty-six in number. The 

 shorter dorsal bristles at once distinguish the species when compared with E. oerstedi. 

 Dorsally, the segments are generally marked by a transverse bar often dimpled at the 

 outer edges, and by irregular papillae internal to the scale-bearing process. Ventrally, the 

 usual median groove marks the centre. 



Posteriorly the body terminates in two caudal styles, which have a similar structure 

 to the cirri. 



None of the spirit preparations show colour along either dorsal or ventral surface, 

 except a few touches on the area below the median and lateral tentacles; thus the species 

 is in contrast with E. oerstedi. The only pigment visible consisted of a brownish 

 hue on the lateral tentacles, and a brownish ring below the dilated region of all the 

 cirri. 



Proboscis. — No example of E. nodosa has an extruded proboscis. E. oerstedi shows 

 nine dorsal papillae and nine ventral, and the teeth are powerful. In E. oerstedi three 

 gastric caeca pass forward to the dorso-lateral wall of the peripharyngeal space, the 

 fourth being nearly transverse. The longest is the ventral, which forms a narrow tube 

 anteriorly and extends to the fourth segment in front of the stomach. The posterior 

 half, however, is widened by two or three sacculations at its outer edge. The second 

 and third are shorter and wider clavate caeca, terminating in the corresponding spaces 

 behind the first. The stomach, if we may so term the anterior dilated part of the 

 intestine, has thick muscular walls, and its inner surface has a closely arranged transverse 

 series of firm glandular lamellae, interrupted at short intervals, so as to be crenate or 

 papillose. These ridges become less and less distinct as we proceed backwards, until 

 towards the vent the thin wall shows only the distinctly isolated papillae as in Halosydna 

 gelatinosa. It might be considered that the foregoing appearances of the stomach were 

 due to the condition of the preparation, but such did not seem to be the case. 



The external opening of the segmental organ has no papilla, but is marked in 

 E. oerstedi by a blackish pigment-speck. In one example two specks were present on a 

 posterior foot. The genus thus diverges from HarwMhoe. 



Scales. — The scales (Plate XXXII, fig. 3) of this form are distinguished from 

 E. oerstedi by their more leathery consistence, by their characteristically reniform 

 outline, by their longer and more abundant cilia on the outer edge, and by the 

 divergent character of the tubercles, which are much more developed in E. oerstedi. The 

 anterior scales, as usual, are rounded, but the typical scales are reniform with the free 

 parts studded with small horny tubercles and a row of from six to nine much larger 

 blunt horny tubercles, or short cones, some of which, a little within the posterior border, 

 present a bluntly spinose condition at the tip. The anterior and inner margins are smooth, 

 while along the posterior border a few isolated short cilia occur, gradually increasing in 

 length till they terminate at the outer edge in the long cilia with the clavate tips. In 



