312 ACAXTHICOLEPIS ASPERRIMA. 



median groove, which trends outward in front to terminate in the peaks on each side of 

 the median tentacle. The eyes are large and black, two being situated a little in front 

 of the nuchal fold, and slightly lateral in position, and two in front of the lateral 

 projection of the head, and also more or less lateral in position. Both pairs are thus 

 only fully seen in side view. JMo example has a median tentacle. The lateral tentacles 

 arise under its base, and are short organs with a trace of an enlargement below the 

 slender tip, and somewhat closely ciliated. The palpi, which are of moderate length, 

 show minute cylindrical papilla in certain parts, but seem to be mostly smooth! 

 Segmental papilla slender and somewhat long anteriorly, short posteriorly; directed 

 upwards between the feet. 



Body flattened and proportionally broad, slightly narrowed towards the head, and 

 more distinctly posteriorly, where it is terminated by the two subanal cirri. The dorsum 

 presents no feature of note. Ventrally the segmental papilla is slender and small, 

 arising from an elevation close to the posterior border of each foot. These rounded 

 elevations form a moniliform series along each side of the body. The cirri are 

 comparatively slender and short. 



The colour in the spirit-preparations has mostly disappeared, only one showing a 

 few brownish transverse bars anteriorly on the dorsum, and a slightly brownish hue on 

 the anterior folds of the mouth. The palpi have a curious greenish-grey colour, while a 

 trace of brown remains on the cephalic appendages, the dorsal cirri, and the first (long) 

 ventral cirrus. The anterior scales are brownish grey, with the brown spines standing 

 prominently outward. 



Scales (Plate XXXII, fig. 4). — The first pair are more or less rounded, and studded 

 chiefly at the margin with the horny spines, the intervening spaces being often coated 

 with mud and parasitic growths. The scales generally are by no means thick, but are 

 covered with the chitinous papilla or bosses, small towards the anterior edge, but rising 

 into the long spinous processes posteriorly (Plate XXXIII, fig. 3). These processes 

 terminate in a bifid, trifid, quadrifid, or quinquefid tip. , The central axis of each is 

 cellulo-granular. From the inner to the outer margin also a few slender cilia with 

 clavate tips are present. The majority of the scales are more or less reniform, but 

 posteriorly the last pair become ovoid, with the same structure of spines and cilia. 

 The under surface is smooth and iridescent, with the scar for attachment somewhat 

 nearer the anterior than the posterior border, and more distant from the inner than 

 the outer margin. The scales are easily removed. 



Feet. — The first (with the tentacular cirri) has three bristles, which conform to the 

 type of the dorsal bristles, only they are proportionally shorter and more curved. 



In the second foot the dorsal bristles are stout and have boldly marked spinous rows 

 which in lateral view follow slightly oblique lines across the shaft. They are formed 

 by a thin chitinous plate split into the spines or teeth, somewhat after the fashion of the 

 ctenidial rows in Pleurobrachia, and increase in size from the dorsal to the ventral 

 surface of the bristle. The terminal region of the bristle is smooth. The ventral 

 bristles are very slender, with long tips having alternate spinous rows, the extremities 

 being slender and slightly hooked. The long ventral cirrus has moderately long clavate 

 cilia. 



The usual gradations occur till the typical foot is reached (Plate XLII, fig. 29). 



