Oatty Marine Laboratory, St. Andrews. 161 



Duumanas Bay. 11. 2. 92 iu the collection of the Royal 

 Irish Museum. 



The snout forms a blunt cone, with slight lateral notches 

 which may indicate sensory grooves, and the peristomial 

 segment is devoid of bristles. The mouth opeus ventrally as 

 a large aperture, having a crescentic groove posteriorly and a 

 median furrow between the two lateral lips anteriorly. 

 From the peristomial segment the body gradually widens to 

 the eighth or ninth bristled segment, and then rather 

 abruptly dilates into an ovoid swelling including about ten 

 segments, when it again contracts, such being doubtless due 

 to the mode of preparation. The segments of the anterior 

 region are distinctly marked and one-ringed, and the feet 

 are represented by lateral ridges with dorsal and ventral 

 setigerous processes and a minute flat intermediate papilla. 

 Anteriorlv the feet present, as at the sixth, a long dorsal 

 tuft of capillary bristles and a shorter one ventrally. This 

 arrangement continues toward the thirtieth foot, when a 

 stouter series appear — at first simply modified ordinary bristles 

 with a double curvature of the shaft and a finely tapered tip, 

 the ventral series apparently preceding the dorsal. Finally, 

 posteriorly both divisions have the elongated and charac- 

 teristic hooks. These have long, straight, finely striated 

 shafts, which at the upper part have a slight curve forward, 

 then gently curve forward to the sharp tip. The striae cease 

 about the middle of the tip. They thus differ from the con- 

 dition in Ch(Stozone and approach that in Cirratulus. 



A species (Chatozone zetlandlca) dredged by Dr. Gwyn 

 Jeffreys in 100 fathoms in St. Magnus Bay, Shetland, in 

 July 1867, appears to differ from C/icetozone setosa. It is a 

 fragment about ^ an inch in length of the middle and poste- 

 rior regions, including more than sixty bristled segments, 

 and is distinguished from C. setosa by the flattened body, 

 the more hirsute lateral regions, the button-shaped anus, and 

 the absence of the differentiated posterior region so charac- 

 teristic of the species just mentioned. The broad flattened 

 body has very distinct segments, with setigerous papillae 

 projecting as conical eminences on each side. The posterior 

 end seems to have been reproduced, about fifteen segments 

 being thus added m ith the large button-shaped pygidium ; 

 but the general structure of the feet remains as in front, 

 and it differs from the condition in C. setosa, in which the 

 modification of the crotchets in the posterior region is 

 characteristic. 



Ann. & Mag. N. Hist. Ser. 8. Vol. vii. 11 



