ON DINOPHILUS GIGAS. 259 



witb fine cilia, and with stiff sense hairs, the latter being 

 especially prominent in a pair of patches at the anterior end 

 (fig. 1, s. h.). On the dorsal aspect of the head are two bright 

 red, kidney-shaped eyes. A small pair of ciliated pits, such as 

 are described by Korschelt, M'Intosh, and Hallez was observed 



(fig. 1, c.^O- 

 The second segment bears on its ventral surface the mouth, 



which is an elongated slit, bounded by a number of slight folds, 



which are richly ciliated. 



The six following segments are tolerably uniform in diameter, 

 each in the extended condition being slightly dilated in the 

 centre, and separated from its neighbour by an exceedingly 

 shallow constriction. 



Behind the last segment the body narrows suddenly, forming 

 the tail. 



The "segmentation" of the body is only conspicuous in the 

 fully extended condition. By contraction the whole of the 

 dorsal and ventral surfaces become uniform, and the very 

 slightest indication on the sides alone remains to indicate the 

 series of swellings and constrictions referred to. Fig. 3, drawn 

 from a specimen which had contracted under the influence of 

 corrosive sublimate, but which was not in any way otherwise 

 distorted, shows this.^ 



The prse-oral lobe, the ventral surface of the body, and the 

 tail are uniformly covered with short vibratile cilia, and in each 

 segment the cilia are continued into a band which surrounds 

 the animal, while behind the cilia of each segmental ring is a 

 circlet of fine sense hairs (fig. 1, s. h.). Sensory hairs were 

 also specially conspicuous on the tail. 



The pigment granules and numerous oil-globules in the skin 

 rendered the creature so opaque that little could be made out 

 in the living state, except the outline of the highly- coloured 

 stomach (fig. 1, st.) and the mouth (m.). 



The three species of Dinophilus, possessing a brilliant yellow 

 pigment, which have hitherto been described, are D. vorti- 



' Only six post-oral ciliated rings are visible in this figure. I have noticed 

 the absence of the seventh in one or two preserved specimens. 



