306 Pi of. M'lntosU's Notes from the 



setigerous segments iu the anterior region and in having 

 simple tips to the compound bristles. It differs in the 

 presence of a slender spine in the first setigerous segment, in 

 the shape of the terminal pieces of the anterior bristles, 

 in the occurrence of simple dorsal bristles in all the seg- 

 ments, in having three anal cirri, and in other details. 

 These differences, however, require further investigation. 



StreptosylHs bidentata, Southern, is characterised by the 

 broad head, four large eyes with lenses, the median tentacle 

 arising between the anterior pair, the palps fused at the 

 base, invisible from above, and with slender papillae on their 

 tips. The body is minute — about 2'5 mm. Proboscis short 

 and broad, proventriculus with forty-five rows of glands. 

 The feet of the six anterior segments differ from those 

 behind. The foot has dorsally a simple bristle, winged and 

 curved distally. The compound bristles are short, thick, 

 and the ends of the shafts liave three or four blunt teeth, 

 whilst the terminal pieces are bifid and coarsely serrated. 

 The structure of the simple, serrated, winged bristle recalls 

 that of Staurocephalus. It differs from S. varians in the 

 length of the proboscis and proventriculus, in themoniliform 

 condition of some of the dorsal cirri, in the larger palps, in 

 the minute structure of the bristles, and in the greater 

 number of the anterior segments with thick spines. It 

 differs from S. websteri in having six segments in the 

 anterior region and in the structure of the bristles 

 ■ (^Southern). 



In Opisthodonta pterochata, Southern, the palps are free 

 distall}', but united at the base. The buccal segment has 

 two pairs of tentacular cirri, all cylindrical and smooth. 

 The body is more than 6 mm. long and has forty-nine 

 segments, the pharynx stretches through sixteen segments 

 and has a sharp lateral tooth about its middle, the proventri- 

 culus has forty-five rows of glands. The bristles have 

 enlarged spinous ends to the shafts and simple curved 

 tips. Swimming-bristles occur on the 31st foot. In the 

 middle region the foot is biranious, dorsally having capillary 

 bristles, ventrally a single upper wing«d bristle, four or five 

 compound, and a single bristle without wings below. 



Southern found, on the west coast of Ireland, a mature 

 female of Ehlersia ferruginea, Langerhans, in March, Avith 

 a long tuft of swimming-bristles on the twenty-eighth seg- 

 ment and no sign of a bud, so that it is probable it repro- 

 duces directly and may pertain to Pionosyllis lamelligera, 

 De St. Joseph. It differs from Syllis cornutu, Eathke, in 



