3 54 Prof, M^Litosli's Notes from the 



fiiise less definitely tlia'ii iii C. teniaculatus, it being difficult 

 to say whether they are mainly opposite the sixth or the 

 seventh bristles, whereas in the other they resemble more 

 closely those of C. tentaculatu^ in transverse arrangement 

 and tbey arise opposite the fifth pair of bristles. In both a 

 branchia springs in front of the dorsal of the first series of 

 bristles. The first ventral hooks occur on the thirtieth 

 bristled segment on the right in the example first referred 

 to, and the first dorsal hooks on the forty-first ; whereas in 

 the other specimen, with the groups of tentacles opposite 

 the fifth bristles, the first ventral hook occurs on the nine- 

 teenth bristled segment and the first dorsal hook on the 

 thirty-seventh. These hooks are slightly less curved toward 

 the tip than those of the northern form, but otherwise are 

 similar. The bristles are also proportionally larger, 



A form approaching Cirratulus filigerus, D. Chiaje, from 

 IMalahide, Co. Dublin, obtained by the Royal Irish Acadeniy^s 

 Expedition, is smaller than the foregoing species and 

 presents certain differences. It is 3-4 inches in length, but 

 of similar sha{)e, the anus being dorsal, with a short cone 

 beneath. Immediately behind and rather above the first 

 bristled foot is a branchia, and so uith the three following. 

 On the dorsal sulcus between the fourth and fifth biistle- 

 tufts is a group of four or five slender branchise. Behind 

 the foregoing the branchiae occur on each side and are 

 sparsely distributed along the posteiior region almost to the 

 tip of the tail. The crotchets (hool<s) appear in the ventral 

 division about the twentieth bristled segment, whilst they 

 occur in the dorsal division about the fortieth. Their curves 

 are somewhat more pronounced than in C. tentacnlatus , and 

 in the posterior region the ventral are considerably larger 

 and stronger than the dorsal. 



The third form is Cirratulus cirratus, O. F. Mtiller, which 

 is generally distributed round the shores of Britain between 

 tide-marks. The head is broader than in C. tentaculatus, 

 hoof-shaped, but with a slight notch in the centre, and with 

 two well-marked bands of eyes sloping obliquely outward 

 and backward. The body is 3 to 4 inches in length and has 

 about 106 segments, more distinctly outlined than in 

 C. tentaculatus, and their antero-posterior diameter is greater. 

 It is rounded dorsally, somewhat flattened ventrally, where a 

 deep groove runs from the first bristled segment backward to 

 the tail, which ends in a point or papilla ventrall}', with the 



