Gatty Marine Lahoratory ^ St. Andrews. 557 



lengcr.' The slenderness of the tips of the bristles of the 

 first foot in the British form is, however, diagnostic. 



The simple dorsal bristles with winged tapering tips are 

 short in the 10th foot_, but become longer in the 20th and 

 posterior feet, and in the latter are accompanied by two 

 strong bifid hooks inferiorly. 



This form approaches Nothria WiUemoesi of the ' Chal- 

 lenger/ yet is distinct in regard to comparative lengths of 

 the median and lateral tentacles and in tiie minute structure 

 of the anterior bristles, which come nearer those of N. Ar- 

 mandi and ^Y. minuta. It appears to be closely allied to 

 the Diopatra [Paradiopatra) fragosa of Ehlers *, taken off 

 Sand Key and other parts of the American shores, though the 

 minute structure of the bristles, the breadth of the peristo- 

 mial segment, the position of the tentacular cirri, and other 

 j)oints require further investigation. The Onvphis quadri- 

 cifspis of Sars has similar bristles on the first foot, but 

 otherwise diverges, e.g. in the presence of brauchicC. 



Those in the second group of the Onuphidse are devoid 

 of tentacular cirri, though it has to be mentioned, as 

 demonstrating the caution necessary in dealing with such 

 characters, that, in an example of Hyalinoecia tuhicola from 

 Norway (Canon Xorman's collection), a well-formed tenta- 

 cular cirrus, arising from the middle of the peristomial 

 segment, occurred. 



The most abundant and widely distributed species is 

 Hyalinoecia tubicola, O. F. Miiller, and it is specially 

 plentiful in Zetlandic and Hebridean waters and oft' the 

 south-west coast of Ireland. The strongly bifid winged 

 falcate bristles of the first foot and the powerful bifid hooks 

 behind are diagnostic. The branchiee commence from the 

 23rd to the 26th foot and continue almost to the last 

 segment. 



The translucent quill-like tube is easily recognized. 



Another is Hyalinoecia sicida. De Quatrefages, a small 

 species which ranges from Shetland, where it was first 

 dredged by Dr. Gwyn Jeffreys, to Connemara on the west 

 and Plymouth on the south. Two parallel bands of brown 

 which course backwards from a transverse belt of the same 

 colour immediately behind the head, and a brown spot 

 between each foot from the 5th backward, readily distin- 

 guish the species even in spirit. Its tube is generally 

 composed of gravel and shell-fragments. 



Of the Eunicids, the Eunice fasciata of Risso (= E. Ha- 

 rassii of Andouin and Edwards) is not unfrequent in the 

 * Christianiafjordens Fauna, p. 16, tab. xv. figs. 7-19. 



