EUNICIDAE 



119 



on the 5th) segment and end between the 40th and 45th segments. Very rarely they 

 are continued to about the 60th chaetiger. They are at their maximum development 

 between the 20th and 30th chaetigers, where they are usually composed of 7-8 filaments. 

 One large specimen from St. 152 has as many as 15 filaments. The acicula are yellow, 

 as is also the hooded bidentate subacicular chaeta which begins between the 30th and 

 35th chaetigers. The comb chaetae have the lateral tooth of one side much elongated. 

 There are two pairs of pygidial styles, the upper long and the lower very short. 



The anterior edge of the lower jaw plates (Fig. 42, a) is calcareous and irregular, often 

 with three more or less distinct teeth. 



3 mm 



T2mm 



O 



a 



^O 



Fig. 42. Eunice pennata. 

 a. Lower jaw plates, b. Upper jaws. 



The dental formula (Fig. 42, b) is as follows : 8 or 9 — 9 : 9 or 10 + 7 or 8 — 12. Maxilla 

 V is represented by a small chitinous plate. 



These specimens seem to me to be indistinguishable from a rather small example of 

 the uncommon deep water European species. Augener and Fauvel give the length as 

 between 60 and 150 mm. Fauvel gives the number of gill filaments in a fully developed 

 branchia as between 8 and 17, and Augener as between 10 and 22. In these specimens 

 8-15 is the maximum. Fauvel states that the gills cease between the 30th and 46th 

 segments and Augener about the 60th segment. In these specimens they usually cease 

 between the 40th and 45th segments. 



This species is closely related to E. atlantica, Kinberg. 



Ehlers (1901, p. 125) gives an account of a small example of the latter species mea- 

 suring 41 mm. long and with 124 chaetigers. In this the median tentacle reaches back 

 to the 9th segment (7th chaetiger) and the first and second segments are together equal 



