250 



Annelida CJwetopoda 



back of the origin of the tentacles are two fans of setae, 

 shorter than those on the next segment, but otherwise 

 similar to them. Each fan has a little rounded lobe back 

 of it. These lobes are close together, similar to each other 

 and to the ventral lobes generally, but smaller. The 

 second segment bears a pair of short branchiae, which in- 

 crease in length on the following segments, till they nearly 

 touch each other across the back. The anterior branchiae 

 bear afoliaceous lobe, with a short, free, rounded extremity 

 (f. 104). This lobe is at first divided into two by an in- 

 cision reaching nearly to the branchia ; the lower lobe 

 being double the length of the upper one. Further back 

 the incision disappears, while the free portion of the lobe 

 becomes longer and pointed (f. 105). 



Ventral rami. On the anterior feet the ventral ramus 

 is a rounded lobe of the same structure as the branchial 

 lobe. At about the 25th segment, this lobe is nearly 

 divided into two by a deep incision (f. 106) ; further back 

 this division becomes complete (f. 107) leaving a squarish 

 lobe between the dorsal and ventral rami, not attached to 

 either. The setae project in front of the lower lobe. On 

 the anterior feet the dorsal setae fall a little short of the 

 outer margin of the lobe ; afterwards they project slightly 

 beyond it. They are numerous, arranged in a fan, delicate, 

 bilimbate, the margins befng very narrow. The anterior 

 ventral setae are like the dorsal (f. 108). At about the 

 25th segment a few bidentate setae, with a broad membrane 

 extending about one-third of their length, replace some of 

 the double-margined setae of the ventral ramus (f. 109). 

 Still further back the bilimbate setae disappear entirely from 

 the lower ramus, being replaced by narrower setae with a 

 single margin (f. 110). 



Description and figures from alcoholic specimens. Pos- 

 terior segments not seen. Segments remaining, 40. 



Length, 20°^; diameter, 15°^°^. 



