REPORT OF THE STATE PALEONTOLOGIST 1902 1237 



Along the lateral margins are broad free fringes like matted 

 bunches of setae which may attain a length of nearly or quite 

 half the width of the body. All the specimens show this char- 

 acter but in one only do these present the aspect of a continuation 

 near the posterior extremity of the edges of the dorsal scutes. 

 One could conceive the thickenings of the margin by the sub- 

 marginal ridges as due to the parapodia. 



The marginal filaments are usually directed backward, though 

 they may turn for Avar d toward the anterior extremity. 



The cast of the other, or ventral surface simply presents these 

 various details of structure with some obscurity. 



These characters seem throughout so suggestive of the features 

 shown by Aphrodite and Polynoe that we shall probably not be 

 far amiss in associating these forms therewith ; if not in direct 

 association, at least Avith the Errant worms. For a designation 

 therefore, we propose to indicate these objects as Pro- 

 tonympha salicifolia. 



2 The second series of these annelids is composed of much 

 more elongate bodies like Phyllodoce or Nereis and are usually 

 curled up in spirals. These are rather blunt at one end, main- 

 tain a somewhat uniform width for most of their length but taper 

 thence to a narrow extremity. The bodies are distinctly seg- 

 mented, in the best preserved of the specimens there 'being 

 upward of 100 narrow divisions which are separated from each 

 other by tolerably deep depressions. In the axial line is a 

 furrow which so divides the segments as to give each the ap- 

 pearance of being in two parts. It is not evident that these 

 segments were plated but the impressions which they leave in 

 sandy sediments seem to indicate this as a possible eonfMiion. 

 Each however bears at each margin a parapodium carrying a 

 bunch of long setae making a fringe often wider than the body 

 itself, and into these parapodia the segments seem to extend 

 without interruption. The general expression of this structure 

 is very like that of the long row of posterior segments in Chaetop- 

 terus and there is also a notable similitude between the arrange- 

 ment of the segments in the latter and that shown at the broad 

 extremity of the fossil in question, and furthermore in the clear 

 development of the median part represented by the axial line in 



