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Transactions. 



larger in tlie region of the areola, with an irregular row of rather smaller 

 ones near the posterior and external margins, and between these two 

 rows are a few intermediate in size (figs. 1 and 2). Seen under the micro- 

 scope, the concealed area, which appears smooth to the naked eye, is 

 formd to be covered with roimded tubercles, constricted at their bases, 

 and terminating in 2-3 points (fig. 3). The exposed surface also between 







-->n1. 



■^'^ 



ii 



<:^ 



5b 



Fig. 1. — ^An elytron, enlarged, drawn under a dissecting-lens, freehand, a, the anterior 



margin ; e, external ; m, the mesial, or internal ; p, posterior margin. 



Between the letters a and e are seen the rows of cylindrical hair-like papillae 



on surface. 

 Fig. 2. — A portion of the posterior and external margins (camera, X 10). e, the external 



margin. The outline of the " areola," or area of attachment, is indicated 



by the dotted lines. The whole surface of the elytron is covered with 



small tubercles, which are shown only towards the external margin. 

 Fig. 3. — A portion of the anterior surface of an elytron ( X 17), showing the gradual 



development of the spinose tubercles from the simpler conical ones. This 



seems to be characteristic of the genus. 

 Fig. 4. — Two consecutive parapodia (enlarged), showing the arrangement of the papulae. 



c, cushion at the cirriferous segment ; el, elytrophore. 

 Fig. 5. — The prostomium ( X 4) from above and from the side, merely to show the 



position of the eyes 



the large star-shaped tubercles is covered with numerous small 

 transparent smooth papillae. Further, the anterior region of the 

 surface a little anterior to the excavation of the margin is densely 

 with long hair-like papillae resembling those of the marginal fringe 

 The parapodial papulae, or gills, are few in number, and rather 

 to detect owing to the poor state of preservation of the worm. 



rounded 

 exposed 

 covered 



difficult 

 for the 



