360 THE ANNELIDA POLYCHAETA. 



each somite of the second division a low, short ridge or rounded elevation on the 

 anterior side of the somite, this often broken into two tubercles, and commonly 

 purplish in color. In the more posterior somites this ridge is more elongate 

 and lacks any purplish pigment. 



The parapodia of the anterior division are all strongly developed, with both 

 branches conspicuous. They are reduced in size gradually at the anterior end, 

 but in all cases are large and distinct. The neuropodia are strongly elongate 

 in the dorsoventral direction, the distal end linear, or linear oblong, in outline, 

 the remaining part increasing strongly in thickness proximad. They decrease 

 in size both ways from near the middle of the series. The caudal distal edge is 

 slightly raised and, ventrad of its middle, is prolonged into a pointed lobe which 

 is subcorneal, with thick base, or in the more posterior ones becomes more or less 

 flattened and broader, and in the most anterior ones much more slender. The 

 notopodia of the anterior division are much less stout than the neuropodia, from 

 which they are separated distally by a deep and wide cleft. Each bears a 

 large and very conspicuous postsetal lobe, which is broadly subcorneal, being 

 proximally as broad as the notopodium proper, and distally prolonged into a 

 slender tip with incurving sides and acute tip. Each postsetal process has a 

 purplish spot on its middle. In the anterior parapodia of the posterior division 

 the neuropodia are abruptly much smaller than those of the anterior division, 

 being still, however, stouter than the notopodia. Caudad the branches be- 

 come gradually larger and more slender, the neuropodia exceeding the notopodia, 

 with the cleft between ver}^ deep. In the most caudal region of the longer 

 fragment the cleft between the branches becomes very shallow and the noto- 

 podia appear more tubercle-like. The parapodia in this region are much flat- 

 tened in the anteroposterior direction and extend out dorsad and ventrad at the 

 base. No true cirri occur. 



Nearly all the setae of the posterior division of the body have been lost. 

 Those detected are all of a very fine, long, capillary type, with strongly marked 

 cross-striation, or annulation. Those of the notopodia of the anterior parapodia 

 are of the same type. (Plate 65, fig. 2). In the anterior neuropodia, setae of 

 this type occur along with numerous setae of a much stouter, shorter, special 

 type, the setae being very numerous and densely arranged in vertical series. 

 The stout, blade-like setae all have the free portions strongly curved and acutely 

 tipped; the tip curves slightly in the reverse direction. The setae are strongly 

 and closely camerated, or cross-striate, like the finer and more flexible capillary 

 setae. (Plate 65, fig. 1). 



