TELAKE EPIPOLASIS. 347 



biannulate, the dividing annular surface ordinarily very distinct. The somites 

 increase in length to the region from the fortieth to the fiftieth somites. The 

 last somite of the anterior division (the thirty second) is four times wider than 

 long. As usual, the somites in the more posterior region are a little depressed 

 as compared with the anterior ones. 



The body is divided into two regions according to the character of the 

 parapodia, these being smaller and with much fewer setae from the thirty second 

 somite, inclusive forward, and larger and with longer and more nimierous setae 

 from that point caudad. The change takes place abniptly. The parapodia 

 of the anterior region are bifid distally, with slight neuropodial and notopodial 

 lobes which are equal and very similar. In comparison with the width of the 

 body the parapodia are veiy short and slender, thicker dorsoventrally than 

 anteroposteriorly. Each bears two long presetal lobes, or ligulae, one on each 

 branch, of which the notopodial is the longer. There are no distinct postsetal 

 Ups. The neurocirri are attached distad of the middle of the parapodia. Each 

 is broadly united with the neuropodium at its base and is conicaUy narrowed 

 distad, falling short of attaining the end of the neuropodium. The notocirri 

 are attached on the side of the somite, well above the base of the neuropodia. 

 Each is a small nodular body constricted at the attachment and shortly sub- 

 conically pointed distad. (Plate 63, fig. 4). The anterior pairs of parapodia 

 decrease in length decidedly cephalad, the first two or three pairs in particular 

 being much reduced. 



The parapodia of the posterior, or sexual, division of the body are similar 

 in general structure to those of the anterior, but are decidedly broader in the 

 dorsoventral direction, proportionately much more flattened in the cephalo- 

 caudal direction, and, as mentioned, have more niunerous and somewhat longer, 

 more widely spreading, setae. In a typical parapodium of this region, as for 

 example the thirty seventh, the depth at the base is great and decreases decidedly 

 distad. The hgulae are larger and more foUaceous, each broad at base and 

 narrowed to an acute tip, and extended as a narrow band some distance along 

 the dorsal edge of the notopodium, or the ventral of the neiu"opodivmi, as the case 

 may be. The two ligulae are subequal, or the nem-opodia may be somewhat 

 larger. On the dorsal side there is a tliin vertical membrane running as a narrow 

 convex band proximad to the base of the notopodium, and distad more narrowly 

 about the end caudad of the setae. Above this at the base is the notocirrus, 

 which is in the form of a very small rounded nodule. Along the ventral edge 

 of the neuropodium is attached the neurocLrrus. This is somewhat foUaceous 



