196 PROCEEDINGS OF THE ACADEMY OF [^I^Y, 



Parapoclia of branchiate segments II to V large and conspicuous 

 (figs. 2 and 3) ; both notopodia and neuropodia provided with large, 

 foliaceous, postsetal laminae, usually overlapping or at least touching 

 across the sinus; the former rising as a long dorsal process external to 

 but quite free from the gill; the latter nearly circular, and in the case of 

 the first one (II) apparently ^bearing a slender cirrus-like process on the 

 ventral border. Behind V the parapodia are much smaller and soon 

 become reduced to the form shown in fig. 4, in which the notopodial 

 and neuropodial postsetal lamellse have a similar form, but the former 

 is twice the size of the latter. Posteriorly they become still smaller. 



Branchiae 5 pairs, on somites II to VI inclusive. All large, exceeding 

 the diameter of the body even in contraction, erect, and arising from 

 the dorsum close to the notopodia. The first pair (fig. 2) have a central 

 stem containing a large vascular loop and ending in a slender, free 

 filament. The basal f of the stem is crowded, chiefly on the posterior 

 and medial surface, with numerous slender, finger-like processes, each 

 with a small vascular loop connected with the two limbs of the stem 

 loop; free surfaces ciliated. The last pair are similar, but the papillae 

 are longer toward the base and distributed on all sides of the proximal 

 f of the stem (fig. 5) . The 2d and 3d (fig. 3) are simply flattened and 

 ligulate, marked across the posterior face by numerous very fine 

 transverse ridges which correspond with delicate branches uniting the 

 two sides of the vascular loop. The 4th is intermediate, resembling 

 the last in form, but bearing a few filaments along its inner and posterior 

 margin. 



Anterior parapodia bear capillary setae exclusivelj^, arranged in 

 shaggy, fan-shaped, vertical tufts in both rami, and curving outward 

 and upward, the dorsal members of bundles on the branchial notopodia 

 being especially long, and those of the first two exceeding the width 

 of their respective somites. They are all simple, with very narrow 

 wings or none, and very acute. Behind the branchial region the 

 notopodials become gradually, and the neuropodials quickly, smaller 

 and fewer. At about XL 1 or 2 crochets appear in the notopodium 

 along with several very long, thread-like, flexible setae. Little further 

 change occurs within the length of the specimen. In the neuropo- 

 dium crochets appear at XV ; at XXV there are C or 7 crochets alter- 

 nating with as many very small, straight, delicate setae; at L there are 

 about 10 crochets and a few still smaller setae. Crochets (fig. 6) color- 

 less, slender, terminated by 1 large and 3 or 4 small teeth, all enclosed 

 in a spacious hood of two halves. 



Body walls generally colorless and translucent, allowing the red 



