LEODICID.E OF THE WEST INDIAN REGION. 



55 



posteriorly from there. The animal appeared to be regenerating a posterior end, for 

 the last somite has a parapodium on one side and a very short pygidium with two short 

 anal cirri on the other. All dorsal cirri are colorless. 



The first parapodium (text-figure 174) has a long, cylindrical dorsal cirrus 

 and a large, bluntly oval ventral one. There is a small post-setal Up, and two aciculae 

 extend to the surface. The tenth (text-figure 175) has a much greater height than the 

 first, with a long, slender dorsal cirrus, the ventral one conical at the end of a swelling. 

 The setal lobe is rounded at the apex, with vertical anterior and rounded posterior lips 

 and two aciculse. A gill-bearing parapodium (text-figure 176) has very slender cirri 

 with the gills arising from a broad base just dorsal to the dorsal cirrus. The setal lobe 

 is pointed and the acicula extends into it. A ventral acicula protrudes to the surface 

 ventral to the setal lobe. There are needle aciculse in all dorsal cirri. 



The gills begin on the right side on somite 20 and on the left side of somite 21, the 

 former with two filaments and the latter with one. The filaments are long, those of 

 opposite sides being capable of meeting across the dorsal surface. The anterior gills 

 have usually only two filaments, but in the region of somite 100 another is added, and 

 three is the characteristic number throughout the remainder of the body. So far as 

 I could determine, they continued to the very end, though the posterior ones were 

 shriveled and difficult to see. 



The simple seta? (text-figure 177) are small, with an asymmetrical swelling toward 

 the end and no lateral wing. The compound ones (text-figure 178) have rather heavy 



TEXT-FIGURES 174 to 183. 



174. First parapodium x40. 



175. /Tenth parapodium x34. 



176. Gilled parapodium x34. 



177. Simple seta x50. 



Leodice bucciensis Treadwell. 



181. Ventral acicula x200. 



182. Maxilla x24. 



183. Mandible x24. 



178. Compound seta x80. 



179. Pectinate seta x3SO. 



180. Dorsal acicula x200. 



