LEODICID^ OF THE WEST INDIAN REGION. 37 



its posterior edge. The antennse are marked with brown bands, much as in L. longicirrata, 

 and the white patches make it resemble L. rubra. In life the color is diagnostic, but 

 in alcoholic material the three species might be confused. L. binominata may be dis- 

 tinguished from rubra by the possession of longer tentacles and fewer gills and from 

 longicirrata by the presence of the white patches. 



The length of my Tortugas specimens was 50 mm., while one collected in Bermuda 

 measured 80 mm. after preservation. 



The median tentacle (plate 3, figure 10) may extend to as far as the fifteenth somite. 

 It has as many as 26 articulations and is moniliform at the apex. The inner paired are 

 about three-quarters of the length of the median, the outer paired not more than half 

 as long as the inner, and they are all articulated. The nuchal cirri extend to the anterior 

 margin of the peristomium, are articulated, and in life are banded with flake-white 

 and brown. The other cirri throughout the body are relatively large, and there is a 

 single pair of anal cirri, which are banded with brown, but (as may be seen on preserved 

 material) are only obscurely articulated (plate 3, figure 12). 



The prostomium is described above. The peristomium (plate 3, figure 10) is wider 

 than the prostomium and about twice as long as somite 2. Later somites increase in 

 width to about the middle of the body, and thence there is a gradual decrease to the 

 posterior end. 



The gills are restricted to the anterior end of the body, lying (in all the specimens 

 I have examined) between somites 7 and 35. Beginning with 1 or 2 filaments on somite 

 7, the number increases rapidly (plate 3, figure 11) and with some regularity to as many 

 as 12 on somite 14. One individual showed 12 as the maximum number on somites 14 

 and 26, while somite 18 had only 9. Another had 13 filaments on somite 18. The last 

 gills are on somites 33 to 36. The filaments are always rather heavy, but are always 

 more slender than the dorsal cirrus (text-figure 95). 



The first parapodium (text-figure 96) has a setal portion with a rounded posterior 

 lip and two rather long aciculse toward its dorsal surface. The dorsal cirrus shows an 

 articulation near the end, and a tuft of needle aciculae extends into its base. The ventral 

 cirrus in the specimen figured had been flattened by the pressure of the cover-glass and 

 is really more globular toward the ba.se than is represented, approaching in this respect 

 the condition in the eleventh. The eleventh parapodium (text-figure 95) has a rounded 

 post-setal lobe with two rather heavy aciculae toward its dorsal surface. The dorsal 

 cirrus has a single articulation near its middle and a constriction near the apex, this 

 latter not being a true articulation. There is an obscure pigment spot near its base 

 and a tuft of needle aciculse extends into it. The ventral cirrus has a globular base, 

 its terminal portion being rather slender. 



A parapodium from the middle of the body behind the gills (text-figure 97) has two 

 dorsal aciculse protruding between the setal lobes and a ventral one just dorsal to the 

 ventral cirrus. The dorsal cirrus is slender and not articulated, while the ventral one 

 retains a trace of its globular base, but is otherwise slender. Pigment spots are scattered 

 over the surface of the entire parapodium and needle aciculse occur in the dorsal cirrus. 

 Toward the posterior end of the body the parapodia have essentially the same structure 

 as in the last, but the dorsal cirri are absolutely as well as relatively longer than in those 

 farther forward, so that they are more prominent in the posterior regions. 



The simple setae (text-figure 98) are long and slender, only slightly curved, and with 

 minute denticulations along their expanded portion. The compound setae (text-figure 



99) have large basal joints, the terminal joints small. The latter have equal apical and 

 subapical teeth and a smooth hood. The apex of the basal joint is rounded and tooth- 

 like, and there are minute denticulations proximal to it. The pectinate setae (text-figure 



100) have a few (about 8) rather large teeth. 



