LEODICID.E OF THE WEST INDIAN REGION. 67 



In the Tortugas specimens the peristomium was brown (plate 5, figure 10) and 

 densely covered with pearly white spots, not all of which are shown in the figure. The 

 next three somites had each a pearly white spot in the mid-dorsal line, their dorso- 

 lateral surfaces colored like the prostomium, but with fewer white spots. These median 

 white areas appear more or less irregularly in later somites as far as the eleventh, and 

 occur in every somite behind this to about the twenty-fifth, behind which the brownish 

 color disappears, though the white spots continue. The middle and posterior regions 

 often have a decidedly bluish tint (plate 5, figures 9 and 11). 



Usually somites 10 and 11 are entirely white, but in one specimen from Porto Rico 

 (plate 5, figure 9) this white color extends over somite 12 and is less marked on 10. 

 At about the region of somite 50 the color largely disappears, leaving only a pearly 

 luster to the skin and a mottling with white spots. The Tortugas specimens were less 

 pigmented than were those from Porto Rico, as is indicated by a comparison of figures 

 9 and 10. In the Porto Rico specimens (plate 5, figure 9), there was on the ventral 

 surface of about the last 40 somites a transverse brown band, which did not appear 

 on individuals from other localities. The absolute size varies with the degree of expan- 

 sion. One with a peristomium width of 3.5 mm. showed a slight narrowing in the fol- 

 lowing somites, but a later increase in width to 7 mm. at about somite 40. The anterior 

 region, back to about somite 40, is noticeably convex on the dorsal surface, but behind 

 this region the body is much flattened. The length may be as much as 150 mm., with 

 about 200 somites. They are very easily broken in handling, and, from the fact that 

 many are regenerating posterior ends when collected, it would seem as if they are fre- 

 quently broken under their normal life conditions. 



The prostomium (plate 5, figure 10) is bilobed, with a rather broad depression 

 between the lobes. The tentacles extend to only a short distance beyond the prostomium, 

 are approximately equal in size, and are irregularly banded with brown. The peristo- 

 mium may be considerably longer than broad, or it may be so contracted, as in my 

 original description (loc, cit., fig. 1), as to have the transverse diameter much the greater. 

 The later somites are quite similar in size, but behind somite 9 they become shorter. 



The first parapodium (text-figure 224) has a narrow basal part, but abruptly widens 

 just beyond this. The setal portion has a conical post-setal lip but no definite anterior 

 one. The dorsal cirrus is large, sagittate in outline, while the ventral cirrus is much 

 heavier and is attached to the parapodium for the greater part of its width. There is 

 a single large acicula, but no needle aciculse extend into the dorsal cirrus. 



The ventral cirrus of the third parapodium (not somite, as stated in my original 

 description, p. 3) shows a prominent, swollen basal portion, which reappears on later 

 somites as far as somite 25, but behind this point it gradually disappears. The dorsal 

 cirri, which anteriorly are prominent, become small later and in most of the body are 

 very inconspicuous. (Compare text-figures 224 and 225.) 



The tenth parapodium (text-figure 226) has a prominent post-setal lobe, rounded 

 at the apex and bent slightly dorsally, the end of the setal lobe itself being bent ventrally. 

 The dorsal cirrus has an asymmetrical sagittate outline, and is relatively much smaller 

 than in the first parapodium. The ventral cirrus is small, arising from the end of a 

 swollen, cushion-like base. 



In later somites the post-setal lobe becomes smaller and, as shown in text-figure 

 225 (of the thirty-fifth parapodium), it is merely a pointed lobe extending only a short 

 distance beyond the anterior lip. The dorsal and ventral cirri are smaller than ante- 

 riorly, but retain practically their earlier form. In parapodia from farther posteriorly 

 (text-figure 227), both cirri are small, the ventral one loses its swollen base, and the 

 conical post-setal lip again makes its appearance. There are two short, colorless anal 

 cirri (plate 5, figure 12). 



