66 LEODICID^ OF THE WEST INDIAN REGION. 



cirrus is very small and does not extend to the end of the setal lobe. The ventral cirrus 

 has a broad base and a small, cylindrical terminal portion. The gills arise from rather a 

 broad base. There are two dorsal aciculae which have straight colorless ends, but are 

 darker toward their bases (text-figure 215), and a more slender single ventral form (text- 

 figure 216), with a bifid end covered by a hood, emerging to the surface just dorsal to 

 the ventral cirrus. Behind the gill-bearing somites (text-figure 217) the dorsal and ven- 

 tral cirri become more prominent, the former more slender than the latter. The anterior 

 and posterior lips are of equal length, while the setal portion shows two rounded lobes as 

 in more anterior somites. My original notes state that needle aciculse extend into the 

 dorsal cirrus, but I have not been able to demonstrate them in my preserved material. 

 Either there is variability in this respect or my notes were incorrect. 



The simple setae (text-figure 218) are slender, swollen slightly toward the apex, and 

 with entire edges. The compound sets (text-figure 219) have marked serrations on the 

 end of the basal portions, the terminal joints gently curved to acute apices, without 

 teeth. The pectinate setae of anterior somites (text-figure 220) have about 20 very fine 

 teeth, the terminal ones being a little longer than the others. Toward the middle of the 

 body a form with fewer and more prominent teeth makes its appearance, and posteriorly 

 these are the only ones represented. An extreme form is shown in text-figure 221. This 

 whole seta is much flatter than the ordinary kind, and has only 8 teeth. Intermediate 

 forms occur between these two kinds. 



The maxilla is very dark in color (text-figure 222). The carrier is rather small, the 

 terminal halves of the forceps large relative to their base, curved through about 20°. 

 The proximal paired plates have 6 teeth on the right and 5 on the left. The distal paired 

 plates have 7 on the right and 4 on the left; the unpaired has 8. The mandible (text- 

 figure 223) has slender dark shafts, the beveled portion is small, its surface covered with 

 a white incrustation. 



Collected in July 1915 at Mangrove Key in Key West Harbor, at Boca Grande, and 

 in Marquesas Key, within digging distance of low-water mark, in sandy mud. 



The type is in the American Museum of Natural History. 



Marphysa regalis Verrill. 



(Plate 5, figures 9 to 12; text-figures 224 to 234.) 



Marphysa regalis Verrill, 1900, p. 636. 



Marphysa fragilis Treadwell, 1911, pp. 2-5, figures 1-7. 



Verrill's description, published without figures, gave a very brief account of the 

 coloration, so that I did not recognize it when it appeared in my Tortugas collections, 

 and described it as a new species. Two lots were collected in the Tortugas, both in 

 soft coquina stone, one on either side of Loggerhead Key. A few were found in similar 

 stone in Condado Bay, near San Juan, Porto Rico, in 1915, and one was taken by the 

 American Museum party of that year 1.5 miles south of Cano Gorda Island, near Guanica 

 Harbor, on the southern shore of Porto Rico. It was very abundant in my 1916 collec- 

 tions in Bermuda, occurring everywhere in soft rock, and a few were collected in Mon- 

 tego Bay, Jamaica. 



There is a considerable amount of variation in the coloration of living specimens, 

 though their general appearance is unmistakable. The anterior and ventral surfaces of 

 the prostomium are white, while its dorsal surface, as far as the bases of the tentacles, 

 is brown, with more or less white between the bases of the tentacles (plate 5, figure 10). 

 There is a brown ring around the base of the unpaired and each inner paired tentacle. 

 The eyes are small, of a deep purple color. The tentacles are mostly uncolored and have 

 irregularly arranged brownish rings, but are not, so far as I can see, actually articulated, 

 though Verrill described them as such. 



