LEODICID^E OF THE WEST INDIAN REGION. 



115 



and later ones gradually become longer until about the thirty-fifth somite, but behind 

 this they are of practically uniform widths until near the posterior end. Beginning 

 with the first somite, becoming more noticeable in the region of the tenth, and dis- 

 appearing entirely by the forty-third somite are green spots in each somite. These 

 are arranged in a dorso-median, an admedian, and a lateral row, there being two spots in 

 each row, the anterior one usually the larger. There is a transverse row of narrow 

 lines in each somite, just anterior to the middle. In one Bermuda specimen, apparently 

 of this species, I was unable to see any of the transverse rows of spots described by 

 Verrill. 



In preserved material the color disappears, the most noticeable coloration being the 

 transverse brown band in each somite. This is true of Yen-ill's type as well as of material 

 from Key West and Bermuda. Figure 12, plate 

 9, was drawn from a Bermuda specimen, and 

 figure 13 from specimens taken at Long Key, in 

 the Dry Tortugas, in 1915. In neither case did 

 the artist represent the green pigment. The head 

 corresponds with the above description, but the 

 relative position of the two pairs of eyes seems to 

 vary. This is possibly dependent on the amount 

 of contraction. 



The parapodia (text-figure 425) are of uni- 

 form character throughout the body, varying 

 only in size. Each has a prominent post-setal 

 lobe and carries a very few setae. The setse are 

 also uniform in character throughout the body; 

 each (text-figure 426) has a short, moderately 

 strong shaft, which flattens and curves abruptly 

 and is then drawn out into a long, sharp point. 

 At the curve are thin wings (one only shown in 

 figure 426), which are noticeably striated and 

 which sometimes show, apparently as a result 

 of pressure, roughened or toothed edges. 



The maxilla (text-figure 427) has the two 

 long basal rods characteristic of the genus, with 

 ventrally a light-brown thickening of the chitin. 

 The forceps has on either half a thickened toothed 

 base and a slender, slightly curved terminal por- 

 tion. Each first paired plate has about 10 teeth, 

 in the second pair each has 5, in the third each has 

 4, in the last each has 1 very slender tooth. The 

 alternation of long and short teeth in these plates 

 shown in the figure seems to be a very character- 

 istic and constant feature. 



The mandible (text-figure 428) is rather heavy, with slender posterior shafts and 

 with the anterior edges rounded on the inner corners, but nearly square on the outer. 



A. maculosa was rare in my Tortugas collections, but common in Bermuda, occurring 

 with Lumbrinereis maculata in mud from a number of localities. Verrill's specimens 

 were collected at Flatts Inlet, Bermuda. 



TEXT-FIGURES 425 to 428. 

 Arabella maculosa Verrill. 



425. Middle parapodium x55. 



426. Seta x395. 



427. Maxilla x34. 



428. Mandible x34. 



