624 A. E. Verrill — Turbellaria^ Nemertina, and 



wider than long, and slightly trilobed anteriorly, eraarginate poste- 

 riorly. Eyes small, black, the anterior ones a little larger and farther 

 apart. Palpi large, divergent, the free pai't rather longer than head, 

 the inner margin concave, tips obtuse. Tentacle slender, tapered, 

 rather short, extending about to ends of palpi. Antennae tapered, 

 somewhat shorter and smaller, distinctly beaded, with 8 to 10 annuli. 

 Upper tentacular cirrus similar in form, about twice as long as ten- 

 tacle, with about 15 annuli ; lower one smaller, about \ as long, with 

 8-10 annuli. The first and some of the other dorsal cirri are as long- 

 as, or longer than, the dorsal tentacular cirri, and equal to about twice 

 the breadth of the first segment. In the type longer cirri occur on 

 segments ] , 2, 4, 6 ; shorter ones on 3, 5, 7, 8. Farther back the longer 

 dorsal cirri are mostly less than the diameter of the body, and on the 

 posterior half they ai'e equal to about \ the diameter of the corre- 

 sponding segments. They are all tapered and neatly beaded. Cau- 

 dal cirri larger than the adjacent dorsal cirri and twice as long. 



The anterior setae, 6-7 in a group, have the blade narroAV, nearly 

 straight, 3 to 3|- times as long as broad ; shorter below and on the 

 more posterior segments ; the tips minutely bidentate. Setie beyond 

 the 20th segment are reduced to 2 or 3 in each fascicle, much longer 

 and stouter than the anterior ones and about equal to the dorsal 

 cirri ; the longer one is a two-pronged crotchet ; on the compound 

 ones the blades are short, ratios 1 : l^-lf , the tips bidentate ; on the 

 last 10 segments the setae are all compound. They are accompanied 

 by 1 or 2 spiniform acicula. 



The oesophagus is brown, very long and slender, occupying about 

 13 segments ; its tooth is near the front margin, which is unevenly 

 finely serrulate with about 16 denticles. The stomach is narrow, 

 cylindrical, rather short, occupying about 5^ segments,* with many 

 crowded rows of small cell-groups and a median sulcus. Color, yel- 

 lowish white. Length, in formalin, about 15™"^ ; diameter, .5"™. 



Branchiosyllis lamellifera, sp. iiov. 



A small greenish syllid with compact segments, wide truncated 

 head, blunt falcate palpi, beaded dorsal cirri, and large parapodia, 

 having a leaf-like gill on their anterior side. Setae with short blades. 



Head large, broader than long, widest near the front; the anterior 

 margin nearly straight, but has a small rounded lobe in the middle ; 



* The number of segments occupied by the stomach or oesophagus varies con- 

 siderably in all the species, owing to the great contractility of the segments. It 

 is a character of some value, however, if taken relatively. 



