NEW MALLOPHAGA. I 25 



gins short and hardly distinct from lateral margins; lateral 

 margins narrowly darker colored than rest of segment; 

 no hairs. Metathorax almost three times as long as pro- 

 thorax; sides subparallel; hind margin feebly convex or 

 slightly angulated on abdomen; with four long hairs and 

 one short one in posterior angles, the short hair being 

 next to the outermost hair; the lateral margins very nar- 

 rowlv darker edged along their hinder half. Legs con- 

 colorous with body, dorsally narrowly darker edged. 



'Abdomen slender elongate, subparallel-sided, growing 

 slightly wider to segment 7, segments 8-10 tapering; seg- 

 ments 1—7 subequal in length, segment 8 half as long as 

 segment 7, segment 9 shorter than segment 8; segment 

 10 obtusely two-pointed; very sparsely haired, segments 

 2—6 with one short hair on margin just in front of poste- 

 rior angle; a square pale brown blotch on each side of 

 segments 1-7, darker-edged outwardly, and separated by 

 a distinct median uncolored line; blotches of segment 8 

 meeting, and the markings of segment 9 continuous. 



Lipeurus constrictus n. sp. (Plate viii, tigs. 7 and 8.) 



Found on three out of six specimens of the Surf 

 Scoter, Oidemia fierspiciUata, and on one out of six speci- 

 mens of the White-winged Scoter, Oidemia deglandi 

 (Bay of Monterey, California) ; also found on a speci- 

 men of -perspicillata taken at Lawrence, Kansas (Kansas 

 River, during migration). The new form belongs to the 

 group bisetosi, and is distinguished from sqitalidus, the 

 member of the group which the new form most resembles 

 by the smaller size, by the narrow basal abdominal seg- 

 ments, and by the concave hinder margin of the clypeal 

 signature. Many specimens, males, females and young 

 were taken. 



Description of the male. Body, length, 2.31 mm., 

 width 5 mm.; general habitus of squaltdus, but distinctly 



