124 THE CANADIAN ENTOMOLOGIST. 



Cephalothorax as broad as long ; beak three-fourths as long as leg i ; 

 each mandible bears dorsally two rather prominent bristles, a large bristle 

 situated at about one-third the distance from the anterior to the posterior 

 end of the mandible, and a similar bristle at about an equal distance from 

 the base of the same. Palpi surpassing the mandibles ; second segment 

 almost equal to the mandibles in length j third and fourth segments sub- 

 equal in length, but the third slightly stouter than the fourth ; distal 

 segment equal to the fourth in length, but about twice as broad at the 

 distal end as at the proximal end. Second segment with three or four 

 moderate bristles ; third with a single bristle ; fourth with two subequal 

 bristles on the outer margin, each about as long as the width of the 

 segment itself; distal segment with six bristles, two very large tactile ones 

 at the end of the segment, the outer about as long as the palpus itself, the 

 inner about three fourths as long ; between the two large tactile bristles 

 are situated two small bristles, the outer about as long as the segment 

 itself, the inner about two-thirds as long ; one situated laterally, about as 

 long as the segment itself, one situated dorsally near the base. A single 

 pair of eyes is present at the posterolateral border of cephalothorax. 



Abdomen about three-fifths as broad as long, broadest at the anterior 

 end ; two rather prominent, straight, posterior bristles situated on the 

 posterior margin near the median plane ; a pair of small shoulder bristles 

 also present. 



Legs large ; posterior pair longest ; anterior pair about one and one- 

 half times as long as the beak, and each succeeding pair slightly longer 

 than the pair preceding it Claws and caroncle of legs small. Tarsus of 

 leg 1 longer than tibia. 



Length, 0.70 mm.; breadth, 0.52 mm. 



Under bark of cottonwood. Collected by the writer at Urbana, 111. 



Bdella muscorum, n. sp. (Platevi, figs 4, 5, 6). — Red, body somewhat 

 darker than the legs and palpi. 



Cephalothorax large, lateral margins convex. Beak about as long as 

 the cephalothorax. Mandibles each with a prominent curved bristle near 

 the middle of the dorsal surface, and a smaller bristle near the base. 

 Palpi slightly surpassing the beak ; second segment fully two-thirds as long 

 as the mandibles ; third segment shorter but stouter than the fourth; distal 

 segment about one-half as long as segment two, but stouter, being enlarged 

 at its distal end. Segment two of palpus bearing a short bristle on its 



