AGRICUIiTURAL EXPERIMpNT STATION. 139 



swellings which are broadest at the end and flat or sliglitly 

 rounded. These hairs curve in the same direction as the claw 

 and extend considerable distance beyond it. There is a free 

 joint between the seventh segment of the leg and the foot portion. 

 The two joints and the claw make up the moveable parts. When 

 walking on glass or any smooth surface the mite puts the paw out 

 behind as one would bend the hand backward at the wrist, resting 

 on the end of the seventh joint, the claw and the end of the four 

 stiff hairs, the terminations of which are put squarely down upon 

 the surface. These hairs with enlarged ends may be used for 

 spinning as suggested by Murray, but one cannot watch the 

 movements of this mite without believing they are adapted for 

 locomotion. 



According to Murray, the stiff hairs on the feet of Tetranychus 

 telareus (the red spider) are attached to the claws, and he has so 

 represented them in a cut (Economic Entomology, p. 97). In 

 this species they are appendages of the small joint of the foot 

 next to the claws. Also he says these hairs have globular termi- 

 nations and so figures them. In our specimens the hairs end in 

 trumpet-mouth like terminations, disc-like at the ends and are put 

 flat on the surface in locomotion. Prof. Riley in T. 6 — 

 maculatus, (U. S. Agrl. Report, 1889, p. Ill), represents the 

 hairs as originating from the back of the claws and as hooked at 

 the ends. The mouth-parts of the rec? spider as shown by Murray, 

 and those of T. 6 maculatus, Riley, differ from those of our 

 species. 



According to the characters laid down for the genus Tetranychus 

 by Murray, there should be only seven joints in the legs. We are 

 at a loss to know just what was included by him in the terminal or 

 tarsal joint. There are seven segments in the leg above the move- 

 able joint in the foot region spoken of above. If the three 

 moveable elements below this joint constitute a distinct segment, 

 then there are eight joints to the leg. If the fixed short segment 

 above the moveable joint is concluded in the terminal segment, 

 then there are only seven joints to the leg. The location of the 

 joint is shown in Fig. 3, a. Extending from the front of the 

 carapace are the mouth parts, made up of the palpi, rostrum or 

 beak, proboscis and mandibles. The palpi (see Fig. 4) are seven 

 jointed. The terminal joint is short, about .008 m. m., with paral. 

 lei sides and an obtuse rounded end, twice as long as broad. Second 

 joint is broadly conical, somewhat broader at the base than long, 

 length about .015 m. m. at top and .025 m. m. at base, bearing on 



