NO. 1382. 



THE ACARINA OR MITES— BANKS. 



01 



middle, the penultimate joint ending- in one or two claws, the last joint 

 (often clavate) appearino- as an appendage or '•' thund)" to the preceding 

 joint. The legs are seven-jointed; the tarsi terminate in two small claws. 

 The legs are clothed in the same manner as the Ijody. There are two 

 ej'es upon each side of the cephalothorax, quite frequently l)orne on a 

 distinct pedicel. Along the median line 

 of the cephalothorax there is commonly a 

 crista or dorsal groove similar to that of 

 the lihyncholophidw. This crista is en- 

 larged at the middle or postei'ior end into a 

 triangular area, called the areola, in which 

 are two pores from which arise bristles. "»\ 



Doctor Oudemans terms these pseudo- ^''" ''-^^^ "^ teombidium. 

 stigmata and pseudostigmatic organs. The latter are sometimes cla- 

 vate at or near tip. There is no proof that these are homologous with 

 the organs of the same name in the Oribatida?, although it is possible. 



Sometimes these organs are present, although 

 the crista is absent, and in one species there 

 are two pairs of the organs. The function 

 of these organs is entirely unknown. The 

 genital aperture is situate between the hind 

 cox}\?; the anal opening is smaller than the 

 genital and placed a little behind it. 



The larvie are six-legged mites and para- 

 The}", with other larval forms, w^re formerly 



Fig. 4-5.— Claws of Trombidium. 



Fig. 4t'i. — Leg I of trombidium. 



sitic on various insects, 

 supposed to be adult and to constitute a distinct famih^ under* the name 

 of Microphthiridte. Three of the genera of that family, Leptns^ 

 'Ocyjxtiix^ •Andi.Atoina {or Adoma)^ are 

 now known to l)e larval Trombidiids. 

 Some of these larv* are, in certain 

 localities, very numerous, and will 

 attach themselves to man, causing in- 

 tense itching, soreness, and even more serious complications. They 

 have received the popular name of " red bug." In parts of the South- 

 ern States the *' red bug " is often a source of great annoyance. They 



burrow l^eneath the skin and produce 

 inflamed spots. It is an unnatural situ- 

 ation for the mites, and they soon die, 

 but the waiting is not pleasant. They 

 can be killed by anointing the affected 

 spots with an ointment or salve con- 

 taining sulphur. Some recommend 

 sponging with a weak solution of car- 

 bolic acid (an ounce to a quart of water) after a soap bath. Allied spe- 

 cies occur in most warm countries. In France, where they are often 

 k^ery troublesome, they are called "rouget" or "aoutat,'' and are the 



Fig. 47.— Mandible of Trombidium. ;>, 

 tracheal pores; t, trachea. 



