38 THE COCCIDAE 



among the generalized subfamilies, particularly the Monophlebinae, 

 than from the specialized subfamilies. Eight pairs are recorded as 

 present in species of Stigmacoccus, seven in Perissopneumon, 

 Monophlebus, and Droschia, and two or three in Icerya on segments 

 six to eight or seven to eight. Abdominal spiracles are also re- 

 ported as present in Cryptokermes, Margarodes, and on the first 

 segment of Conchaspis. All the species of Orthezia examined have 

 seven pairs and there are eight pairs in all the American species 

 of Xylococcus. Abdominal spiracles are also present in certain 

 species of Steingelia, Stomatacoccus, Coelostomidea, and Kuwania. 

 Cavaerae are rarely if ever associated with the abdominal spiracles. 



Anal Ring. The anus in certain genera is surrounded by an 

 elevated ring-like structure, known as the anal ring. It was 

 formerly known as the genital ring or genito-anal ring from the 

 mistaken notion that it surrounded the vulva. The anal ring 

 generally bears a number of setae, typically six, which are longer 

 and stouter than the other setae of the body. There are cerores 

 which vary in form and position in the different genera and species 

 which are arranged irregularly or in rows between the setae. 

 The wax excreted by the anal ring is generally different in 

 character from that excreted by the cerores on other parts of the 

 body and frequently forms a tube through which the honey-dew or 

 excrement is passed. The prominent anal wax-tube formed by 

 species of Xylococcus is not excreted in this way but by anacerores. 

 The anal ring is usually wanting in the adults of the Keraiesiinae 

 but present in a rudimentary condition in the nymphs. 



Anal Ring Setae. The setae borne by the anal ring are known 

 as the anal ring spines, the anal ring hairs, or the anal ring setae. 

 They are usually six in number. There may be as few as two and 

 as many as eight, ten, twelve, or even thirty. Newstead reported 

 twenty to twenty-four in Aclerda, but Green does not consider 

 these as anal ring setae. Some authors have recorded a large 

 number of anal ring setae as present in certain genera of 

 Lecaniinae, but these are according to Green longitudinal corruga- 

 tions of the eversible sac of the rectum, the anal tube. 



Anal Lobes. Most coccids with an anal ring are also provided 

 with anal lobes. These are the shoulder-like projections or lobes 

 located at the caudal end of the abdomen on each side of the anal 

 ring. They may be present in the nymphal stages and wanting in 

 the adult, in fact they are usually larger and more prominent in 

 the nymphal stages. They vary greatly in form and size. In some 

 species they are so large that the caudal end of the abdomen 



