86 THE COCCIDAE 



c. Antennae of adult female consisting of ten or eleven segments; 

 second nymphal female with rudimentary legs; adult female 

 with well developed legs; rostrum of nymphs consisting of two 



or three segments. Coelostomidia Ckll. 



cc. Antennae of adult female consisting of five or six segments; 

 second nymphal female and adult female without legs; rostrum 

 of nymphs consisting of three segments. --Ultracoelostoma Ckll. 

 bb. Antennae of adult female wanting or represented by mere tu- 

 bercles; legs greatly reduced, represented by small tubercles with 

 large serrated claws; abdomen with seven pairs of spiracles; 

 antennae of second nymphal female short six-segmented tubercles, 

 legs tuberculate with minute claws; rostrum of nymphal females 

 consisting of two segments. Cryptokermcs Hemp. 



Xylococcus Loew. Four American species of Xylococcus have 

 been described. These can be separated by the following table based 

 upon that of Florence. Two species only are recognized by Ferris. The 

 species on alnus is considered the same as the species on birch which 

 is also recorded from beech. He records betulae Pergande from Ontario, 

 Canada, New York, and Michigan. 



SPECIES OF XYLOCOCCUS 



a. Abdomen of first nymph with caudal portion of ventral aspect with 

 single mesal pore; rectal tube of apodous nymphal stages of female 



with single ring of anacerores. California on Cupressus 



macrocarpae Coleman. 



aa. Abdomen of first nymph with caudal portion of ventral aspect with 



more than one mesal pore; rectal tube of apodous nymphal stages of 



female with two groups of anacerores, cephalic and caudal group. 



b. Rectal tube of apodous nymphal stages of female with only single 



ring of anacerores in caudal group; abdomen in first nymphal 



stage with caudal portion of ventral aspect with mesal row of 



five pores. Lake Superior Region on Betula bstulae Pergande. 



bb. Rectal tube of apodous nymphal stages of female with more than 

 one ring of anacerores in caudal group. 



c. Rectal tube of apodous nymphal stages of female with two 



rings of anacerores in caudal group; abdomen in first nymphal 



stage with caudal portion of ventral aspect with mesal row of 



two to four pores. California on Quercus. .-quercus Ehrhorn. 



cc. Rectal tube of apodous nymphal stages of female with three 



rings of anacerores in caudal group; abdomen in first nymphal 



stage with caudal portion of ventral aspect with mesal row of 



six or seven pores. California on Alnus alni Florence. 



Coelostoniidea Ckll. This genus contains four species, all from 

 New Zealand: compresses Mask, on Podocarpus; pilosa Mask, on Podo- 

 carpus and Fagus; wairoensis Mask, on Phormium and Leptospermum; 

 and zealandica Mask, on Muhlenbeckia and Rhipogonum. The species of 

 this genus have a similar structure of the rectum and execrete a tube of 

 wax like the species of Xylococcus. 



