S20 S. ISHII. 



Measurements taken from 3 female specimens are as follows 



Spec. 



Body without tail. 



Length of tail. 



Legth. 



Width in the widest part 

 of mesosome. 



A 



5 mm. 



3,5 mm. 



3,5 mm. 



B 



7 » 





5 » 



C 



6 „ 



3,5 » 



4 „ 



Cephalon. The cephalon is small and of a roundish shape. In 

 specimen C, it is 0,8 mm. long and about as wide. It is deeply sunk 

 into the mesosome, and can be seen only from the dorsal side after 

 detachment from the host. Eyes are present in a pair in the anterior 

 part of the cephalon. They are feebly developed and usually not 

 clearly visible from the outside, being more or less concealed under 

 adjacent legs. There are two pairs of rudimentary antenna?. Measure- 

 ments of them taken from specimen C are as follows : 

 First or inner antenna; (3-jointed) : 



Basal joint, 0,140 mm. long, 0,140 mm. thick. 

 Middle ,, 0,048 mm. „ 0,040 mm. „ 

 Distal ,, 0,020 mm. ,, 0,028 mm. ,, 

 Second or outer antenna; (/-jointed) 15 : 



Basal joint 



2nd joint, 0,160 mm. long, 0,080 mm. thick. 



3rd 

 4th 

 5 th 

 6th 

 7th 



0,084 mm. 

 0,072 mm. 

 0,032 mm. 

 0,032 mm. 

 0,010 mm. 



0,060 mm. 

 0,042 mm. 

 0,024 mm. 

 0,016 mm. 

 0,008 mm. 



1) In one case, one of the second antennce was observed to be 5-jointcd. 



