26 



THE COCKROACH : 



Female. 



Antenna shorter than the body, 

 the third joint longer than 

 the second. 



Wings and wing-covers rudi- 

 mentary. 



Mesosternum divided. 

 Abdomen broader. 



Terga 8 and 9 not externally 

 visible. 



The 10th tergum notched. 



The 7th sternum divided be- 

 hind. 



The external outlet of the 

 rectum and vulva between 

 the 10th tergum and the 

 7th sternum. 



No sub- anal stvles. 



Male. 



Antenna rather longer than 

 the body, the third joint 

 about as long as the second. 



Wings and wing-covers well 

 developed. 



Mesosternum entire. 

 Abdomen narrower. 

 Terga 8 and 9 externally visible. 



tergum 



hardly 



The 10th 

 notched. 



The 7th sternum undivided. 



The outlet between the 10th 

 tergum and the 9th sternum. 



Sub-anal styles. 



Parasites. 



We have before us a long list of parasites* which infest the 

 Cockroach. There is a conferva, an amoeba, several infusoria, 

 nematoid worms (one of which migrates to and fro between the 

 rat and the Cockroach), a mite, as well as hymen opterous and 

 coleopterous Insects. The Cockroach has a still longer array of 

 foes, which includes monkeys, hedgehogs, pole-cats, cats, rats, 

 birds, chamseleons, frogs, and wasps, but no single friend, unless 

 those are reckoned as friends which are the foes of its foes. 



Names in common use. 



A few lines must be added upon the popular and scientific 

 names of this insect. Etymologists have found it hard to 

 explain the common English name, which seems to be related to 



* See Appendix. 



