428 OBSERVATIONS ON 



kitchen hearth swarms with young crickets, and young blattae 

 molendinariae of all sizes, from the most minute growth 

 to their full proportions. They seem to live in a friendly 

 manner together, and not to prey the one on the other. 



August 1792. After the destruction of many thousands 

 of blattae molendinariae, we find that at intervals a fresh de- 

 tachment of old ones arrives, and particularly during this hot 

 season : for the windows being left open in the evenings, 

 the males come flying in at the casements from the neigh- 

 bouring houses, which swarm with them. How the females, 

 that seem to have no perfect wings that they can use, can 

 contrive to get from house to house, does not so readily 

 appear. These, like many insects, when they find their 

 present abodes over-stocked, have powers of migrating to 

 fresh quarters. Since the blattae have been so much kept 

 under, the crickets have greatly increased in number. 



GRYLLUS DOMEST. HOUSE CRICKET 



November. After the servants are gone to bed, the 

 kitchen hearth swarms with minute crickets not so large 

 as fleas, which must have been lately hatched. So that 

 these domestic insects, cherished by the influence of a 

 constant large fire, regard not the season of the year, 

 but produce their young at a time when their congeners 

 are either dead, or laid up for the winter, to pass away the 

 uncomfortable months in the profoundest slumbers, and a 

 state of torpidity. 



When house-crickets are out, and running about in 

 a room in the night, if surprised by a candle, they give 

 two or three shrill notes, as it were for a signal to 

 their fellows, that they may escape to their crannies and 

 lurking holes, to avoid danger. 



CIMEX LINEARIS 



August 12, 1775. Cimices linear es are now in high 

 copulation on ponds and pools. The females, who vastly 



