appendages, one pointing directly backward and the other two extend- 

 ing out at a considerable angle. The entire surface of the body is 

 covered with very minute scales like those of a moth. Six legs 

 spring from the thorax, and, while not very long, they are powerful 

 and enable the insect to run with great rapidity. 



In certain peculiarities of structure, and also in their habits, these 

 anomalous insects much remind one of roaches, and their quick, 

 gliding movements and flattened bodies greatly heighten this resem- 

 blance. More striking than all, however, is the remarkable devel- 

 opment of the cox£B or basal joints of the legs in the silver fish, which 

 finds its counterpart in roaches, and, taken in connection with the 

 other features of resemblance, seems to point to a very close alliance 

 between the two groups, if, indeed, the silver fish are not merely 

 structurally degraded forms of roaches and to be properly classed 

 with the Blattidae. 



Another of the common silver fishes of this countrj^, referred to in 

 the opening paragraph, has developed a novel habit of frec^uenting 

 ovens and fireplaces, and seemingly revels in an amount of heat 

 which would be fatal to most other insects. It disports itself in 

 numbers about the openings of ranges and over the hot bricks and 

 metal, manifesting a most surprising immunity from the effects of 

 high temperature. This heat-loving or bakehouse species (fig. 33) 

 was described in 1873 as Lepisma domestica by Packard, who 

 reported it to be common about fireplaces at Salem, Mass. This 

 species is also very abundant in Washington. What is evidently 

 this same insect has become very common, particularly in the last 

 year or two, in England and on the Continent, where it manifests 

 the same liking for hot places exhibited by it in this country. The 

 habit of this species of congregating in bakehouses and dwellings, 

 about fireplaces and ovens, has given rise to the common appellation 

 for it in England of "fire-brat." Similar descriptive names are 

 applied to it also on the Continent. This species closely resembles 

 the common silver fish in size and general appearance, but may be 

 readil}^ distinguished from it by the presence on the upper surface 

 of dusky markings. It also possesses well-marked structural differ- 

 ences, which have led to its late reference to a distinct genus — 

 Thermobia. An Italian entomologist, Rovelli, has described this 

 insect under the descriptive name furnorum, from its inhabiting 

 ovens, and the name of the genus to which it is now assigned by 

 English entomologists is also descriptive of its heat-loving chai'acter. 

 A Dutch entomologist, Oudemans, reports that he has found it in 

 abundance in all bakehouses that he has examined in Amsterdam, 

 where it is well known to bakers and has received a number of 

 familiar names. 



