100 SANITARY ENTOMOLOGY 



based only on a recording liygrothermograph, checked by the above 

 mentioned instruments. 



The great bulk of work naturally is upon the reactions which take 

 place in the zone of activity. 



It must not be forgotten, however, that control work depends often 

 upon a correct knowledge of the lower zone of fatal temperatures, and 

 that successful storage of breeding material, until the investigator is 

 ready to use it, depends often upon a knowledge of the requirements of 

 rhiganesthesia. 



Following the awakening, the body takes up all its natural functions 

 and we must assume that sustenance is available. The first activities, 

 at temperatures just above the zero of activity, are naturally very 

 sluggish and this state of sluggisliness may be kno^\^l as RHIGO- 

 NOCHELIA, or sluggishness caused by cold. 



Some creatures are very sensitive to cold, usuall}' when the humidity 

 is high. Pain produced by the application of cold is called CRYAL- 

 GESIA. An abnormal sensitiveness to cold is known as CRYESTHESIA, 

 and a morbid sensitiveness as HYPERCRYALGESIA. These sensa- 

 tions are probably only experienced with a descent of temperatures. 



In the zone of effective temperatures or thermopractic zone there 

 is a point or a small restricted zone of temperatures at which all activi- 

 ties are most effective, that is, the greatest amount of work is accom- 

 plished with the least amount of exertion and the least loss of energy. 

 This is the so-called OPTIMUM, or perhaps better, PRACTICOTATUM, 

 meaning most effective. As temperatures ascend to the practicotatum 

 any given function is performed in proportionately shorter time. As. 

 the temperatures ascend above the practicotatum a particular function 

 may be exercised more rapidly but less accurately or less effectively, as 

 for instance, more eggs may be laid but fewer hatch : but the activity is 

 feverish and soon exhaustion takes place, or the individual gradually 

 becomes more stupid and sluggish. This heat sluggishness is therefore 

 called THERMONOCHELIA. 



Different reactions to heat may be experienced and these have all 

 received appropriate designations. As for example, a stifling sensation 

 is called THERMOPNIGIA ; an unusual sensibility to heat THERMAL- 

 GESIA, and a more intense sensibility HYPERTHERMALGESIA. The 

 ability to recognize changes of temperature is THER^IESTHESIA, 

 and its extreme is designated as THERMOHYPERESTHESIA, an 

 abnormal sensitiveness to heat stimuli. A fondness for heat or requiring 

 great heat for growth is called THER^NIOPJ' .1.IC, while resistance to 

 heat is called THERMOPHYLIC. When a stifimg temperature is ex- 

 perienced rapid breathing or THERMOPOLYPNEA is often experi- 

 enced. Contraction under the action of heat is designated as THER- 



