230 0. POL1MANTI 



questi autori, perchè forse i metodi di ricerca da lui ado- 

 perati non erano buoni e l'animale in esperiménto veniva 

 sicuramente svegliato. 



Pembrey , dunque, studiando il tipo della respirazione 

 fece queste osservazioni sopra i ricci o i pipistrelli , sia 

 nello stato di letargo, sia nello stato di risveglio o di 

 veglia completa. Queste sono le importantissime conclu- 

 sioni alle quali giungono Pembrey e Pitts : 



« Gonclusions. There is a relation between the internai 

 temperature and the nature of the respiratory movements 

 of hibernating dormice , hedgehogs , marmots and bats. 

 Four distinct types of respiration may be described : 



(1) In the torpid animai with a temperature below 

 12° there are long periods of apnoea lasting several mi- 

 nutes and broken only by a few respirations. 



(2) In the inactive animai with its temperature rising 

 above 13° the periods of apnoea become shorter and the 

 respiration of Biots type with a sudden commencement 

 and cessation of breathing, or of the Cheyne-Stokes , type 

 with a graduai waxing and waning. 



(3) The animai is heginning to awake and its tempera 

 ture is about 16°, the periods of apnoea are very short 

 and infrequent ; the respiration becomes continuous. 



(4) The animai is awake : the respiration is continuous, 

 very rapid and accompanied by slight tremors or marked 

 shivering. The rectal temperature is rising rapidl'y and 

 is above 20°. 



The above stages refer especially to the dormeuse. In 

 the hedghog there are in stage (4) a short series of rapid 

 respirations ofter followed by a single deep sighing re- 

 spiration. This is also observed in the marmot. 



These types of respiration are observed in animals upon 

 wich no operation has been performéd. The animai was 

 awaking naturally or had been distitrbed by the obser- 

 vation of its rectal temperature. 



Cheyne-Stokes' respiration and the modification de- 

 scribed by Biot are normal in some of the stages of hi- 

 hernation. The former type is generally seen when the 

 dormouse is h-ss torpid and with a higher temperature 

 than in tliose cases when the lattei' type obtaìns. The 

 latter, bowewer, may graduali)- pass into the former. 



