— 64 — 



II. — Mardi. 1907 : Marked increase of température as 

 comparée! with February 1007; highesl March-temperatures for 



period of observation. 



m. _ July, 1901 : No marked rise of température as com- 

 pared with .Tune 1907; lowest July-temperatures for period of 

 observation. 



IV. — January, 1908 : Lowest températures of winter of 

 1907-1908; sudden drop of température as compared with 

 December 10t>7; lowest January- températures for period of 

 observation. 



V. — February, 1909 : Lowest températures of winter of 

 1908-1909 ; no appréciable fall of température as compared with 

 January 1909; lowest February- températures for period of 

 observation. 



VI. — April, 1910 : Marked increase of température as com- 

 pared with Mardi 1010. 



It will be noticed that in tliree cases (December 1900, Ja- 

 nuary 1908 and February 1900) the increase of Microspora 

 corresponds to the lowest winter-temperatures, the months 

 concerned moreover being the coldest during the period of 

 observation (,) . In fact during the winter-months proper there 

 is apparently no exception to the occurrence of Microspora 

 being determined by such features of the température {Cf. also 

 the chart on p. 7(3). The matter is différent however with the 

 maxima exhibited by thisgenus at other times of theyear; thus 

 in Mardi 1007, July 1007 and April 1010 there is no plausible 

 connection with temperature-data, although July 1007 happens 

 to hâve the lowest July-temperatures for the period of observ- 

 ation. 



We may next proceed to consider the tliree last-named cases 

 in which the maxima of the Microspora show no obvious rela- 

 tion to température-conditions. The most peculiar of thèse is 

 the maximum in midsummer of 1007. In tins connexion it is to 

 be noticed that May- July of 1007 had uniformly low average 

 maximum and mean températures, so that the température 

 conditions during the summer of 1007 would be more favourable 



(1) There is evidently niuch resenddance between the conditions determin- 

 hil: the occurrence of Microspora and those înfluencing UlothriX (Cf. Klehs, 

 L896, |'. :>U7; Brunnthaler, l'.'iiT, p, 194). 



