20 PKOTISTS AND DISEASE 



oospore ; the fused gametangea of Mucor, &c., form a 

 zygospore. 



When the spore of a fungus germinates by the formation 

 of a promycelium from which arises reproductive elements 

 different in shape from the ordinary conidia they are called 

 sporidia. 



Nomenclature. It is imperative that there should be a 

 uniform system of names in biology. The binominal or 

 Linnaean system is universally adopted. Linnaeus (Carl A 

 Linne, 1707-1778) defined his system thus: 



"Diagnosis sic plantae consistit in affinitate Generis et 

 in discrimine Speciei. Nomen plantae itaque, ut utramque 

 diagnosin indigitet, duplex erit : Genericum, cognomen 

 gentilitium. Specificum, Praenomen triviale. ' ' 



At the International Botanical Congress, 1905, it was 

 recommended that specific names begin with a small letter, 

 except those which are taken from names of persons (sub- 

 stantives or adjectives) or those which are taken from generic 

 names. This was to apply to the vascular plants in particular. 



The Medical Research Council (' Notes upon the Pre- 

 paration of Monographs, &c.,' 1921) directs that all specific 

 names be written with a small initial letter, even when they 

 are formed from the names of persons or places. This is 

 the practice in zoology. Thus in the British Museum ' Guide 

 to the Mycetozoa ' (1919) we read Diderma Trevelyani, and 

 Eeticularia Lycoperdon ; and, in zoology, Trypanosoma 

 brucei, and Spirochaeta anodontae. The latter method has 



