144 



PROTISTS AND DISEASE 



In a section of a sporangium of Lycogala Vonwiller found 

 that the nucleus of every spore had beside it a small darkly 

 staining body which he terms a sphaeroplast ; A. Lister 

 described the same body in 1893. 



The nucleated substance left in the stalk and to some 



mm 



*>^A 



M 



FIG. 41. NUCLEI IN SPORANGIA OF ARCYRIA INCARNATA. 1, Stage with 

 many small nuclei and finely granular plasm ; 2, a nucleus from 1 ; 

 3, stage with fissured plasm and larger crescentic nuclei, an early 

 stage of capillitium-tube present : 4, the first mitosis, blunt-ended 

 spindles, capillitium-tubes formed ; <5, the second mitosis, sharp- 

 ended spindles, a capillitium fibre apparently being formed by con- 

 fluence of granules ; 6, two nuclei more magnified ; 7, nuclei of 

 individual spores formed, spores not yet separated, a fully-formed 

 capillitium-tube ; 8, individual spores separated. 2 and 6, X 1000 ; 

 the rest, X 500. 



extent in the hypothallus of Arcyria appears to be a simple 

 residue, the nuclei having the characters of resting nuclei. 

 They may perhaps be compared to the nuclei of Mucor that 

 remain in the conidiophore. 



Jahn has found many small degenerating nuclei in 



