RATE OF MOVEMENT OF NUCI>EI 



215 



inoculated with (.46) and {Ab)+{aB). After inoculation the eight 

 plates were kept under a bell- jar on a laboratory table at room 

 temperature (about 22° C). 



In all of the eight pairings, the large central haploid mycelium 

 became completely diploidised (as shown by the appearance of 

 clamp-connexions) by the tiny haploid or diploid inoculum within 



iojinc mLfwoicL vmcmumi 



I 



fiafiunjcL 

 diuvUnxL 



cLculu uTvcAJumsmU 

 of cywwWj 



Fig. 124. — Coprinus lagojyus. Diagram to illustrate the beginning of a mating 

 experiment. A large haploid mycelium lias been growing on dung-agar in 

 a Petri dish for nine days. The circles Nos. 2-9 show its boundary at 

 tlie end of the second to the end of the ninth day. A tiny hyphal mass 

 of another haploid mycelium of opposite sex or of a suitable diploid 

 mycelium, called the inoculum, has just been set a little way from the 

 periphery of the large haploid mycelium. Drawn by A. H. R. Buller 

 and Ruth Macrae. Natural size. 



four days. Between the time of inoculation and the time of just- 

 completed diploidisation, the large haploid myceha increased their 

 diameter from 5 • 5-6 • 2 cm. to 8 • 5-0 • 3 cm. 

 Photographs of three of the eight pairings : 



No. 1, {AB) X (ft6), 



No. 2, {AB) X {AB)+{ab), and 



No. 6, {Ab) X {Ab)+{aB), 



taken five days after the large central haploid mycelium was inocu- 

 lated at its periphery and from one to two-and-a-half days after the 

 large haploid mycelium had become completely diploidised all 



