EFFECT OF DIPLOID ON HAPLOID MYCELIA 261 



the isolated inocula (AB) and (ab). The time-data for Experiments 

 Nos. 1, 2, and 4 of Table IX resembled those just given for 

 Experiment No. 3. 



Concluding remarks on the three series of experiments. Assuming 



Fig. 138. — Coprinus lagopus. Progress of the diploidisation process in 

 an illegitimate combination of a large haploid mycelium {AB) 

 inoculated at three places on its periphery with : an isolated 

 haploid mycelium (Ab) ; an isolated haploid mycelium (aB) ; and 

 a pair of haploid mycslia (.46) and (aB), set close together so that 

 they could soon diploidise one another and so build up in situ a 

 diploid inoculum for the [AB) mycelium (c/. Fig. 137). The 

 drawing, made from wax-pencil tracings on the base of the Petri 

 dish, shows the progress of the experiment on the third day after 

 inoculation. Tlie lower pair of inocula {Ab) and {oB) first diploidised 

 one another, and now the diploid mycelium so produced is diploid- 

 ising the large central {AB) mycelium in the directions shown by 

 the curved arrows. The peripheral hyphae of the {AB) mycelium 

 show clamp-connexions as far from the lower pair of inocula as is 

 represented by the heads of the curved arrows. Later on, when 

 the {AB) mycelium became further diploidised, it diploidised the 

 two upper haploid mycelia {Ab) and (aB). Drawn by A. H. R. 

 Buller and Ruth Macrae. Natural size. 



that the development of clamp-connexions and a change to narrow- 

 angled branching by a haploid mycelium are indications that the 

 haploid mycelium is becoming or has become diploidised, the results 

 of the three sets of experiments recorded in this Section show 

 quite clearly that, in illegitimate combinations, a diploid myceUum 



