EFFECT OF DIPLOID ON HAPLOID MYCELIA 249 



Table V were made a second and then a third time, with essentially 

 the same results as before. In each of thb new sets of experiments. 



Fig. 136. — Coprinus lagopus. An illegitiinate mating of a large haploid 

 mycelium with a small diploid inoculum resulting in the diploidisation 

 of the haploid mycelium ; to show the " patchiness " of the diploid 

 mycelium into which the haploid mycelium has been converted. A 

 haploid mycelium {AB) was allowed to grow on cleared dung-agar in 

 a Petri dish until it was 6 • 2 cm. in diameter. It was then inoculated 

 at its periphery (right-hand side) with a tiny liyphal mass of a diploid 

 mycelium {Ab)-\-{aB). The diploid inoculima soon began to diploidise 

 the large haploid myceliimi ; and, four days after inoculation, hyphae 

 bearing clamp-connexions could be observed all around the periphery 

 of the large originally-haploid central mycelium. The photograph was 

 then taken. The diploid myceliiun around the central mycelium is 

 very " patchy " and therefore contrasts with the diploid mycelium 

 produced in experiments made in a similar manner but with legitimate 

 combinations of haploids and diploids (c/. Figs. 120 and 127). 

 Natural size. 



the combinations [AB) x {Ab)+{aB) and [Ah) X {AB)+{ab) again 

 yielded a partial diploidisation of the haploid myceha, whereas in 

 the combinations («6) X {Ab)+{aB) and {aB) X {AB)-^{ab) the 

 haploid mycelia remained in the haploid condition. 



We may ask : how in Experiments No. 1 and No. 3 of Table V 



