Studies on Caryospora Putaminum

SUMMARY

1.	Best growth and production of perithecia of Caryospora putaminum occurred when cultures were grown at 25–28° C. on malt agars adjusted within the pH range of 5.0-6.0.
2.	Growth on pea-extract agar differed in color from that on malt-extract agar. Spermagonia and spermatia occur readily on the former with perithecia occurring only occasionally; on malt agar perithecia occur readily while spermagonia and spermatia are only of occasional occurrence.
3.	Spermatia do not appear to be absolutely necessary for sexual reproduction and apparently are not concerned in dissemination.
4.	Asci arise with or without crozier formation.
5.	The most common number of spores per ascus is three, but from one to seven may occur.
6.	A young three-spored ascus was observed to contain one nucleus per spore with five nuclei remaining in the epiplasm. Apparently the nucleus included in each spore divides and a median septum forms which gives rise to a two-celled ascospore, each cell of which contains one nucleus.
7.	Most mycelial cells are uninucleate, but some appear to be multinucleate.
8.	Division figures in paraphyses indicate a chromosome number of three or four.
9.	Caryospora minima is proposed as a new species. It differs from other species of this genus mainly in spore size and shape.
10.	Asci of Caryospora minima arise mainly by crozier formation and contain eight ascospores when mature. Each spore has two main cells and contains one nucleus per cell.