1905.] De velopment of the Ascocarp o/*Humaria granulata. 367 



24. Oltmanns, F. " Ueber die Entwickelung der Perithecien in der Gattung 



Chsetomiuni," ' Bot. Zeit.,' vol. 45, 1887, p. 192. 



25. "Woronin, M. "Zur Entwicklungsgeschichte des Ascobolus pulcherrimus, Cr. usw.," 



' Beitr. zur Morphol. u. Physiol, der Pilze, Zweite Eeihe,' 1866, p. 1. 



26. Van Tieghem, Ph. " Culture et deVeloppement du Pyronema confluens," ' Bull, de 



la Soc. Bot. de France,' voL 31, 1884, p. 35. 



EXPLANATION OF PLATES. 

 Plate 13. 



Fig. 1. — Portion of mycelial hypha showing the nuclei, and deeply-staining granules on 



the transverse wall, x 1900. 

 Figs. 2a and 2b. — Two young archicarps growing up from the general mycelium : fresh 



preparations, x 430. 

 Fig. 3. — Slightly older archicarp in section, x 430. 



Fig. 4. — Archicarp showing the vegetative hypha 1 beginning to grow out from the cells 

 beneath the ascogonium. The granules on the wall are clearly visible, x 620. 



Fig. 5. — Young ascocarp in which the ascogonium and the sub-terminal cells of the 

 archicarp are covered in by the vegetative hyphae. x 430. 



Fig. 6. — Section of young ascogonium showing ascogonial nuclei, x 1050. 



Fig. 7. — Section of slightly older ascogonium. x 1050. 



Fig. 8. — Section of ascogonium and basal cell of archicarp which have just become 

 covered in by the vegetative hypha?. The vegetative as well as ascogonial 

 nuclei are clearly visible, x 1050. 



Plate 14. 



Fig. 9. — Section of ascocarp of about the age shown in fig. 5. The granules in the 

 ascogonium and the partial emptying of the stalk cells are to be clearly seen, 

 x 430. 



Fig. 10. — Section of upper part of young ascocarp showing ascogonium partly filled with 

 nuclei and " basal cell " below. Three ascogenous hypha? can be traced 

 throughout their whole length, while portions of others are visible among the 

 vegetative plectenchyma. Nuclei are to be faintly distinguished in the " basal 

 cell " and some of the vegetative cells, x 1050. 



Fig. 11. — Section of somewhat older ascocarp showing the ascogonium and three stalk 

 cells. The majority of the nuclei have already migrated from the ascogoniuni. 

 x620. 



Fig. 12. — Section showing the nuclei in the basal cell and the cells immediately 

 surrounding, x 1050. 



Fig. 13. — Section through the lower part of the ascogonium and the upper part of the 

 basal cell showing the curious granular masses on the transverse wall, x 1010. 



Fig. 14. — Two female nuclei of the ascogonium in the process of fusion, x 2700. 



Fig. 15. — A group of ascogonial nuclei with a fusion-nucleus showing nucleoli in act of 

 fusion, x 2700. 



Fig. 16. — A group of nuclei of ascogonium with a large-fusion nucleus with two nucleoli, 

 x 2700. 



