4i8 
HARRY M. FITZPATRICK 
EXPLANATION OF PLATES XXX-XXXII 
All the figures were drawn with the aid of a camera lucida. A Zeiss 2 mm. 
apochromatic oil immersion objective (1.4 N.A.) and an 8 compensating ocular 
were used. As reproduced the figures represent a magnification of about 2150. 
Figs. 1-4. Endophytic hyphae of Eocronartium muscicola in the tissue of 
Climacium americanum. The host cells are merely outlined. 
Fig. I. A fungous hypha showing a single extremely long binucleate cell. The 
deep-staining bodies at the upper end are cytoplasmic granules. The deep-staining 
pads on the transverse septa in this and other figures probably indicate the presence 
of protoplasmic connections. The large, much-elongated host cells are characteristic 
of the main axis of the moss gametophore. 
Fig. 2. A much shorter cell with more minute nuclei; in the same general 
region of the host. 
Fig. 3. Terminal cell of a hypha passing from the interior of a gametophoric 
branch out into the space beneath one of the leaves. The leaf is shown in section 
at the right. The tip of the hypha has turned upward toward the apex of the host 
branch where later it would unite with other hyphae to form the sporophore. 
Fig. 4. Terminal cell of a hypha in the apical region of the host. 
Figs. 5-19. Hyphae in the interior of the sporophore. 
Fig. 5. Unusually short cells with minute nuclei. The cells are binucleate 
and the pads on the septa are prominent. 
Fig. 6. A very long' cell in an adjacent hypha. The cell contains two large 
nuclei, and numerous deep-staining cytoplasmic granules. 
Fig. 7. A pair of nuclei in a cell of one of the hyphae of the sporophore. They 
are in the spirem condition, possibly near synapsis. 
Fig. 8. Another pair of nuclei much smaller in size and possibly in very early 
prophase. Each contains four deep-staining bodies resembling chromosomes. 
Figs. 9-16. Other pairs of nuclei in various stages of conjugate division. 
Figs. 17-18. Four-nucleate cells; the two pairs of nuclei in each cell resulting 
from conjugate division. 
Fig. 19. A terminal binucleate cell on a hypha at the periphery of the sporo- 
phore. Such a cell by division cuts off the young binucleate basidium. 
Figs. 20-45. Basidia. 
Figs. 20-23. Young binucleate basidia. There is considerable variation in 
shape. 
Fig. 24. A young basidium in which nuclear fusion is taking place. * 
Fig. 25. A basidium in which the fusion nucleus still contains two nucleoli. 
Fig. 26. Fusion nucleus at a stage near the resting condition. 
Fig. 27. Fusion nucleus at a slightly later stage showing chromatin aggregated 
into larger masses at the interstices of the network. 
Fig. 28. Spirem thrown into eight definitely thickened loops. 
Fig. 29. Spirem loops less definite. 
Figs. 30, 31. Spirem at one side of nucleus, preceding synapsis. 
Fig. 32. Synapsis; nucleolus enmeshed in the chromatin strand. 
Fig. 33. A spirem giving some indication of a longitudinal split. 
Fig. 34. A segmented spirem. 
Fig. 35. First nuclear division showing four chromosomes; metaphase. 
