1 6 BOTANICAL GAZETTE [july 



region of contact between the gametes. They usually lie in parallel 

 hyphae with their lateral walls in contact, and when they are in this 

 position and are of equal height, the initial point of dissolution is 



middle 



small 



is first formed. Figs. 4 and 5 are of early fusion stages between 

 gametes of P. Claytoniata, and fig. 20 between those of P. Violae. 

 As a rule, the dissolution of the walls continues on all sides of this 

 pore until practically all of the adjoining walls have been dissolved 

 away. Figs. 6, 16, 17, 21-24 show this condition in various forms. 

 Fig. 23, of P. Hydrocotyles, is of especial note since three fusions are 

 shown clearly within a small area. The figure shows further that 

 the fusing cells have no definite position in the hypha or tissue in 

 which they are borne. The two gametes on the right lie immedi- 

 ately beneath the pseudoparenchyma. Those in the center are 

 considerably deeper in the tissue and are the third and fourth cells 

 below the pseudoparenchyma of the respective hyphae in which 

 they are found, while the pair on the left is placed midway between 

 the others. A binucleated basal cell lies above the left gamete of 

 this pair. 



from 



forms in that the gametes 



hyphae at the base of the cup. A completed fusion between two 

 such gametes is shown in fig. 24, and just above this lies the base 

 of a two-legged basal cell. The upper part of the basal cell has 

 been cut off in sectioning. The right gamete of the basal cell is 

 the adjoining cell in the same hypha with the upper gamete of the 

 fusion cell. Four layers of horizontal hyphae are found between 

 the fusion cell and the host cell that marks the lower boundary of 

 the sorus. According to Hoffman (15), the gametes of Endophyl- 



Semp 



similar 



stages in P. Eatoniae. 



When the fusion of the gametes is completed, the fusion cell 



ermis and the nuclei mo\ 



into the 



27). In P. Eatonia* 



gametes 



the 



The 



