SEXUAL REPRODUCTION. 



175 



tnelanoloma, he was more successful with Peziza ompJialodes. 

 As early as 1860 he recognized the large globose, sessile, and 

 grouped vesicles which originate the fertile tissue, but did not 

 comprehend the part which these macrocysts were to perform. 

 Each of these emits from its summit a cylindrical tube, generally 

 flexuous, but always more or less bent in a crozier shnpe, some- 

 times attenuated at the extremity. Thus provided, these utricles 

 resemble so many tun-shaped, narrow-necked retorts, filled with 

 a granular thick roseate protoplasm. In the middle of these, 

 and from the same filaments, are generated elongated clavate 

 cells, with paler contents, more vacuoles, which Tulasne names 

 paracysts. These, though produced after the macrocysts, finally 

 exceed them in height, and seem to carry their summit so as to 

 meet the crozier-like prolongations. It would be difficult to 

 determine to which of these two orders of cells belongs the 

 initiative of conjugation. Sometimes the advance seems to be 

 on one side, and sometimes on the other. However this may be, 

 the meeting of the extremity of the 

 connecting tube with the summit of 

 the neighbouring paracyst is a con- 

 stant fact, observed over and over 

 again a hundred times. There is no 

 real junction between the dissimilar 

 cells above described, except at the 

 very limited point where they meet, 

 and there a circular perforation may 

 be discerned at the end, defined by a 

 round swelling, which is either barely 

 visible or sometimes very decided. 

 Everywhere else the two organs may 

 be contiguous, or more or less near to- 

 gether, but they are free from any adherence whatever. If the 

 plastic matters contained in the conjugated cells influence one 

 another reciprocally, no notable modification in their appearance 

 results at first. The large appendiculate cell seems, however, to 

 yield to its consort a portion of the plasma it contains. One 

 thing only can be affirmed from these phenomena, that the con- 



Fin. 100. Conjugation in Peziza 

 ompltalodes. (Tulasne.) 



