1859.] SPORIDIA OF FUNGI. 113 



thus accounting for its occurrence in my correspondent's gardeUj 

 who, though fquite 'satisfied of this fact, is at a loss to discover 

 the favourable circumstances which stimulated the vegetation of 

 the seeds after remaining in a dormant state so many years. 



I. GiFFORD. 



SPOEIDIA OF EUNGI. 



On the Sporidia of several Ascomycetous Fungi. 



By Archibald Jerdon. 



In Dr. GrevUle's beautiful work, ' Scottish Cryptogamic Flora,' 

 the sporidia of several Fungi of the Order Ascomycetes are not 

 very correctly represented, and I am induced to mention two or 

 three instances, as I have paid a good deal of attention to Fungi 

 of late. It is no disparagement to the author of that admirable 

 work that in some cases he has failed to depict aright the in- 

 ternal structure of some Fungi, for in these plants microscopic 

 examination is often confused and unsatisfactory, unless they are 

 exactly in a state of maturity, in which state it is sometimes 

 difficult to find them. 



In his figure of Xyloma acerinum (now Rhytisnia acerinum), 

 the common Fungus which appears in the form of black spots on 

 almost every Sycamore-leaf, Greville represents and describes 

 the sporidia as " very minute and oval." But if the Fungus is 

 examined when the fruit is in perfection, it will be found that 

 they are very long, of a cylindrical or, rather, filiform shape, and 

 acuminate at the extremities. This Fungus does not generally 

 perfect its fruit till the following spring, and I have this year 

 (1858) found it in full perfection in the month of May, with its 

 discs open, and discharging its sporidia in clouds. 



Another instance occurs in the figure of Sph(Bria typhina [Do- 

 thidea typhina, of Hooker's English Flora), the curious orange- 

 coloured production which is found in summer, investing the 

 culms of various Grasses with a covering of from two to three 

 inches in length. In this, I think, Dr. G. has represented the 

 sporidia as asci. The latter will be found to be somewhat cla- 

 vate (as these bodies generally are), and to be filled with elon- 



N. S. VOL. III. Q 



