SPELER1A. 



[ 702 ] 



SPH^RIACEI. 



This is common on beech trees. S. con- 

 vergent (figs. 647, 648) is an analogous form. 

 S. elongata (figs. 655-657) affords an example 

 of those species which are at first immersed 

 and adnate, and finally burst forth and 

 become nearly free. 



Fig. 647. 



Fig. 648. 



Sphaeria convergens. 

 Magnified 20 diameters. 



Fig. 649. 



i 



Sphseria verrucosa. 

 Magnified 20 diameters. 



For species now separated from this genus 

 see CLAVICEPS, HYPOXYLON, XYLARIA, 

 HYPOCREA, and NECTRIA. 



Certain points of great interest have lately 

 been ascertained respecting this genus and 

 its allies, which are mentioned under the 

 heads of the family and other genera, namely 

 the coincidence and evident connexion be- 

 tween true species of Sphceria and various 

 Coniomycetous Fungi ; for just as Melasmia 

 is a precursory form of Dotliidea, Tubercu- 

 laria of Nectria, &c., Cytispora, Septoria, 

 and other forms precede Sphceria, and many 

 distinct stylosporous forms are associated, 

 usually described as belonging to distinct 

 genera, such as Stilbospora, Sporocadus, 

 Sphceropsis, &c. Thus these plants seem to 

 produce three kinds of reproductive organs, 

 as is now known to be the case with the 

 Uredinei, viz. : (1) a form analogous to the 

 spermogonia of the Lichens (in Sphceria 

 represented by Cytispora, &c.) ; (2) an 

 ascophorous fruit, the perithecium of the 

 true Sphceria ; and (3) a stylosporous fruit, 

 representing the genera Stilbospora, Sporo- 

 cadus, &c. 



S. Laburni has been found by Tulasne to 

 exhibit all these stages, namely perithecia 

 containing asci surrounding a cytispore, 

 with other conceptacles on the same stroma 

 resembling the perithecia, but lined with 

 stylospores instead of asci. Berkeley and 



Broome also describe the existence of the 

 perithecia of Sphceria inqulnam and the 

 conceptacles of Stilbospora . macrosperma on 

 the same stroma (PI. 26. figs. 25-28). 



It is stated by Tulasne that the spermatia 

 of the cytisporous forms may be contempo- 

 raneous with the stylospores brbasidiospores, 

 but they always precede the ascospores in 

 their development ; hence there is ground 

 for supposing that they represent the sper- 

 matozoids of the higher Cryptogamia. 

 With regard to the relations of the stylo- 

 spores, it is possible that they are merely 

 modifications of the ascospores ; but it 

 would appear probable that they must be 

 regarded as real gonidial structures, for 

 which it may be desirable to retain Fries's 

 name of conidia, just as that of tetraspores 

 is retained among the Florideous Algae. 

 Attention should be directed here to the 

 complete correspondence between the series 

 of forms of these genera and those of the 

 UREDINEI, where, as in PUCCINIA, we 

 have the spermogonium (cytispore), the 

 uredo (stylosporous fruit), and the perfect 

 fruit, (perithecium). See also CONIOMY- 

 CETES. 



Currey has published some extensive 

 observations on the spores of the Sphcerice. 



BIBL. Berk. JBr. Fl ii. pt. 2. 232 ; Ann. 

 N. H. i. 205, vi. 360, 2. v. 374, vii. 186; 

 Hook. Jn. Hot. iii. 319 ; Fries, Sum. Veget. 

 388, Syst. Mycol ii, 319; Tulasne, Ann. 

 So. N. 3. xv. 375 (Ann. N. H. 2. viii. 117), 

 4. v. 108, viii. 35; Currey, Mic. Jn. 1855, 

 iii. 263, Linn. Tr. xxii. 257. 



SPH^ERIACEI A family of Ascomy- 

 cetous Fungi, containing a vast number of 

 parasitic plants, mostly of minute dimen- 

 sions, growing upon leaves, stems, bark, 

 wood, &c., and sometimes on the bodies of 

 insects. The essential distinctive character 

 lies in the globular, ovate, or flask-shaped 

 conceptacle or perithecium^ containing asci, 

 which ultimately opens by a pore at its 

 summit to discharge the spores. These 

 perithecia occur either solitary or in groups 

 on an indistinct matrix, growing out from 

 the epidermis of leaves, &c. (Sphceria) ; or 

 they are immersed in a tubercular stroma 

 (Nectria) , while in the larger forms the 

 stroma becomes developed into an erect 

 clavate or bushy structure, of fleshy or 

 horny consistency, the perithecia being 

 imbedded in the superficial layer of this, 

 and opening by pores on the surface. Much 

 remains to be done in reference to the 

 history of this family, not merely on account 



