126 RECOKD OP CURRENT RESEARCHES RELATING TO 



The air-chambers are not formed by a separation of cells, nor by 

 a splitting advancing from without inwards, but represent depressions 

 of the surface, formed by particular portions becoming overgrown by 

 the more rapid growth of the adjoining parts. They become sub- 

 sequently completely covered in, though usually with a small opening 

 outwards. 



The ventral scales are entirely wanting only in Riccia crystallina. 

 The origin and development of these scales is, according to the 

 author, very different from that of the organs of Marchantieae called 

 by the same name. 



Fungi. 



Propagation of Sphaeria (Gnomonia) fimbriata (Pers.). * — 

 In December, 1878, Mr. C. B. Plowright planted two small specimens 

 of hornbeam {Cmyinus Betulus), which had still attached to their 

 branches the withered leaves plentifully attacked by the Sphceria. 

 Owing to the removal, the old leaves fell off, and were blown away 

 long before the green leaves burst their buds at the end of May. 



On the 1st June, he tied four fragments of a leaf, each of which 

 contained a cluster of perithecia with mature sporidia in theio, upon 

 four places of one of the hornbeams — between the leaves of a terminal 

 bud. On 12th July, numerous minute black specks were visible upon 

 the leaves, and the infecting fragments were I'emoved. In due course 

 the black spots developed into typical specimens of Sphceria Jimbriata. 

 Up to November no further development of the Spliceria took place. 

 This is the more noteworthy because the shrub which was not subject 

 to experiment had, when first planted, the greater number of affected 

 leaves upon it, but the parasite has not shown itself on a single leaf 

 this year (1879) ; nor on the other hornbeam has a single perithecium 

 developed itself save at the points inoculated. 



This confirms Dr. Max Cornu's conclusion, that these ascigerous 

 parasites are confined to the deciduous foliaceous organs, a conclusion 

 arrived at in experimenting with Rliytisma acerimim.'f 



These observations are not without interest in showing the con- 

 nection which exists between the Phacidiacei and the Splicer iacece, 

 physiologically as well as structurally, and afford an explanation of 

 the abundance of Sphceria Jimbriata where it occurs, as compared with 

 the allied species, S. Coryli, the hornbeam being a tree in which the 

 dead leaves remain attached to the twigs, as a general rule, well 

 through the winter and into the spring, until the sporidia arrive at 

 their most perfect state of maturity. 



Sclerotium of Claviceps.l — A. Eenner has afresh investigated 

 the development and histology of the sclerotium of Claviceps, of 

 which the following is a summary : — The sclerotium consists, for the 

 larger part, of large polygonal cells, filled with drops of oil, and firmly 

 united in their growth, constituting the so-called pseudo-parenchyma. 



* 'Grevillea,' viii. (1879)p. 68. .' 



t. See this Journal, i. (1878) p. 265. 



% ' Wandersammhing ungarischer Aerzte u. Naturforscher zu Budapest ; 

 naturwissenschaftliche Sectiou, Aug. 30, 1879'; see 'Bot. Zeit.,' xxxvii. (1879) 

 p. 677. 



