Ohseroations on Camarosporium Abietis n. sp. 151 



good for the lower shaded branches. If, therefore, complete 

 defoliation occurs prior to the third year it is either the result 

 of disease or death of the tissues from some other cause. 



In an endeavour to ascertain whether the mycelium of the 

 fungus penetrated h\-ing host tissues, it was decided to section 

 li\ing t\\'igs which were bearing leaves on all but the current 

 3'ear terminal shoots, the latter portions being clearly infected 

 and e\ddently dead. Examination of the sections showed that 

 the dead portions were infected and that h\'phae could be traced 

 close up to the junction of completely dead and still h\'ing tissue, 

 but no penetration of still active li\-ing cells was found to take 

 place, and infection of the cells, therefore, appears to be possible 

 only after they have died. 



Webster (4) maintains that Abies Lowiana has proved ex- 

 ceedingly hardy in Britain and one would suppose, therefore, 

 that it should fee free from frosting. The current year has seen 

 some severe late and early frosts, notably those of June and 

 September, and it would be un\\ise to say that these have had 

 nothing to do \rith the IdUing of young current-year wood. 

 Moreover, many of the needles of the tree in question bore the 

 browned tips which are more or less characteristic of frosting 

 and many still uninfected shoots were found minus their bud- 

 apices as if the latter had been nipped. In the meantime, there- 

 fore, until infection experiments, which are being carried out, 

 give a definite result one way or another, it may be taken that 

 the fungus is saprophytic. 



BIBLIOGR.\PHY. 

 (i) Allescher, a. — In Rabenhorst, Kr\-ptogameii Flora von Deutschland, 

 Oesterreich und der Schweiz. Zweite Auf., Bd. i, Abt. vii. Leipzig, 1901. 



(2) PoTEBXiA, A. — Mvcologische Studien. Ann. ^Mycol. vol. v, 1907, p. i. 



(3) S.\cc.\RDO, P. A.— Sylloge Fungorum. Vol. iii, Patavii, 1884. 



(4) Webster, A. D. — Coniferous Trees. London, 1918. 



EXPLAXATIOX OF PLATES III AND l\' . 

 Fig. I . A young fructification shoeing paler area in centre of apex, x 40. 

 Fig. 2. Spore-forming la5-er showing a. young, b. mature spores, c. sporophores 



becoming mucilaginous, x 135. 

 Fig. 3. A mature fructification showing a. mature spores, b. residual non- 

 spore-forming pseudoparench\-ina, c. basal stroma-like area, x 50. 

 Fig. 4. Two mature fructifications on a common stroma, x 30. 

 Fig. 5. Mature spores and their sporophores. a. a rather uncommon rounded 



tj'pe, b. immature one-ceUed spore containing oil-globules, c. and d. t\"pical 



spindle-shaped spores, x 312. 

 Fig. 6. Immature spore with the two first formed cross walls, x 312. 

 Fig. 7. Spores in mucilage after escape from the fructification, a. elongated 



portions, b. ring-hke portions, c. spores, x 225. 

 Fig. 8. Early stages in germination, a. papiUa-hke outgrowth appearing, 



k. outgrowth enlarging, c. a very young germ-tube, x 312. 

 Fig. 9. Germinating spores after 24 hours in culture solution, x 312. 

 Fig. 10. Germinating spores after 72 hours, a. spore about to germinate at 



both ends, b. showing a median cell germinating, c. end cells germinating. 



X 312. 

 Fig. II. Mycelium with spore-forming apices, x 240. 

 Fig. 12. MyceUum bearing spores, a. and c. mature, b. immature, x 240. 



