398 
only attack successfully those parts of the timber which are already dead and 
exposed to the air; their influence for evil should not be underrated on that account, 
however, for although they are saprophytes living on the wood, their entrance into 
the trunk and branches means more or less rapid hollowing of the heart wood (there¬ 
by rendering the tree liable to be thrown by winds, etc.) and the gradual pro¬ 
duction of injurious substances which soak into the sound parts and pave the way 
for the advance of the destroying mycelium into living organs. Hence, though such 
fungi are saprophytes, strictly speaking, in their local action, they nevertheless act 
toward the whole tree taken as an individual as parasites which may induce dan¬ 
gerous diseases. 
Remedial measures are, of course, to be directed to the careful tending and cover- 
ing ot wounds, a mode of procedure which has long been carried out on various 
trees at Kew and with decided success, I believe. 
This last is a remark which American street and park, commissioners 
and orcliardists might well take to heart. 
Prof. Ward happily avoids the fault of many popular writers. There 
is no effort to conceal ignorance or gloss over difficulties. At every 
turn the reader is informed of the present limitations of knowledge 
and of the necessity for further study. Concerning American fungi 
he writes as follows: 
Farlow and Seymour give a long list of American forms [on the pine] that will 
necessitate much careful investigation before we can determine which are truly 
parasitic and which are saprophytic. 
Alter giving Klebalm's recent conclusions, he says: 
Several other forms of Periclermium are known on various species of pines. The 
following have hitherto been included with the above under the common name 
P. pint, but no one will now be so bold as to retain them until further investiga¬ 
tions have decided as to their relationships. The forms in question occur on the 
cortex of Pinus montana (Mill.), P. nncinula (Ram.), P. maritima (Mill.), P. polepensis 
(Mill.), P. mitis (Mchx.), P. laeda (L.), P. ponderosa (Dougl.), P. rigida (Mill.), P. 
insignis (Dough), P. sabineana (Dough), P. contorla (Dough), and some other Ameri¬ 
can pines, as well as on the leaves ol the Indian P. longifolia (Lamb), and of the 
American P. australis (Mchx.). 
Agaricus nielleus is recorded by Farlow as occurring on Chamcecyparis spliceroidea 
(Spach), and the same authority mentions Botrytis vulgaris on Sequoia; whether 
these are parasitic I do not know, and in fact the whole of the very long list of conifer 
fungi wants careful overhauling before we can decide as to their share in producing 
diseases. 
Fiually, after calling attention to Asterina, Meliola, Coryneum, Dothi- 
dea, Pleosporte, Spliserella, Stigmatea, etc., Prof. Ward makes the fol-' 
lowing very pertinent remarks: 
W ith regard to a large number of these forms, and to even more numerous foreign 
forms, we are as yet quite in the dark as to whether they are parasites or not. 
Experience warns us, however, that in many cases epidemic fungous diseases sud¬ 
denly force themselves on our attention, owing to some form hitherto occurring 
sparsely and known only to the curious expert, having become suddenly favored in 
its struggle for existence. 1 have already given you several examples, notably that 
ol the laich disease, into the life struggles of which we have succeeded in peering 
rather deeply. Surely such considerations should alone suffice to extend and cement 
the sympathy between the practical horticulturist and the persistent though per¬ 
haps unobtrusive investigator, which, I am happy to see, is becoming more and more 
pronounced as each understands better the ways and high aims of the other.— 
Erwin F. Smith. 
