FIFTEENTH REPORT. 
104 
mountainous. Small areas of undulating sandy moraines are frequent. 
About 25 miles west of Sault Ste. Marie the D. S. S. & A. Ry. passes 
lor several miles through one such area which is wooded almost ex- 
clusively with jack pine, a most interesting sight to the phytogeographer, 
however uninviting it may be to the agriculturist. (The government has 
taken advantage of the uninhabited condition of this area in creating 
there the “Marquette National Forest,” the southern border of which is 
skirted by the railroad.) 
Most of the distance between Sault Ste. Marie and Trout Lake the 
surface is formed by a thick deposit of lake clay, in which the ground- 
water level lies deeper than it does on other parts of the route, as in- 
dicated by the fewer bogs and deeper stream valleys. Farms are rather 
common there, and Ihe country much more densely populated than that 
traversed on the eastward journey. 
Even where there are no farms in sight the lumbermen have been 
active in years gone by, as they have nearly everywhere else in Michi- 
gan, and have doubtless removed most of (lie white pine and a good deal 
of tin 1 oilier timber which made up the original forests. However, there 
is still enough native vegetation left to keep an observer busy writing 
plant names every moment while the train is in motion, which cannot 
he said of some places farther south. 
The following list contains the names of all the plants identified more 
than once from the train on the whole journey of 135 miles. Of course 
it does not do justice to the herbs, but it ought to be reasonably com- 
plete for the trees, which are the most important part of the vegetation, 
not only from an economic and esthetic standpoint, but also ecologically, 
for they are subject to a greater variety of environmental conditions 
than the herbs are, on account of their larger size and longer life. (For 
example, Ihe absolute minimum temperature may determine the north- 
ern limits of some trees, for they are exposed to all (he weather there 
is; but it is probably immaterial to the herbs which are dormant be- 
neath the ground and often also covered by snow when the minimum 
temperature occurs.) 
The numbers prefixed to the names of the species indicate the number 
of times each was observed, between different mile-posts, except that 
where a species was noted as very abundant I have counted it twice in 
tabulating the returns. This method of quantitative analysis of vege- 
tation is of course very crude, hut it is much better than a mere quali- 
tative list of the usual type; and it would probably take a person cover- 
ing the same ground on foot at least a week to get more accurate re- 
sults than T did in a few hours. 
It is difficult enough to distinguish our two common species of Picea 
mi close inspection (much more so for example than in the case of the 
two southeastern species of TaxorHum , which many dendrologists still 
refuse to regal’d as distinct), and almost impossible to do so from a 
moving train, where one has to look pretty sharp even to distinguish 
Pi oca from Abies. 1 have therefore combined the figures for the two 
Pioras, and assumed that they both belong between 41 and 20. 
The names of evergreens are printed in bold face type, for reasons 
which will appear presently, and those of weeds are put in parentheses, 
The nomenclature used is mainly that of Robinson and Fernald’s Manual 
(the so-called seventh edition of Gray’s). 1008. 
