r 
MONOGRAPH OF THE LABOULBEXIACE.E. 2ll 
teen days, according to the temperature at which they were kept; nnd it is cerdunly 
improbable that many forms attain maturity in a much shorter period ihan tliis. 
- B 
In regard to the longcdty of individuals, it seems qiiife certain that those which 
have been mature in the autumn^ may still produce spores during the spring and (^arly 
summer; for although mature specimens which have hibernated are a^it to be much 
damaged, and are often no longer fertile, fully mature individuals, evidently of consid- 
erable age, from their dark color, have been found on hosts still hibernating and col- 
lected by '^sifting" early iii the spring before the advent of warm weather. That 
the germinating spores and young individuals live over winter, attached to their hosts, 
in a dormant condition, is an undoubted fact; and it is upon the survival of those, 
rather than on that of the maturer individuals, that the fungus depends for its perpet- 
uation. That a majority of forms, occurring in temperate climates, live throughout 
the summer and early autumncannot be doubted ; since one very rarely finds Individ- 
uals that are old and infertile. When such cases occur, with few excerptions (a.« in 
Amorphomyces), the cessation of fertility has evidently resulted from some vioh-nt 
injury which has destroyed tlie perithecinm, or a portion of it. From my own ol)ser- 
vations in this connection, 1 think that it may be safely assumed that, in a majority 
of cases, the life period of the parasite coincides with that of the host. The number 
of spores formed by a single individual must therefore be often enormous, in view of 
the flict that the ascogenic cells are continuously active during the growing season. 
GEOGRArniCAL Distribution. Any intelligent discussion of the distribution of 
the LaboulbeniaceoD is hardly possible, since it is in North America only that their Fys- 
tematic study may properly be said to have commenced ; yet, judging from the small 
number of exotic hosts which have been available for examination in connection with 
the preparation of the present monograph, it may be inferred that the warmer portions 
of the earth are quite as rich in representatives of the group as are the more tcmjier- 
ate regions, while towards the colder northern latitudes they become distinctly lo5=s 
abundant. For, although specimens have been examined from localities as far north 
as Hudson's Bay and the Aleutian Islands, a com pa rati vel}- small percentage of the 
hosts collected in these regions appear to be infested, while the reverse is true as the 
portion of the United States is approached. N 
f; 
he CarabidtB and Staphylinida?, families of beetles which furnish by far the majority 
f the hosts at present known, are relatively much less abundant in tropical than they 
re in temperate regions, it seems highly probable that, in such localities, these orders 
re replaced by numerous other insects having suitable life-conditions, among which 
16 
