1914] GATES—XEROPHILY 475 
experiments is grouped together, and each figure represents at 
least two determinations. 
TABLE V 
SUMMARY OF SUMMER EXPERIMENTATION (1912) ON RATE OF CONDUCTION OF PEAT 
BOG PLANTS; RESULTS IN CENTIMETERS PER HOUR 
July 6 | July 6 | July 8 July 9 
IMI SN die eis «ae au" =: as” s 26° ; 
ann. backdee fig ee oe ee 50] t|48p 69p ti6or 
Chamaedaphne calyculata.............. 12 20 13 22 
Andromeda fdasnate anh Megs recs ea. V5 peel Oeisnend pawaur hag ie elena 
Va BORDON obit: oe Mg oo Penge Meine sa 
VacGohin seer set CPO Pee eg oe eee aes oo ees glee 
ROR a sh ea ak fa i A a 
WOM WNGE os oe a pinch eee MO beds paces ie 
Es ecg gi goad Ee He EEE ee aber gE ES ae Ege oe io eg Caryh easaapee a oteane x 
Cephalanthus a eet ee (27*) OPE eae eo gee (170*) 
Aronia mi saeco Rah etek pecs 4 ad Bl ea eee. oe nea mre 108 
ere mcrae 8 a Pg 1 St Me Ce, Marenenpe 
Nemo aes Tahoe ap a NN A Pg EN ee ae an ne 
sume SACO a a PL BO ES ip ee ny 
peCUA Vana ee ee i tek ay 180 
meodium thelyptetis. 25. 4.2. .5 2.3 fag ab cia pemrcamery Pouce gerornee 66 
Asclepias eo _ See as Pe eee ee ori ee oe Pe as oe 2 “a 
Eupatorium perfoliatum (wilted)........|......00.{eceececee[eceeeeees 4 
Sagittaria latifolia — ry oe aes ee i Pe ac ee aie oa Bhs Be eg By 
es Cor as ee a eee ade eee 
ieaigee cleat Tce ee ee ipa ee he ee pan sia eel ooh ae eee s 86 
Typha latifo ae Be ee oe ee ees Cs fee oa oe 114 
Care fo eh she a ny ck 90 
Sarracenia Gace Ri oe ea ee er ee eres asleep a eee 102 
*Figures followed by an asterisk and inclosed in mae indicate that the lithium nitrate had 
reached the tip of the stem within the time of experimentatio 
From an inspection of the data of table V it is readily seen that 
the evergreen ericads experimented with are all characterized by 
a low rate of conduction, decidedly low in comparison with that of 
both herbaceous plants and other shrubs. The rate of conduction 
was markedly lower in the evergreen bog trees than it was in the 
deciduous bog trees. Southern swamp shrubs showed a higher 
rate of conduction than northern bog ones. 
Relation of summer to the xerophily of peat bog ericads 
During the summer all the peat bog plants are actively carrying 
on the work of the growing season and have their greatest need of 
water. Especially at the beginning of the growing season the soil 
