220 BOTANICAL GAZETTE [MARCH 
Growth irregularities in individuals have been noted by others, 
although their results are in some cases to be questioned because 
they were based on external measurements alone. Such are those 
of CHRISTISON (5), VON Mout (25), and Josr (13), reference to 
whose work has already been made. The results of TH. HARTIG 
(12) and Rost. Hartic (10) can have no significance in this con- 
“nection, inasmuch as individuals were felled to secure data and 
consecutive measurements were quite impossible. MIscHKE (24), 
as already noted, employed an increment borer, and his results, 
with those of WIELER (39) who pursued the same method, are more 
reliable though not as accurate as is desirable. The former made 
comparative notes on Norway spruce and Scotch pine, and his 
results clearly indicate growth fluctuations. WuirLEeR subjected 
TABLE J 
GROWTH OF WHITE PINE AT DRESDEN, GERMANY 
I II Ill 
Date 1894 
Ring breadth No. of Ring breadth No. of Ring breadth No. of 
mm... acheids mm. tracheids mm. acheids 
April PE oc ew oedac tere rales rr heen Ee koe 0.48 13-14 
May 5 gig acai hursiars gists @ os Pees aed un UGG ues ee Lore a 
May 16 0.08 ee 0.14 8-10 2.44 47 
May 26 Lost SOVETHE Gooey ea loo wey ee 2. 47-59 
June 5 O.1I 3- 4 |0.18-0.20 4-6 4.12 89 
June 16 0.06 2- 4 0.12 6-9 2,35 72 
June 26 0.15 6— 8 0.16 6-8 2.08 73 
July 7 0.19 8- 0.46 rs 5.05 113 
July 17 0.45 15-17 0.47 13-16 6.67 150 
July 28 0:23 8-11 0.53 20-23 9.23 175 
August 7 0.42 17-18 0.32 15 6.25 150 
August 18 0.34 12-18 0.31 14 5.68 135 
ADgust 98 fi tees 15-20 °.30 13-15 5.22 119 
September 8 0.26 II-13 0.55 23 9.32 218 
ober 1 0.38 13-19 OSB oh Ie a as eee 
November 1 ©. 26 1I-13 ©.49 20-22 9.26 212 
more trees to the same inquiry, and his investigations are of greater 
interest because he worked on white pine. Table J indicates his 
results on the three different specimens mentioned previously, and 
in each case fluctuations in growth are marked. The work of 
BucxHourt (2) serves to accentuate the same point. He made bark 
* measurements on a white pine and a larch which extended over 4 
