412 
MR. W. WEST AND PROF, G. S. WEST ON THE 
conspicuous. Cwlosphwrium very. common. 
Desmids not uncommon, but 
somewhat masked by abundance of Diatoms. 
very rare. 
Hotifers very few. Nauplii 
June 2nd, 1909. Temp. of water 56? F. (= 13:39 C.). Diatoms still domi- 
nant, but the Melosira-plankton has given place to a mixed plankton in 
which Tabellaria and Cyclotella are common. 
Increase in the Chlorophyee:e, 
Fig. 3. 
P | ЗЕР |OCT.| NOV |DEC.| JAN.| РЕВ. МАН. | АРВ. МАУ | JU. [ JY. [AUG] > 
ES 1908. 1909. i 
È | 15° |15:5?| 12-2°| 9-4? | 66? | 61°] c4? | 5° | 7.2° |13-3°|15-5°| 15° | È 
900°? к _— 4 PILIS 4 ` 
lc o T ` o! 
cec E a № ee |Ссс 
% Va /N o" ` 
- \ 
% А A 29% — 
: и / deem ' 
о "соро 
d оф 20929 cc 
ce ' ЖК q L^ A joo??? M | 
q oo? ГА 
q Pd 99° hn | 
P L 
R 3 И ni ni 
с 7 - E д ы a Pd c 
т T п: 2 ni „7 
^ с MN ° r 
N ° М о T "4 
№ am < $ u | 4 
N о Y EI М , 
r X / Sy ^ ШЧ Pd | А r 
А 1 M | 
X E Р 
NL ` / E 
rr >y n / "M rr 
/ MS -7 ГА 
BP РД 
/ `` i’ 
4 `` 4^ 
и BEN 2" | 
Ш ahr cae rrr 
STAURASTRUM PARADOXUM var MELOSIRA GRANULATA —— ——— —— 
CINGULUM ASTERIONELLA GRACILLIMA -.—--.-.- 
ST. LUNATUM var PLANCTONICUM -------- — C(LOSPHARIUM KÜTZINGIANUM өоооосә | 
Chart of the periodicity of five of the dominant constituents of the phyloplankton of 
Loch Lomond. The temperatures are in degrees Centigrade. 
including particularly fine specimens of 7etraspora lacustris. 
and 4-horned forms of Ceratium Hirundinella present. 
mostraea few. 
July 3rd, 1909. 
= 15°5° C.). 
which Desmids are much more numerous. 
Both 3-horned 
Rotifers few. Ento- 
Temp. of water 60° F. ( 
Mixed plankton in 
Complete disappearance of 
Melosira granulata and diminution of Asterionella. 
Increase in amount of 
