(see column headings) of the same series. 
TABLE V* 
. ’ iffering in hydrogen ion concentration at the two ends 
arg 3 : tered and selected by several species of fish. The fishes were confined in a long narrow tank differing in bh; " i in di : 
ordinarily they dia eS eerie ieativa Leietlt of tio! ae but moved back aaa forth, turning at definite points, and finally coming to rest. These turning and resting points differed in different experiments 
The upper figures of each couplet show the pH range within which the fishes came to rest; the lower figures of each couplet give the mean points of turning 
back when headed toward higher or lower pH, and the mean columns give the average pH content at the resting points selected. The third column from the right shows for all experiments the mean 
pH of the selections made. 
nomenclature after Forbes and Richardson.) 
The second column from the right gives merely the maximum and minimum of the upper figures of the couplets opposite. Aerated water was deep well-water aerated. (Species 
] Distilled water |y;.44 | 
i yi i Distilled water one HCl and cad- | 
Aerated water | Aerated water | Boiled watel pallediwater Rain-water Na,CO, | Dist Nied water mium and ae Hxtrenes SSE 
Number of experiments and H,SQ, HCl Na.CO, Na,CO, co, HCl | eas jsodium chlorides|"}57 1. | renthesis 
species used | | Fatal | Summary 
Mean | |Mean | |Mean| |Mean | |Mean |Mean | | Mean | |Mean | | | 
oe cone i ae ele were ewe (eee |e So | 
(15) 7.8-7.0 | TeO=TO|\0 wall asietsicteteters i}  Neooduacabal Sens |ponneooeollt- . icctadccuoc oe Winpocnooned (ee (ooooeooon i Eee a : 
i Play sen eae 7.4 | a27e2 | |e a ILO l. | fale ed ieyetare [Heath in § | Sree | 1.2 | -%.9-7.0)| 726 (7.2) 6.8 
Lepomis humillis ....... 7 48 i ligeyvaegueillt crane llegeeeet A on eee 7.6-6.9 7.3-6.8 |Kewe Sete a | omerene | 
i | | | | | 
1 | Taal . | | | | 
(12) | 7.6-7.1 NBS TEGY tee oa | SS, ceo Pme || Meetieantaetn eSpeterion Tew apecc ce ie Grill) oo soca Ae ah ete at 
Micropterus salmoides ...... 7.2 (CES | el Weep fe yak FE cele ga fic ("| eetaeewal | Roce) 7.3] 7.87.1] 7. E a 
ae? 7.8 EEA | ime enor Br la eel Ma Non costes 7.5-6.9 T9280) ans eee cece 
| | ! = Na ! am 
7 7 | | 1 
(15 8.0-6.9 7.1-6.6 | etatateceafsrelera 8.2-6.8 Wadochouce = |icbuatcocad| © | Iloacriaccnion | 
Micropterus dolomieu........ 7.2 Lion | 8.9 (hee {fC 3) | Mee MS Hiazcicies feed eee et Nasosas 7.4) 8.26.6] 8.2 (7.4) 6.6 
eS oie | meal leis ae stati: | 8.1-7.1 | 7.6-6.6 | 7.0 7.8-6.8 Samarte brie we I Harerctetaee | ; 
| | | 
an 7.87.1 7.8-6.8 TaTeT ae |e al|oee  e | eee [eat all Dene i | ec | 5 ae E 
Ambloplites rupestris ........ 7.4 ss ae 7.5 rel || Mea <a ae | 1 cel | 7 heed |) ae! 7.4| 7.8-6.8] 8.0 (7.3) 65 
7.3-7.2 7.5-7.4 | 7.0 | 8.0-6.5 eraereretateperts ene lasconoe i eS ash) = SIR cari sane | 
| | 
(12) 7.37.1 ace TES lle Mall ate aac ceN| a | teen) cael reer eee [eet Ie alate ark is | eee | 
Abramis crysoleucas......... 7.2 z TCH Se Ait Se: [eS fated (See | [abies aeons | Poneeae 8.2 7.1 j 7.4] 8.2-7.1] 8.3 (7.5) 6.3 
7.2-6.8 | OSS) | eecoeonnee \ss5eqbonKe| = elllberdoceon. | craic ter } 8.3-7.2 7.3-6.8 
aa) Pe eee) oko: | 7:3-1.2 {Sees bic Marusi | eles laeeerean le, lessen ser Palace 
Lepomis megalotis......... 130° alae recee PT |b SAR |e ot CPEs Cotes tl ee a a a ee Teoh lee 7.4| 7.8-7.0] 8.2 (7.5) 6.8 
Us| © WWicnosnqaan Tf Sa Olu | ean | avaieeteve ser | ACE a Re A Sci | 7.6-6.8 8.2-7.1 
be C5 6 eed Mr SNE | 
(6) atl Rea a pon | WIGHARe Sooo eK hae soncn Sete creel eae laa. | 
Lepomis cyanellus .......... (G7 Rn Karta on 7.6 RE eiceornie “es > | ne, RO ren alt eee Lisi icc 7.4| 7.7-7.1| 8.0 (7.4) 6.8 
Tet |rteeeeees d fagepdauacs 6.8 8.0-7.1 7.6-6.8 msisia einlersi 
(0) an | 3's lente ae lho tele t ll egal ee Pode l | | 
Notropis umbratilis .........'...... 1.5 Brey alread aa ie (ee at DRAG {EPS 2a aage 7.5 7.6 (7.5) 74 
Hoasaap aan : Octgy ooonn| anton BL (nce crare| ( ui 
| ; Doe Pilleiadaaaan : saat | me | eae | 
(10) T.1-7.5 [eee ore a fugniate\@¥axa)= 
Pimephales notatus ......... 7.5 i on ap poe | 8.2 mG On ane pec ee uae sss 7e| s.o7.5| s:4 (7-75) a1 
2 Heat Omsfist2at| amen cl lle ener 7.8-7.1 8.0-7.4 om see 
Notropis eoiie BOOP EBCR Ea | Haaniaian : Si Rea | Rem Lerten at ee Malo ee nt 
NOLTOPIS COTNUTUS ......-.66 DOr a0 Cy he res (oor yar, pt 7.4 Lie | ae cree CN a) gy (Cit err seeeel fw tte meee g.4 (1.7) i 
Hsanaae oH ante 8.4-7.1 8.3-7.0 big eta es boca 7.8 | 8.4-7.4 
(12) EEC abe, 4 aaa 8.47.6 a ee 
ORTauTRoTingiith: « ee is ies a ie fh eel oceans aa etasdeete vena Hoc rece Beas ono ie alleen: aeae (7.85) 7.3 
Reeaig ¥ aise sect ast Letaee| henge 7.9| 8.4-7.6] 8.4 (7. 
a 8.4 7.6 COLT | me RM coer we setae 
*The movements on which this table is based RyereieneonT _—————— oe 
of this series—and {no articles cited th 9 phed according to a method used b. Wells (’15 d by the aut! 7) 
ST ga coil ig Ta Wt Wuhan a eae ete et a PLATA AM SPN esentutl ot a DUD 
i 0, e average of a number of selections not reser. 8 : fh and ai pek and forth; in the second double column, 7.2 is evidently not the mean between 
ments were made in the type of water indicated, but the fishes cleast Reavy able; in thefifth and sixth double columns no range in sete tl sin stahecauneisah or two experl- 
as the fishes went to the end of the tank on the ae IMIR selected 7.1 as the resting point—as shown in the mean column. In ‘the CANES RTL umn, 
r : Li nellus, fifth double column, 
tinued to swim back and forth between the extremes Indicated. Inspeotiog Of the Brapha eee cgutG be recorded: in the seventh double column, no selection (a talented because the fishes con . 
—_—_—_Slllll 
of this table, 
