$4.00 per Year. 40 cts. per Copy. 
THE ^ 
timerican 
Naturalist 
A MONTHLY JOURNAL 
DEVOTED TO THE NATURAL SCIENCES 
IN THEIR WIDEST SENSE. 
AUGUST, 1889. No. 272 
CONTENTS. 
Tfu i:..iNivi 
..IXOK.HUT.RICV 
E D Cop/^Z 
>......„/.„.-.-henUMcohoIa.aPresen.t.e,or"" 
lil.IOK. o, G 
M.iNXr-.I.MU, 
rt'ct'of^Col' upon B"ctena-H.ctc4 S'^ce'S 
Tm .R.K , u 
V^c'^a.^'e,, 
n^Si-ne, . . 725 
,, I 01. 
M-,, . . 6S7 
Cix'cnterata, Worms , Crustacea , InsccN, F -' 7-3 
RNMIII^ in Cl MO 
/:-^dryolo^v-yiotes on the Development . t i 
:,':: 
....n.n... 
// //,,v./^/ 690 
p'lliina dtpressa S.iy — Developmcit of C/ i ^ n 
- «,0" ..r-Development of Sep>a ofu ^n U . 735 
I^Mbohscy — Ihe Psvchic Life of NLcio-Or-an.^m. 730 
",./p '"";;: ' 
\^/^;^,^ 
,n ''::z:i]::^::::S^^:^^:^7';i 
" 
\ I ' 
)U. } -. . 
K^'iio\.ng the (]eKitinoas Laver from the Batrach an 
^x. 
rT;;;!h"rnnrTitcLrot"'sM.tixAT'i'i8n^ 
' '\ / ' ' ~ ' 
" "'"'"' rx. 
Novc^.tie, Eng 7^ 
. ... ., 
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PHILADELPHIA: 
FERRIS BROS., PUBLISHERS 
