Transactions of the Academy of Science of 


St. Louis 


VOLUME XXVI = &%j 


TITLE PAGE AND INDEX 


August, 1928, 
to 


December, 1930 


Published Under Direction of the Council 


MissoOuR! BOTANICAL : 
GARDEN LIBRARY 


The Academy of Science of St. Louis 


LIST OF OFFICERS, 1930 


President A. F. SaTTERTHWAIT 
Vice-President LEsLIE DANA 
Recording Secretary A. S. LANcsporF 
Corresponding Secretary J. I. SHANNoN 
. Treasurer H. E. WrepEMANN 
Vi Librarian A. Kuntz 


it . J. LicHTer 


Curators Pink Rav 


Contents 


Page 
List of Officers iii 
Table of Contents iv 
Papers Published, August, 1928, to December, 1930: 
1. Charles E. Burt.—The Lizards of Kansas, Figs. 1-14.— 
Issued August, 1928 1 


2. Phil Rau and Nellie Rau—The Sex Attraction and 
Rhythmic Periodicity in Giant Saturniid Moths, Figs. 
1-2.—Issued August 15, 1929 


The Lizards of Kansas i 


THE LIZARDS OF KANSAS* 


CHARLES E, BURT 


Considerable work has been done on the lizards of 
Kansas, but it is scattered through various publications 
and manuscripts, and there is evident need for consoli- 
dation and further research. 

Three papers of primary interest to students of the 
herpetology of Kansas are those of Dr. F. W. Cragin 
(1881, 1884, and 1885), in which fifteen species of lizards 
were listed from the state. After making extensive col- 
lections during the summer of 1916, Mr. Victor H. Hous- 
holder prepared a thesis on the ‘‘Lizards and Turtles of 
Kansas,’’** and during the same year Dr. Edward H. 
Taylor completed a manuscript study of the ‘‘ Lizards of 
Kansas.’’** The author has recently written an article 
on ‘‘The Insect Food of Kansas Lizards, with Notes on 
Feeding Habits,’’ which is soon to appear in the recently 
established Journal of the Kansas Entomological So- 
ciety. Since full accounts are given in it, only summary 
sentences of the feeding habits of each species are pre- 
sented below. 

This present work was done at the Kansas State Ag- 
ricultural College during the years 1924 to 1927 with 
the following objectives in view: (1) The determination 
of the species of Kansas lizards, (2) The study of their 
taxonomy and variation, (3) The preparation of a key 
for their identification, (4) The preparation of an out- 
line of their distribution, with an analysis of the ecologi- 
eal factors which influence it, and (5) The presentation 
of a study of their habitats and habits. 


*Contribution No. 99 from the Department of —. of | the iS 


Kansas State Agricultural College. 
_ **These works were produced independently at the Kansa 


2 Trans. Acad. Sct. of St. Louis 


Over 1,700 specimens of Kansas lizards have been ex- 
amined by the writer during the progress of this study. 
These have been taken from 83 of the 105 counties of the 
state. Correspondence with many Kansas persons has 
yielded a large reward of specimens, and in addition the 
author has personally collected 275 Kansas lizards, in- 
cluding representatives of ten species and subspecies, 
many of which are from hitherto unworked areas. 

Good discussions of collecting and preserving methods, 
which have been found useful, are given by Stejneger 
(1891), Ruthven (1912), and Loding (1922). 

Reports of lizards, whether in the literature or not, 
have always been considered, but have not been accepted 
unless the specimens are in existence and the data of col- 
lection are thought to be without the possibility of error. 
The taxonomy used is after Stejneger and Barbour 
(1923) unless otherwise stated. The literature has been 
consulted extensively for descriptions of Kansas lizards, 
and these have been checked, and at times modified, with 
the aid of specimens. Thus, the descriptions presented 
in this paper are the summary of data taken directly 
from Kansas material. 

The study of variation has included the taking of 
measurements on all available specimens, and units of 
the metric system have been used for their expression. 
Important characteristics of the individual species, such 
as the interorbital scutellation of Crotaphytus collaris, 
or the barring on the sides of Holbrookia maculata ma- 
culata, have also been given considerable attention. 

This work was done at the suggestion and under the 
general direction of Dr. Minna E. Jewell of the Kansas 
State Agricultural College, to whom the writer wishes 
to express his grateful appreciation for many helpful 
suggestions and criticisms. Thanks are extended par- 


The Lizards of Kansas 3 


ticularly to Dr. Edward H. Taylor of Kansas University 
for the loan of his unpublished work on ‘‘The Lizards of 
Kansas’’ with the permission to use extracts from it* in 
the preparation of this paper, for complete data on the 
lizard collections of the Kansas University Biological 
Survey of the summer of 1926, and for his hearty co- 
operation throughout the progress of this study; and to 
Mr. Victor H. Housholder, formerly of Kansas Univer- 
sity, for the loan and permission to use extracts from his 
unpublished manuscript on ‘‘The Lizards and Turtles of 
Kansas’’*; also to Dr. Frank N. Blanchard of the Univer- 
sity of Michigan for the checking of identifications of 
lizards which were referred to him; to Dr. L. Stejneger 
and Miss Doris M. Cochran of the United States Na- 
tional Museum for some helpful identifications, opinions, 
and reports; and to Mrs. Helen T. Gaige of the Museum 
of Zoology of the University of Michigan for aid in the 
identification of certain specimens of Ewmeces. 

Through the courtesy of Mr. C. D. Bunker of the Kan- 
sas University Museum a large part of the data used in 
the preparation of this work were secured from the ex- 
cellent collection of over 1,000 specimens of Kansas liz- 
ards preserved there. Mr. Howard K. Gloyd has kindly 
loaned the lizard collection of Ottawa University, Mr. 
L. D. Wooster that of the Kansas State Teachers’ Col- 
lege of Hays, the Rev. Felix Nolte that of St. Benedict’s 
College, and Dean Emil O. Deere that of Bethany Col- 
lege. The United States National Museum has been very 
helpful in loaning specimens of the rarer species of 
lizards. 

The author wishes to express his appreciation to his 
wife, May Danheim Burt, with whom he has discussed 
much zaneh 96 this work, for assistance in the taking of data 


items that are quoted from these sources are indica a 
use ig ibe author’s name and the designation, “(Unpublished)”. 


4 Trans. Acad. Sct. of St. Lows 


on specimens of lizards which he examined at the Kansas 
State Agricultural College; and to his cousin, Mr. W. H. 
Burt, formerly of the Kansas University Museum, who 
kindly assisted in a similar way while the writer was 
studying the lizards preserved there. 

The writer feels very grateful to Dr. Robert K. Na- 
bours of the Kansas State Agricultural College for his 
continual encouragement and co-operation during the 
time occupied by this study, and also for furnishing 
facilities in making exchanges. 

A large number of persons have contributed specimens 
of lizards to Kansas museums, but the list is too large 
and incomplete to be reproduced here. There are a num- 
ber of persons who have been very kind in sending the 
writer both specimens and data, and to these he is ex- 
tremely grateful. Among these, aside from those who 
have already been mentioned, are F. F. Crevecoeur, H. J. 
Harnly, Ivan R. Burket, A. J. Cheatum, L. M. Clausen, 
Frank W. Jobes, H. H. Schwardt, Harry G. Walker, 
Stephen T. Egan, A. P. Williams, T. E. White, Leonard 
Montgomery, Gerald G. Grout, W. J. Robinson, Robert 
Kingman, William R. Thompson, ‘Kathlene Margaret 
Thompson, Verl Fink, Paul White, A. R. Miller, and 
Floyd Pauley. 


A Key to the Species of Lizards Definitely Reported from Kansas 


. Four legs present; lateral os a 
Legs absent: lateral fold present... 2. isos eo ee 
ida 


ae, sors saalec ventralis (Linné).p. 36 


~_ 


ee ee ee a ee? 


2. Femoral pores present or head with ogous spines... .. 3 
Femoral pores absent and head without spines....... Scincidae. 9 
3. Lateral scales tg abruptly smaller than sauces ventrals in 
MEEFOOS BOS i es guanidae. 4 
s 


Lateral es eth ruptly oe than ventrals; large ventrals in 
eight longitudinal vovavdetens ee eee 
Teiidae, Cnemidorphori sexlineatus (Linné).p. 38 
4. Body flattened and with many horny tubercules or spines; tail 
less than forty per cent of total length Phry. 
Body not noticeably flattened; horny tubercules and spines ab- 
sent; tail over forty per cent of total length 


a] 
Sg 
P 
a 


ee ee 


The Inzards of Kansas 


5. Two rows of marginal spines present _ SIDOR os oe aes 
P. sb ” Harlan). p. 27 
One row of marginal -sgirti BUOGEN ew sh eer aes bee es 
ouglassii ornatissimum (Girard).p. 32 
Ear opening present; upper labial scales not oblique and not 
VORTMAN 5 5k hin yh 6 Se ie y's a aes Onn eo eke E soe ex 
Ear opening absent; upper labial scales oblique and overlap- 
BS eb yas a EK ae Wo wo ee Fe aR eS WN anne Chena reuse 
lbrookia maculata maculata (Girard).p. 11 
7. Dorsal scales smooth; black sige PEORONC ire ee peek eee 
otaphytus collaris (Say). 
Dorsal scales — and seaversiog to a point eateentes 
pT ge EE at Ng eet s Meena anger ai gr erin Pry yee oe 
. Wavy dark eS cross wend present on sides and back........ 
S. undulatus nautaten Pen. Dp: 19 
Cross bars restricted; sea dark brown spots usually present 
on sides. 2... S. undulatus thayerii (Baird and Girard).p. 16 
. Lower eyelid with pens ene central part ; body bronze above, 
cylindrical; limbs minute..... Leiolopisma "laterale (Say).p. 45 
Lower oo, healy boy not Sota bly cylindrical; limbs of 
TEGO ENO a os oi chs i ik ons ok eee eb aves Eumeces 
; eons ne rows extending parallel to dorsal rows........... 
Lateral scale rows extending diagonally from seitiodatoen) 
to dorso-lateral surface..Eumeces obsoletus (Baird and Girard). 
p. 58 


i) 


© 


re 
i] 


11. Back with seven or more narrow re stripes, and nine or more 

BP anes oe a es E, ego cad gectamcaa p. 56 

Back with fewer light stripes at Gark Bands. ic. ss ki eh das 

12. Body blackish, with five prominent light at the center one 

forking on the head...... E. res sciatus (Linné). Young to adult 

in primary StRRO Gt CIOVOIOPMCNt orice ea tee eben es p. 51 

Body with four prominent eight lines, four faint lines, or none 

13. Body with two prominent light lines and two broad dark bands 

OR CACR AINE oo in vs eas oe i os E. septentrionalis (Baird).p. 63 

Body with two light lines on each side: prominent or not; foe 
ne a broad, dark band of solid color; or with lin 

14, ax absent; cheeks reddish or brown; general coloration light. 
E. Aeipaiigd (Linné). Aged adult in tertiary or last stage o * de- 
Ue ee oe a ob hea ki cee ease 
ines 4 ctegbak: general coloration usually somewhat picker: 

- Scales of wide mid-dorsal band with perceptible light and dar “ 
areas, not unicolor........ né se iatus (Linné). Adult in inter- 
mediate stage of development... 2.2.6.6. 0.sseeesceevns p. 51 
Scales of wide mid-dorsal en ai oes light and dark areas, 
but unicolor; the band black to brown.................-54+: 

~. aairacines (Baird).p. 49 


A LIST OF THE SPECIES OF LIZARDS DEFINITELY KNOWN 
INHABIT THE STATE OF KANSAS 


— 
on 


Crotaphytus collaris (Say)* 
species are pb will be Sivedtelint his forthcoming 


Museum of Zoology of the University of Michigan. 


a 
ee) 


14 


_ 
or 


TO 


6 Trans. Acad. Sci. of St. Louis 


Collared Lizard, Mountain Boomer, Black Shouldered 
Lizard, Bull Lizard, Gray Nellie. 

Description—Head large and sub-triangular; body 
thick; tail long and tapering to a point; supraocular 
scales usually small, excepting for a few enlarged ones 
near the center; supraocular area rising above interorbi- 
tal area; ear opening large and prominent, with an an- 
terior denticulation; tympanum exposed; one gular 
fold well developed, three sometimes present; labials not 
oblique or overlapping; lower series larger than upper 
series. 

All body seales finely granular; scales of back and 
sides about equal in size; ventrals larger; femoral pores 
distinct, well developed, with white, brown, or black cen- 
ters, enlarged in males, small in females; number, from 
fourteen to twenty-five; back part of mouth cavity black; 
males with one or more pairs of enlarged post-anal 
plates; females usually with even transverse scutellation 
behind anus. 

Coloration varies; colors well defined in nature, but 
fade to dull shades in captive specimens; coloration 
lighter at high temperatures and darker at lowered tem- 
peratures*; ventral color varies from a medium brown- 
ish to an immaculate white, through various shades of 
greens, grays, and blues; Kansas specimens without 
black or brown loin patches; dorsal ground color varies 
from blackish gray to light bluish gray; usually with 
pale dots which have no definite order of arrangement; 
light colored bars extending transversely across the dor- 
sal surface in certain specimens; back often with scat- 
tered flecks of brown, orange or reddish; lower jaws 


*Franklin (1913) found that “During the cooler hours of the day 
these liz izards were a dark dirty gray, but when the air was warm an 
~ lizards became more peri the color changed to a bright emerald 


The Lizards of Kansas 7 


occasionally with a pattern of alternate white and gray 
transverse bars, giving a ‘‘tiger design’’; upper head 
scales usually green or brownish olive with the colora- 
tion becoming more intense as the median line is ap- 
proached. 

Double black collar on shoulders, not extending ven- 
trally in Kansas specimens; both bars of collar usually 
broken dorsally; back and tail of same general colora- 
tion; tail much more blotched and sometimes with ringed 
appearance; color duller in young than in adults; large 
males sometimes with highly colored gular region of 
orange or yellow and much of the rest of the body blue 
or green; other males and always females, duller. 

During the fall of 1925 the writer collected, and ob- 
served the coloration upon, over forty young specimens, 
all of which showed the dull coloration characteristic of 
the female. The colors of all forms are deeper after the 
skin is shed, and those of the adults, also, at the spring of 
the year during the mating season. 

In 275 specimens from Kansas the number and ar- 
rangement of the scales between the orbital areas has 
been found to be as follows: specimens with two distinct 
rows, 28 or 10.2 per cent; specimens with two of these 
paired scales fused to one single scute, 115 or 41.9 per- 
cent; specimens with four fused to two singles, 121 or 
44.0 per cent; specimens with six fused to three singles, 
10 or 3.6 per cent; and specimens with eight fused to 
four singles, 1 or 0.3 per cent. This indicates that the 
interorbital scutellation of Kansas individuals presents, 
essentially, a condition of two rows, excepting for a few 
fused scales which make a single row for a short dis- 
tance. 

A summary of the study of 300 Kansas specimens is 
given below. Measurements are given in millimeters, 


8 Trans. Acad. Sct. of St. Lows 


thus: ‘‘Minimum—maximum (mode)’’ m this and m all 
of the following summaries. Length of body, 38-111 (81- 
90); length of tail, 57-210 (151-165) ; total length 98-309 
(221-240) ; width of head, 9-29 (18-20) ; length of tail as 
percentage of body length, 57.1-72.5 (64.1-66); width of 
head as percentage of body length, 20.0-30.0 (22.1-24). 

Ellis and Henderson (1913) have listed this species as 
reaching the total length of 380 millimeters, which is 
greatly in excess of the length of the largest Kansas 
specimen examined by the writer. 

Habitat and Habits——Cope (1866) gave the habitat of 
this species as, ‘‘Sand, logs, among brush, etc.’’—Stej- 
neger (1893) found it to be ‘‘Evidently an inland desert 
form of the Upper Sonoran life zone.’’—Van Denburgh 
(1897) found that this reptile is a lizard of the desert, 
but that it does not seem to live on its lower levels, pre- 
ferring the more mountainous regions between the alti- 
tudes of 4,500 and 6,500 feet. Taylor (1912) wrote of 
Humboldt County, Nevada, specimens, stating that 
‘‘Hleven were taken near Big Creek Ranch at altitudes 
ranging from 4,800 to 5,400 feet. We look in vain for 
this species in the open desert and on certain of the lower 
- slopes of the mountains. All but one of the specimens 
were collected on the top of a steep sided rocky ridge.’’ 
Richardson (1915) stated that ‘‘The lizard was found 
only on hillsides amid deposits of tufa and outcroppings 
of voleanie rock at an elevation of 4,500 feet.’? In Kan- 
sas, collared lizards have been collected only between the 
altitudes of 800 and 2,200 feet, though there are points in 
western Kansas with an altitude of 4,000 feet. Bentley 
(1919) wrote that specimens were usually found in Nye 
County, Nevada, ‘‘On the large, flat rocks of a steep hill- 
side.’’ 

Dr. Ivan R. Burket of Ashland, Clark County, Kansas, 


The Inzards of Kansas 9 


wrote in May, 1925, that ‘‘ A specimen ran into a hole on 
our golf course, and to obtain it, I had to dig it from its 
shelter.’’ Prof. L. D. Wooster of Hays has stated that 
he found collared lizards along the rocky hillsides which 
border the Smoky Hill River in Ellsworth County. The 
writer has found this species to be almost always near 
rocky ledges, especially along the brows of hills. The 
flat, loose-lying, limestone rocks of the rolling prairie 
country are very characteristic of its habitat. On warm 
days of the spring, summer, and fall, this reptile may 
often be found sunning itself on a rock or boulder or 
going about in search of food. The winter is spent in 
hibernation under the rocky ledges. 

A variety of Kansas habitats are known for this spe- 
cies. In Riley County it has often been found under hill- 
side rocks, around rock fences, and in rock quarries. 
Also, several specimens have been observed along the 
banks of the wooded Wildcat stream, west of Manhat- 
tan, where two of these little animals were found very 
close to water. Along a low, flat, barren, rocky, sandy 
ledge, which was exposed to the hot May sun of Rush 
County, a specimen was taken. Though the species is 
more frequently found near wooded slopes, this particu- 
lar specimen was far from trees. 

Very few notes have appeared which deal with the 
breeding habits of the collared lizard. Hallowell (1856) 
dissected a large female and found eight large eggs. 
Strecker (1910) stated that ‘‘The eggs range in number 
from four to twenty-four, and are deposited in loose 
sand to a depth of four or five inehes.’’ Ditmars (1915) 
recorded the deposition of a total of twenty-one eggs by 
a large female. Taylor (unpublished) found the egg 
number to be from five to seven, stating that ‘“‘They are 
deposited at the end of shallow tunnels immediately ~ ae 


10 Trans. Acad. Sci. of St. Louis 


low large, flat rocks. The passageway near the eggs is 
then stopped up by the female with closely packed earth, 
and the young must dig their way out after hatching.’’ 
A Riley County specimen which the writer opened con- 
tained seven eggs. Another which was transported to 
Cheboygan County, Michigan, early in the summer of 
1927 laid two eggs on June 26, one on July 1, two more on 
July 2, and finally four others on July 4, a total of nine 
eggs in nine days. 

The food of Crotaphytus collaris consists, chiefly, of 
the larger insects, particularly grasshoppers and 
crickets. 

Distribution im Kansas—Kansas_ specimens that 
might be identified as the “‘bailey:’’ type have always 
been found in co-extensive distribution with the ‘‘col- 
laris’’ type. The collared lizard has been taken in the 
eastern two-thirds of the state only. It has generally 
been found about rocky formations which cover a con- 
siderable area, and has usually been absent from small 
outcroppings of rock. This, together with the fact that 
it has not been collected in large cultivated areas, such as 
are found in Rice, Barton and Brown counties, would 
tend to indicate that it is not a species highly resistant to 
the encroachments of man upon nature, and as agricul- 
tural methods become more intensive and more ground 
is tilled in Kansas the area of its distribution will prob- 
ably be constantly decreased. Although the collared 
lizard is said, by various writers, to be a desert form, 
the author has not found it in the drier situations of 
Kansas, even though rocks were there in abundance. It 
is usually found where there is considerable moisture, 
typically at the upper edge or above the woods which are 
found near streams, and the dry condition which is pre- 
sented by the climatic cycle of western Kansas may help 


The Lizards of Kansas 11 


to restrict its range from that area. Neither the large 
chalk beds of Trego and Gove counties, nor the great 
sandy areas of the state, as those in Reno and Stafford 
counties, have yielded specimens of the collared lizard. 
Northeastern Kansas apparently does not present favor- 
able geological conditions for its dispersal, and too, it is 


Fig. 1. Distribution of C. collaris in Kansas as indicated by the county 
reports. 


an area characterized by a dense agricultural popula- 
tion. 
Holbrookia maculata maculata. (Girard). 
Holbrook’s Sand Swift, Spotted Lizard, 
Cactus Lizard. 


Description—Head broad and short, convex; widest 
in orbital region; muzzle broad and rounded; neck thick; 
body rather stout and depressed with tail tapering rap- 
idly to a point; tail thick at its base; ear opening ab- 
sent; six oblique and imbricate upper labials; strong 
superciliary ridge above eye; supraocular region not 
elevated above superciliary ridge; head scales moder- 
ately tuberculate; dorsal scales small, finely granular, 


12 Trans. Acad. Sci. of St. Lows 


and somewhat tuberculate in large specimens; ventrals 
decidedly larger; enlarged post-anal plates present in 
males only. 

Coloration not highly variable; ventral parts immacu- 
late white, with or without a ‘‘tiger design’’ of slate col- 
ored bars on the chin; dorsal ground color ashy gray, 
with two rows of dark blotches extending from the re- 
gion posterior to the head to well upon the tail, varying 
in series, anterior to posterior, from ten to fourteen in 
number; median line distinct and free from blotches; a 
row of lateral blotches on each side, usually not sharply 
defined, but distinctly visible; subcaudal black spots 
never present; from two to four black latero-ventral bars 
on each side of abdomen; lateral aspect of the belly 
sometimes bluish; otherwise, the ground color of the 
sides varies from light yellowish through different 
shades of orange to dull reddish. 

By the examination of 148 specimens of H. maculata 
maculata from Kansas, it was found that the black bars 
on the right side numbered from two to four units, as 
follows: with two bars, 104 specimens; with three bars, 
38 specimens; with four bars, six specimens. There is 
sometimes the same number of bars on each side of this 
lizard, two being the most common, but frequently there 
is a variation, three on one side and two on the other oc- 
curring most often. Schmidt (1922) found in a series of 
nineteen females from Colorado that ten had two spots 
on each side, four had two spots on one side and three on 
the other, five had three spots on each side, and one had 
three on one side and four on the other. 

In order to study the variation in size and proportion 
of this lizard 175 Kansas specimens have been measured. 
Unfortunately the writer failed to sex a large proportion 
of them, so sexual dimorphism cannot be fully treated. 


The Inzards of Kansas 13 


A summary of the data follows. Length of body, 20-61 
(45-60) ; length of tail, 17-76 (36-45) ; total length, 38-132 
(91-100) ; width of head, 4.5-11 (8-9); length of tail as 
percentage of total length, 39.9-58.3 (44-46); width of 
head as percentage of body length, 13.0-22.9 (18-20). 

In his key to the species of Holbrookia, Schmidt (1921, 
1922) separated H. maculata maculata from other liz- 
ards of the genus by the character, ‘‘Tail shorter than 
body in the female, usually also in the male.’’ To test 
this distinction, 32 specimens, males and females in 
equal numbers, were selected and measured. The results, 
expressed in terms of length of tail as percentage of 
total length, are as follows: 

Males: Range, 44.0 to 58.3 per cent; average, 49.0 per 
cent. 

Females: Range, 41.0 to 49.3 per cent; average, 45.0 
per cent. 

This indicates that Schmidt’s distinction holds uni- 
versally for the females, but does not do so for the males. 
Twenty-nine or 18.5 per cent of the 175 specimens cited 
in the measurement table above had a tail length of over 
50.0 per cent. Granting that they are all males, the prob- 
ability of error (as indicated by this series) in the iden- 
tification of a male of H. maculata maculata by Schmidt’s 
key would be approximately 37.0 per cent. 

All of the measurement figures given by other writers 
for this species fall, so far as known, within the ranges 
designated in this work. 

There has been considerable question as to the possible 
presence of H. maculata lacerata in Kansas. Cope (1900, 
p- 293) reported it from Neosho Falls, Woodson County, 
on the basis of three specimens (No. 4693) in the collec- 
tion of the United States National Museum. The exam- 
ination of over 200 specimens of H. maculata from Kan- 


14 Trans. Acad. Sci. of St. Lowis 


sas has failed to reveal anything but the typical H. macu- 
lata maculata. No specimens have been found with sub- 
caudal black spots, or without latero-ventral black bars. 
The specimens identified by Cope as H. maculata lacer- 
ata had previously been referred by Dr. Stejneger to H. 
maculata maculata, as stated by Schmidt (1922). Dr. 
Stejneger wrote to Mr. Housholder of Kansas Univer- 
sity in 1916, stating that ‘‘So far as coloration of the 
upper parts is concerned, H. maculata lacerata is closely 
approached by three specimens from Neosho Falls, Kan- 
sas, and in regard to the lateral spots, it may be stated 
that they are present.’? Housholder (unpublished) bor- 
rowed these specimens from the United States National 
Museum and after examining them wrote that, ‘‘There 
are two distinct dark blue spots on the sides of each of 
the specimens, but no evidence of the transverse spots on 
the inferior surface of the tail; therefore, considering 
these facts, Dr. Stejneger’s statement, and Bailey’s 
(1905) restriction of this subspecies to Texas, I consider 
the identification of Cope’s three Neosho Falls specimens 
as very doubtful, and the occurrence of H. maculata la- 
cerata in the state as very unlikely.’’ In view of the ex- 
isting data the writer feels little hesitancy in witholding 
the subspecies, H. maculata lacerata, from the Kansas 
faunal list. 

Habitat and Habits—Little has been written about the 
natural habitat of this small lizard. Taylor (unpub- 
lished) found a great many specimens in the chalk eoun- 
try of western Kansas. MHousholder (unpublished) 
found them rarely under rocks and other objects, unless 
they were driven there for safety. He has stated that 
‘*A specimen was captured while attempting to swim a 
riffle in a small river. It is very probable that the lizard 
was driven from the gravel at my approach, and had 
taken to the water as a means of escape.”’ 


The Lizards of Kansas 15 


The writer has usually found this lizard in the open 
sun in places with sparse vegetation. It lives in small 
holes in the sand or gravel and stays there during the 
night, and on cold and cloudy days. When disturbed by 
a collector it often escapes by running swiftly into plum 
thickets, which are numerous where it occurs in abun- 
dance. 

Little attention has been given to the breeding habits 
of these sand swifts. Taylor (unpublished) found the 
egg number to be from six to eight. A specimen which 
was collected in Osborne County, late in July, 1926, con- 
tained seven eggs which measured about twelve by eigh- 
teen millimeters in size. 

This species is a voracious feeder upon small insects, 
particularly small grasshoppers and bugs. 

Distribution in Kansas.—The range of the spotted liz- 
ard in Kansas extends approximately over the western 
two thirds of the state. Although listed from Woodson, 
Wilson, Elk, and Butler counties, it is very uncommon 
in the southeastern part of the state and occurs there 
only in sandy areas. In McPherson County it was found 
on ‘‘T'win Mounds,’’ which are two large sand and rock 
covered hills that rise above the prairie. The distribution 
of the lizard in that vicinity was very local. Its power to 
live in a small favorable area might help to explain its 
widespread distribution over isolated sandy places like 
those of southeastern Kansas mentioned above. In the 
sand dune region surrounding the salt marshes of Staf- 
ford County this subspecies is present in large numbers, 
and may be seen on warm days of the spring or summer 
running swiftly across open sandy places which are in- 
terspersed with small patches of vegetation. The chalk 
beds of Trego and Gove counties have yielded many 
specimens. In Ottawa County the writer found this : 


16 Trans. Acad. Sct. of St. Louis 


lizard in the center of a sandy wheat field. Holbrookia 
maculata maculata, and specimens of Cnemidophorus 
sexlineatus and Sceloporus undulatus thayerit, are prac- 
tically the only lacertilian inhabitants of many of the 
counties of the western half of the state, and are the only 
specimens that have been taken from much of that area, 
including Trego, Gove and Stafford counties. 


B 
Cheyenne Nora | phitips | Smith | Jewey | "*PP%H0 [vrashington| Marshall | Nemaha} ” Powe! 


Fig. 2. Distribution of H. maculata maculata in Kansas as indicated 
by the county reports. 


Sceloporus undulatus thayeru. (Baird and Girard). 
Yellow-banded Swift, Striped Spiny Swift, Thayer’s 
Alligator Lizard. 

Sceloporus thayerii.—Baird and Girard, 1852, Proce. 
Acad, Nat. Sci. Philadelphia, 6:127 (type locality, ‘‘In- 
dianola, on the Gulf of Mexico, San Antonio, Texas, El 
Paso del Norte, and as far westward as the Province of 
Sonora’’). 

Sceloporus consobrinus—Baird and Girard, 1853, 
Rept. Marcy’s Expl. Red River, p. 237. 

Sceloporus undulatus thayerti—Cope, 1875, Bull. U. 
S. Nat. Mus., 1:49. 


The Lizards of Kansas 17 


Sceloporus undulatus consobrinus.—Cope, 1900, Ann. 
Rept. U. S. Nat. Mus, for 1898, p. 377. 

Sceloporus thayerii.—Cope, 1900, Ann. Rept. U. S. 
Nat. Mus. for 1898, p. 385. 

Sceloporus consobrinus consobrinus.—Stejneger and 
Barbour, 1923, Check List N. Amer. Amph. Rept., p. 54. 

Jones (1926) has shown that S. thayerii is the proper 
name for S. consobrinus, but has not made clear just 
what should be done about the subspecific classification 
of the lizard. 

Description—Head somewhat narrowed and de- 
pressed; superciliary ridge slight; tympanum exposed; 
a well-marked fold of skin on each side of neck, making 
a characteristic groove; gular region without a fold; 
body moderately slender; tail tapering gradually to a 
point; head plates large and smooth; supraoculars 
bounded on each side by small scales; occipital plate 
large and very prominent; dorsal scales very strongly 
keeled and with strong posterior spines; scales of lower 
sides and abdomen smooth and without keels; femoral 
pores present; enlarged post-anal plates in males only. 

Coloration varied; dorsal ground color light to dark 
brown; abdomen whitish; sides often brilliant blue; usu- 
ally with two well defined stripes of clear yellow on each 
side; a series of dark brown lateral spots, which never 
connect to form undulating lines, usually present above 
and below the upper longitudinal stripes. 

In order to study the variation in size and proportion 
of this lizard 108 Kansas specimens were measured. The 
data are as follows: Length of body, 21-62 (49-56); 
length of tail, 24-81 (61-70); total length, 45-140 (111- 
120) ; width of head, 5-12 (8-9) ; length of tail as percent- 
age of total length, 48.3-61.1 (56-58); width of -head as 
percentage of body length, 13.5-24.1 (16-18). — 


18 : Trans. Acad. Sci. of St. Lows 


Ellis and Henderson (1913) gave the maximum total 
length as 203 mm., a figure decidedly above the maximum 
found in Kansas specimens. Taylor (unpublished) listed 
the following measurements: total length 160 mm., body 
length 68 mm., and tail length 92 mm. These figures 
were obtained from a much larger Kansas specimen than 
the writer has been able to examine. 


Habitat and Habits—Regarding the habitat of this 
subspecies, Cope (1880) wrote that, ‘‘It is found on the 
ground, but always takes refuge in the trees, running on 
and around limbs with great agility.”’ Ruthven (1907), 
however, found it to be ‘‘Principally a ground form; in 
the mountains being found about rocks, and in the plains, 
about the foot of bushes.’’ Strecker (1908) wrote that 
most of his specimens were collected on rail fences and 
around old logs in the woods. Van Denburgh (1922) 
stated that ‘‘This species is usually found on the ground 
and retreats to holes in the earth, banks, or spaces under 
or between stones, and occasionally it resorts to trees.’’ 
Over (1923) found it living in the sandhills of Washing- 
ton County, South Dakota. Taylor (unpublished) quoted 
farmers in western Kansas as saying that ‘‘Large num- 
bers of these lizards are found in wheat fields, especially 
under grain shocks.’’ Taylor also stated that he had col- 
lected as many as five specimens under one shock of 
wheat. 


Yellow-banded swifts are usually abundant where 
they occur. Rock formations, especially of sandstone, 
often harbor them, though many have been taken from 
sandy regions where there are no rocks. During the 
month of May, a number of specimens were found about 
the ‘‘Twin Mounds’? near Lindsborg, McPherson 
County. Some were taken from a sandy pathway ex- 
posed to the full glare of the sun, and others were re- 


The Lizards of Kansas 19 


moved from the sides of large boulders, which they 
scaled with ease. A few of these swifts were taken from 
prairie grass near a rock ledge in Ellsworth County, and 
several persons have found the chalk beds of Trego and 
Gove counties to shelter many specimens. The sand 
dunes of Stafford County, though probably less favor- 
able to this subspecies than to Holbrookia maculata ma- 
culata, have their quota of both species. All yellow- 
banded swifts taken there were removed from the sur- 
face of the ground, with the exception of five, which were 
captured upon the sides of a farm shed which was coy- 
ered with sanded tar paper. 

The yellow-banded swift feeds upon a large variety of 
small insects, particularly beetles, ants and grasshop- 

ers. 
Little attention has been given to the study of the life 
history of this lizard. Shufeldt (1885) found seven eggs 
in the uterus of one female. Strecker (1910) reported 
two females with eggs, one having six, the other eight. 
Taylor (unpublished) stated that ‘‘Females taken in 
July had not yet deposited their eggs. One very large 
specimen was found to contain fifteen.’? The writer has 
found seven Kansas females to contain lots of seven, 
seven, seven, eight, nine, nine, and eleven eggs, respec- 
tively, giving an average of eight eggs per female. On 
June 12, 1926, a specimen laid six white eggs which 
measured six by ten millimeters in size. 

Distribution in Kansas—S. undulatus thayerii is gen- 
erally distributed over central and western Kansas. 
Further collecting in the counties in that area will very 
probably add to the county distribution list indicated by 
the following map. 

Sceloporus undulatus undulatus. (Latreille). 
Pine Lizard, Fence Lizard, Tree Lizard, Black Lizard, — 


20 Trans. Acad. Sci. of St. Louis 


Brown Scorpion, Eastern Spiny Swift, Pine Tree Liz- 
ard, Alligator Lizard, Scaly Lizard. 

Stellio undulatus—Latreille, 1802, Hist. Nat. Rept. 
2:40 (type locality, ‘‘Les grands bois de la Caroline’’). 

Sceloporus undulatus——Wiegmann, 1828, Isis, p. 369. 

Sceloporus undulatus.—Stejneger and Barbour, 1923, 
Check List N. Amer. Amph. Rept., p. 59. 

Sceloporus undulatus undulatus—Cope, 1900, Ann. 
Rept. U. S. Nat. Mus. for 1898, p. 370. 

Description—Head large and somewhat depressed; 
body moderately stout; ear opening present; no gular 


8 
Philips | Smitn | Jewen | "PIC lwasmngton| Marshall | Nemahs| ~—  [Po™Pbes 
SS 


Cloud Avclison 
Jackso: 
Cay | Ruey Pottawstamie| “kon pee ~ 


BIEL ELE ell 


‘3 


catnip el th ae IT LE Ne TRE Ninh eminem SNR et 


U 


a ali eek BR Da etn il a tne td ae ee Cems a | ha pe ee ae gt oe ae 


Fig. 3. Distribution of S. undulatus thayerii in Kansas as indicated 
by the county reports. 


fold; neck groove conspicuous; tail moderately long; 
head plates large; occipital plate very conspicuous; su- 
praoculars of medium size, bounded by a few small scales 
on each side; dorsal scales keeled and with strong pos- 
terior spines; abdominal and lateral scales smooth, with 
weak posterior spines; femoral pores present; enlarged 
post-anal plates in males only. 

Dorsal color olivaceous or brown; sides often with at 


The Lizards of Kansas 21 


least traces of two whitish or yellowish longitudinal 
stripes, which may be distinct enough in some specimens 
to intergrade with the condition usually found in S. wn- 
dulatus thayerii; sides, also, with wavy, dark brown 
eross bars, approaching each other or overlapping on 
the back, and leaving not more than a narrow mid-dorsal 
band of solid ground color; ventral parts green, slate, 
olivaceous, or white; sides of abdomen and throat often 
blue; a diffuse streaking of blackish flecks present on the 
ventral surface. 

The study of variation in the size and proportion of 
this species was made from 55 Kansas and Arkansas 
specimens. The data follow: Length of body, 34-67 (41- 
90); length of tail, 45-98 (51-60); total length, 80-162 
(91-105) ; width of head, 7-14 (8-9) ; length of tail as per- 
centage of total length, 49.5-61.4 (58-60); width of head 
as percentage of body length, 17.8-24.0 (18-20). 

It is to be noted that the head widths of the two Kan- 
sas subspecies of S. undulatus have the same mode, and 
that the range of variation in most other proportions is 
nearly the same. Housholder (unpublished) attributed 
a wider head to 9. wndulatus undulatus than to S. undu- 
latus thayerit. To test this distinction, twelve pairs of 
specimens, which measured the same in total length, 
were selected at random from the writer’s data tables 
for each subspecies. The summary of the comparative 
head widths follows. 

S. undulatus undulatus: Range, 8.0-10.5 mm. Average 
9.017 mm. 

S. undulatus thayeru: Range, 7.5-11.0 mm. Average 
9.083 mm. 

The difference in the head width of the two forms, as 
indicated by this comparison, is too small to be consid- 
ered significant. However, the following summary, 


22 Trans. Acad. Sci. of St. Louis 


which was obtained from the examination of the 55 speci- 
mens of S. undulatus undulatus and the 108 specimens of 
S. undulatus thayerii, does indicate a difference in the 
proportions of the two lizards. 


undulatus thayeru 
Mode of width of head as per- 
centage of body length_- 18- 20 16- 18 
Mode of total length in mm. 91-105 111-120 


It is apparent that the series of S. undulatus undulatus 
are on the average about 18 mm. shorter than the series 
of S. undulatus thayerii, and that the width of head as 
percentage of body length in the former lizard averages 
two millimeters greater than in the latter form. Hence, 
these data indicate a wider head in proportion to the 
body length for the subspecies S. undulatus wndulatus, 
and conversely, a more slender body when compared 
with the width of head for the subspecies, 8. undulatus 
thayerit. 

So far as known, the measurements given by other 
writers for the pine lizard agree with those of the author. 

Habitat and Habits—Considerable mention has been 
given the pine lizard in the literature, because its wide- 
spread distribution has enabled many American natural- 
ists to study it. De Kay (1842) stated that ‘‘It inhabits 
sandy and rocky situations.’’ Holbrook (1842) wrote 
that ‘‘It is chiefly found in the pine forests of our coun- 
try, being often under the bark of decaying trees. It 
chooses old fences as a basking place. It is exceedingly 
rapid in its motions, climbing with great facility to the 
tops of trees, and hence it is not taken alive without 
great difficulty.’’? Smith (1882) wrote that ‘‘It prefers 
sandy and rocky soils, especially regions of pine forests, 
and apparently does not occur in wet places.’? Hay 
(1892) stated that ‘‘It is not disposed to seek safety by 


The Inzards of Kansas 23 


flight, but by concealment. It will dive behind a trunk of 
a tree and while trying to dodge one hand may be caught 
by the other.’’ Rhoads (1895) found it distributed all 
over the state of Tennessee below the elevation of 3,000 
feet. Hay (1902) wrote that it was ‘‘ Very common in the 
higher and drier situations. It is often seen there dur- 
ing the warm days of summer, basking in the sunshine 
of some exposed rail fence or log.’? Hahn (1908) ob- 
served that ‘‘They are very abundant in the woods and 
along fences.’’ Allard (1909) stated that ‘‘It is a very 
common lizard familiar to nearly everyone throughout 
the south. It is abundant in all wooded upland situa- 
tions, and loves to bask in the hot sun, as it stretches out 
lazily at full length on a fence rail or rock. When dis- 
turbed it runs with great agility, usually up the nearest 
tree. On the tree trunk it usually moves so as to keep 
the tree between itself and the observer.’’ Dunn (1915) 
stated that these lizards are found ‘‘Chiefly on trees and 
fences, or very rarely on the ground. They are rather 
agile and difficult to capture, save with a noose. They do 
not, as a rule, go into holes when hard pressed, though I 
have seen one hide under the loose bark of a stump.”’ 
Ditmars (1915) has found that ‘‘Captive specimens re- 
quire an abundance of sunlight and a perfectly dry 
cage.’? Wright and Funkhouser (1915), working in 
northern Georgia, found this lizard to be ‘‘ Abundant in 
higher and drier parts, and most common in the sandy 
pine lands where they seem to prefer the fallen timber, 
logs, and stumps.’’ Deckert (1918) found the pine liz- 
zard to be numerous on pine saplings and fallen timber 
in Florida. Barbour (1919) quoted Mr. A. G. Reynolds 
as writing that ‘‘When on a burnt log Sceloporus wndu- 
latus often tries to escape capture by running a short 
distance then squatting suddenly to escape notice.’’ Holt 


24 Trans. Acad. Sci. of St. Lows 


(1919) published the record of a specimen feigning death 
for over twenty-five consecutive minutes. Blanchard 
(1922) found these creatures to be very common about 
rail fences, trees, fallen logs and stumps, and in fields 
or openings in woods. In escaping a pursuer they were 
seen in no case to run on the ground. The same author 
(1925) collected a specimen on an oak tree at Twin 
Caves, Indiana. Taylor (unpublished) stated that ‘‘ They 
are often seen about roadsides in very dry or rocky 
places.”’ 

Several authors have given details which bear upon 
the life history of the pine lizard. Hay (1892) wrote 
that ‘‘The eggs are said to be laid in the sand, probably 
in little groups. They are deposited about June 1, and 
are hatched about July 10. The eggs are long ‘and 
narrow and are covered with a tough coat, and are with- 
out any caleareous material. When laid they are aban- 
doned to their fate, but the young are treated with the 
utmost tenderness by adults.’? Hay (1902) stated that 
‘‘Higes are laid early in the summer and hatch in July. 
By the latter part of August the young begin to shift 
for themselves and leave the company of the adults.’’ 
Ditmars (1915) found that eggs may be hatched by plac- 
ing them in moderately damp, not soggy, sphagnum 
moss, and keeping them at ordinary room temperature 
where their period of incubation is from six to eight 
weeks. Dunn (1915) stated that ‘‘A female caught on 
May 10, 1914, at Marlton, New Jersey, was killed and 
dissected on June 7. She had ten large eggs in her 
oviducts. My earliest record for young is July 29 (Nel- 
son County, Virginia).’? Hyde (1923) reported April 
19, 1923, as a copulation date for the subspecies in Vir- 
ginia. Speck (1924) recorded the attempted coition of 
a male of S. undulatus undulatus from New Jersey upon 


The Inzards of Kansas 25 


a female of S. spinosus from Texas. Bishop (1926) 
found a large Kentucky female on June 24, 1925, with 
eight well-developed eggs in her body. Hassler (1927) 
reported the finding of five newly hatched young in New 
York in September, 1926. They were taken ‘among the 
leaves and grass at the base of a small ledge.’? 

The above discussions indicate that from eight to ten 
eggs are laid sometime in June, and that they hatch a 
month or two later, depending upon the conditions of 
incubation. 

The food of the pine lizard consists essentially of 
small insects and spiders. 

Discussion of Kansas Records. — Because of the es- 
pecial interest aroused by the question of possible inter- 
gradation in a place where the areas of distribution of 
two supposed subspecies approach each other, this head- 
ing is deemed a necessity. Atchison County; Prof. Felix 
Nolte of St. Benedict’s College collected a pine lizard at 
Atchison in May, 1927. Cherokee County; Mr. W. H. 
Burt collected four lizards on September 6, 1926, near 
Shoal Creek, which Dr. Edward H. Taylor and the writer 
have identified as this subspecies. Geary County; Dr. 
F’. W. Cragin (1881) gave a report from this area, and, 
unfortunately, his specimens have been lost. In addition 
to this, Cope (1900) reported four Townsend specimens 
from Ft. Riley under the United States National Museum 
number ‘‘4852.’? The data upon these specimens are 
obscure. This fact, the loss of Cragin’s specimens and 
the knowledge that the distinctions upon which the two 
subspecies of S. undulatus are separated have often been 
close, is the basis of listing these as doubtful records. 
McPherson and Rooks Counties; These reports of 
Cragin (1881) are decidedly in the range of S. undulatus 
thayerii, and the specimens upon which ey were based : 


2€ Trans. Acad. Sci. of St. Louis 


have been lost. Therefore, the writer considers these 
reports as extremely doubtful-ones. Wyandotte County; 
The work of Dr. Edward H. Taylor (unpublished) gave 
this report. Since Dr. Taylor has also collected this 
lizard in Swope Park, which is but a short distance from 
Wyandotte County, and Hurter (1911) listed it from a 
near Missouri County, this record is accepted as very 
probable. 

Distribution in Kansas.—Kansas is on the very west- 
ern edge of the distribution of this subspecies. Stejneger 


Cheyenne Rawliss Decsir 


Sherman Thomas Sheridan 


Fig. 4. diaper eelpeiics of S. oo undulatus in Kansas as indicated 
e county report 


and Barbour (1923) gave the range as ‘‘Hastern States, 
New Jersey to Florida,’’ but a review of the literature 
and the examination of certain specimens indicates that 
this does not adequately express the known range of the 
lizard. Specimens from Louisiana, Missouri, Arkansas 
and Kansas, examined by the writer are S. undulatus 
undulatus, and therefore, the range should very prob- 
ably be ‘‘The Eastern States, New Jersey to Florida, 
westward to Louisiana and Eastern Kansas.’’? Since a 


The Lizards of Kansas 27 


specimen from Bloomington, Indiana, kindly sent to the 
writer by Mr. G. 8. Myers, now at the Leland Stan- 
ford University, has been identified by Miss Doris M. 
Cochran of the United States Museum as this subspecies, 
and Blanchard (1925) reported it from Twin Caves, 
Indiana, the State of Indiana as a northern point in the 
known range is established. 

The distribution of this subspecies in Kansas is prob- 
ably confined to the eastern edge. A comparison of 
figures, 3 and 4, will show that in Kansas the distribu- 
tion of S. undulatus undulatus is entirely distinct from 
that of S. undulatus thayerti, and that a space of several 
counties in which much collecting has been done, sepa- 
rates the known range of the two forms in the state. 

Phrynosoma cornutum (Harlan). 

Texas Horned Lizard, Common Horned Toad, Spiny 
Breasted Horned Lizard. 

Description—Head short; depressed; bearing promi- 
nent spines; two occipital spines, separated by a space 
in which there is a small, but easily discernable, median 
spine; two or three pairs of temporal spines of less 
prominence than occipitals; a short horn extending back- 
ward from the prominent superciliary ridge above each 
eye; muzzle descending steeply in profile; body dorso- 
ventrally compressed; stout; bearing two rows of mar- 
ginal abdominal spines; ear opening present, but often 
partly concealed by a fold of skin; both gular and neck 
fold present; upper series of labials smaller than lower 
series; sub-labials more prominent, increasing in size 
toward posterior end; tail short, broad and flattened at 
its root; dorsal scales small, excepting for sparsely dis- 
tributed spines of varying prominence and sharpness; 
ventrals larger, weakly keeled or smooth; femoral pores 
few or absent in females, more in males; enlarged post- _ 


28 Trans. Acad. Sci. of St. Lowis 


anal plates not a reliable criterion of sex in this species; 
extremities well developed. 

Coloration always dull; ventral parts white or ashy 
gray, usually with a smattering of blackish spots; dorsal 
eolor slate, brown, or blackish; vertebral stripe always 
pale or whitish, extending from occiput to base of tail; 
three pairs of dark spots along sides, these usually emar- 
ginated by pale whitish outlines; a dark spot on each 
side of neck; tail usually barred. 

Measurements taken upon 96 Kansas specimens of 
this species are summarized as follows: length of body, 
21-109 (51-60) ; length of tail, 7-44 (21-30) ; total length, 
28-148 (76-90); width of head, 6-22 (12-14); length of 
tail as percentage of total length, 21.9-34.9 (28-30) ; 
width of head as percentage of body length, 13.5-37.5 
(20-24). 

In contrast to what has been shown in other species, 
this summary indicates that there is a greater variation 
in the length of body than in the length of tail, which 
is to be expected since the tail is relatively short in 
P. cornutum. The width of the head was measured just 
back of the angle of the jaw and did not include the 
temporal spines. 

Hurter (1911) listed the total length as 110 mm., tail 
46 mm., and body 64 mm., giving a tail percentage of 
41.8, which is much larger than any noted on Kansas 
specimens by the writer. The measurements given by 
other workers for this species, so far as known, agree 
with those of the author. 

Habitat and Habits—tThere has not been a great deal 
written about the habitat and habits of this species. 
Winton (1914) and others have described the ejection 
of blood from the eye of certain specimens, but the 
writer has not been fortunate enough to observe this 


The Lizards of Kansas 29 


phenomenon. Winton (1916) stated that ‘‘The favorite 
haunt seems to be along the edge of thick vegetation.”’ 
He also gave evidence that the blood ejecting habit was 
connected with the process of molting. The same author 
_ (1917) wrote that ‘‘Male horned lizards sometimes fight 
each other in hot weather, if confined closely. ... In 
North Central Texas, the horned lizards disappear with 
the first cold burst, which usually comes between the 
middle of September and the first of October,’’ and 
(1916), ‘‘In the area of their greatest abundance they 
first appear from their winter burrows about the middle 
of April.’’ Housholder (unpublished) stated that 
‘Horned lizards are very common along roadsides with- 
in their range.’’ 


Horned lizards are strictly terrestrial in their habits, 
and are found most abundantly in dry, sandy areas 
where there is little vegetation. Hower, their distribu- 
tion is not confined to sandy areas, for they often occur 
about limestone ledges. Individuals are frequently 
found close to dwellings, and may even breed in the 
dooryard. Horned lizards frequent the highways in 
some regions and pastures are often well populated with 
them, 

The breeding habits of P. cornutwm have been rela- 
tively well studied. Edwards (1896, 1903) has excel- 
lently described the nest digging habits. Strecker (1908) 
found ‘‘A set of eggs deposited in four layers of six 
each. . . The period of incubation is about forty days 
... the eggs are usually buried to a depth of six or 
seven inches and . . . the breeding season extends from 
the middle of April into the latter part of July.”’ Giv- 
ler (1922) has given a detailed account of part of the 
life history of the species as follows: ‘‘The lizards come = 
forth about May 1. At first the males greatly pre-e 


30 Trans. Acad. Sci. of St. Louis 


dominate in numbers, but later the females come out 
of hibernation rapidly and tend to equalize the ratio. 
Matings take place freely in this early period and since 
the males are out of hibernation first, and in such num- 
bers, the insemination of the females is insured. . . In 
May before ovulation there are usually about 32 eggs 
in the ovaries. . . It is evident that maturation occurs 
immediately preceding ovulation, and that fertilization 
occurs immediately after the entrance of the eggs into 
the ostium. The same female may copulate more than 
once, but ovulation of all the eggs takes place at nearly 
the same time. . . Eggs are laid under a ledge of rock 
in dirt and nicely concealed and covered from May until 
July. The incubation period is not known.’’ Reese 
(1922) found that a female had laid three yellowish eggs 
on the night of June 7. Later, dissection showed 34 
eggs inside of the body, similar to those laid before. 
Taylor (unpublished) stated that ‘‘The period of in- 
cubation is from four to five weeks.’’ Cahn (1926) has 
called attention to the fact that a number of prominent 
zoologists have overlooked the knowledge of the egg- 
laying habits of certain species of the genus Phryno- 
soma. He has also given another interesting account 
of the nest digging habits of P. cornutum, stating that 
‘‘Qn the afternoon of May 30, 1921, I chanced upon a 
female standing motionless on her toes in the center 
of a grassless, sunbaked area. The time wals about 
6:15 p.m. After about five minutes she began to dig. 
The work was leisurely done, but progressed steadily. 
... The lizard paid not the slightest attention to me, 
so early in the game I moved over and sat with her 
between my legs, the better to watch her operations. She 
permitted me to measure the hole, submitting to handl- 
ing without objection, and resumed her digging opera- 


The Lizards of Kansas 31 


tions immediately upon being released. By 8:30 it was 
too dark to see anything clearly, so I carefully marked 
her location and left her until morning. The lizard was 
gone next morning, and there was only the slightest 
trace to mark the spot where I had watched the perform- 


ances of the previous evening. . . . Digging revealed the 
fact that the tunnel descended without turns to the depth 
of five and one-half inches. . . . This terminated in a 


circular chamber in which were laid 27 eggs, creamy 
white in color, and covered with a flexible leathery mem- 
brane.’’? Hight of the eggs were left in Texas with a 
friend and hatched on the thirty-ninth day (July 8), 
while nine were removed to Wisconsin and hatched on the 
forty-sixth and forty-seventh days (July 15 and 16). 
Both sets were kept in the original sand, so the variation 
in hatching dates was attributed to temperature differ- 
ences. Cahn also recorded the egg number in six sets 
which he had found, as follows: 27, 24, 25, 24, 23, and 25. 

The natural food of the Texas horned lizard is chiefly 
ants and other small insects. 

Discussion of Kansas Reports——Horned lizards are 
presumably absent from Northeastern Kansas. Only 
two reports are available from this area for P. cornutum. 
Douglas County; Specimens have been taken at various 
times on or near the Kansas University campus, but 
none have been taken in other parts of the county. These 
lizards are admittedly the offspring of adults turned 
loose in the vicinity. Franklin County; Dr. F. W. Cragin 
(1881) reported this species from Ottawa on the au- 
thority of Prof. Wheeler. Though specimens have been 
collected in recent years at short distances to the south 
and west of Franklin County, none have been taken 
within its boundaries. 


32 Trans. Acad. Sci. of St. Louis 


Distribution in Kansas.—The general distribution of 
P. cornutum covers the State of Kansas, with the ex- 
ception of its northeastern corner. 

Phrynosoma douglassii ornatissimum (Girard). 

Ornate Horned Lizard, Girard’s Short-horned Lizard, 
Ornamented Horned Lizard, Horned Toad. 

Description—Head depressed, with short spines ; snout 
sloping gently forward, more abruptly as base is reached ; 
tympanum exposed; occipital spine may or may not be 
more nearly vertical than last temporal spine when 


paitips | Smith | Jewen | F¢P*>!C fwasnngwa| marstalt | Nemahe 


Fig. 5. Distribution of P. cornutum in Kansas as indicated by the 
county reports. 


viewed from the side; spines set close together; median 
horn directed upward; four or five temporals, one oc- 
cipital, and one prominent postorbital on each side; 
gular scales small and of nearly equal size; labials and 
sublabials pointing obliquely backward; dorsal scales of 
different sizes; few spines on back, central portion of 
considerable width practically free from spines; one 
row of marginal spines making a fringe on each side 
of the body; ventral scales smooth and small, arranged 


The Inzards of Kansas 33 


in regular series, diagonally and transversely; both 
sexes with femoral pores; tail of female shorter than 
that of the male. ; 

Coloration variable; dorsal color pale cinnamon 
rufous, yellowish, olivaceous, pinkish, brownish, or gray, 
and with uneven blotches of darker and lighter hues; 
tail colored like body; lower surface usually white or 
pale green, but sometimes greenish or olivaceous; head 
spines reddish to pale yellowish. 

The study of variation has been made upon 36 Kansas 
specimens of this subspecies, twenty-two of which were 
small in size. A summary of the data is given below: 
Length of body, 20-91; length of tail, 9-40; total length, 
31-131; width of head, 6-24; length of tail as percentage 
of total length, 24.3-37.1; width of head as percentage 
of body length, 21.4-30.0. 

As far as observed, the measurements of other 
workers all fall within the ranges set by the above list- 
ing. 

In addition to the two horned lizards discussed above 
P. brevirostre and P. douglassii hernandesi have been 
reported from Kansas, so it is necessary to consider them 
here, 

The occurrence of P. brevirostre in Kansas has been 
regarded as very unlikely by Burt (1927). 

Through the work of Cope (1900, pp. 414-415), P. 
douglassti hernandesi was definitely reported from Kan- 
sas. After carefully comparing specimens of P. doug- 
lassit hernandesi and P. douglassii ornatissemum from 
various points the writer has come to the conclusion 
that they may be synonyms and plans to make a care- 
ful study of their status later. The points upon which 
the two subspecies are presumably separated are @ 
more nearly vertical occipital spine, as compared with 


34 Trans. Acad. Sci. of St. Louis 


the temporal spine, in P. douglassi ornatissimum, and 
likewise a smaller opening between the occipital and 
temporal spines of P. douglassit hernandest. Other vari- 
able characteristics have been used to discriminate be- 
tween the two forms, such as coloration, number of 
spines on the body, and the occipital emargination. Cope 
(1900) attributed a deeper occipital emargination to 
P. douglassu ornatissimum, but found that the young 
present the form characteristic of P. douglassu hernan- 
dest. 

The occipital spines of Kansas specimens present great 
variation in their angle of rise from the horizontal plane. 
Some, with the occipital spines pointing backward, for 
example a specimen in the museum of the Kansas State 
Teachers’ College at Hays, are probably close to P. 
douglassu hernandesi, while others with the occipital 
spine in a vertical position are no doubt P. douglassu 
ornatissimum. Moreover, there are intermediates be- 
tween these extremes. Since no great differences are 
presented by the individuals in the series of Kansas 
specimens, it seems best to draw no complicated dis- 
tinctions, and to consider them all as P. douglassu orna- 
tissimum. 

Habitat and Habits —Little has been published about 
the habitat and habits of these lizards. They are in- 
sectivorous, and have been found to give birth to living 
young. 

Discussion of Kansas Reports—Since P. douglassit 
ornatissimum is evidently a rather rare Kansas lizard, 
a detailed discussion of its Kansas reports is given here. 
Doniphan County; Report given by Cragin (1881) as P. 
douglass, and later by Housholder (unpublished) as 
P, douglass hernandesi. Cragin’s specimen has’ been 
lost, and consequently his data are obscure, and Hous- 


The Lizards of Kansas 35 


holder’s record is obviously based on Cragin’s work. 
Douglas County; Report given by Taylor (unpublished) 
with the statement that ‘‘Some specimens have been 
turned loose about the University and are occasionally 
met with by collectors.’? Edwards County; This report 
is based upon a specimen in the Museum of Zoology of 
the University of Michigan. Ellis County; This report 
is based upon a specimen in the museum of the Kansas 
State Teachers’ College of Hays. Geary County; The 
Hammond specimens reported by Cragin (1881) as P. 


Fig. 6. Distribution of P. douglassii ornatissimum in Kansas as indi- 
cated by the county reports. 


douglassii have been lost. Cope (1900) listed four speci- 
mens of the United States National Museum which were 
collected by H. Brandt as P. hernandesi, but the actual 
data of collection are obscure. Logan County; This re- 
port is based upon specimens in the Kansas University 
Museum. Rooks County; This report was given by 
Taylor (unpublished). Smith County; This report is 
based on a specimen in the Kansas University Museum. ak: 
A number of specimens labeled ‘‘Kansas’’ are 1m the ae 


36 Trans. Acad. Sci. of St. Louis 


museums of both the Kansas State Agricultural College 
and Kansas University. 

Distribution in Kansas.—The distribution of this sub- 
species in Kansas is marked by several authentic records, 
all of which are in the western half of the state. Both 
P. douglassti ornatissimum and P. douglass hernandest 
are reported from Colorado, so the general range would 
probably include the entire western part of Kansas. 


Ophisaurus ventralis (Linné). 
Glass Snake,* Joint Snake, Hoop Snake, Grass Snake, 
Joint Lizard. 


Description—Head sloping gently forward, not well 
marked off from body; snout rounded; body serpenti- 
form; tail long, usually incomplete, but tapering to a 
fine point in perfect specimens; the partly regenerated 
tail often a stub or spike; ear opening small; tympanum 
concealed; no gular fold; all scales smooth; body scales 
large, except in gular region; legs absent. 

Color pattern varied; several dark longitudinal stripes 
on sides; mid-dorsal dark stripe present; wide light band 
on each side of median dorsal line; stripes not extending 
on head, but present on tail; ventral parts uniformly 
light colored; ground color for all upper parts, light to 
dark brown, never light grayish as in many eastern speci- 
mens. 


As some of the common names imply, the tail is very 
brittle. The examination of 32 Kansas specimens of 
the species has shown only thirteen or 40.62 per cent 
with tails entire, giving a percentage of 59.38 for the 
nineteen deformed specimens. The largest amount of 


*This species is almost everywhere commonly designated as a snake 
a of its superficial resemblance to that group. However, the 

sence of ear gout and the absence of transverse ventrals shows 
its lacertilian affinit 


The Inzards of Kansas 37 


regeneration, using as a basis of calculation the second- 
ary length, was 32.35 per cent of that length. 

Measurements taken on the 32 Kansas specimens of 
this lizard, mentioned above, are as follows: Length of 
body, 56-250 ( 201-250) ; length of tail, 248-438 (301-360) ; 
total length, 294-655 (501-600); width of head, 4.5-16 
(10-12) ; length of tail as percentage of total length, 62.5- 
69.1 (68-69) ; width of head as percentage of body length, 
3.0-7.0 (4.0-6.0). 

The length attained by this species is in excess of that 
of all other Kansas lizards. Also, the width of head 
as percentage of body length is less than that of other 
species. Hay (1892) gave the total length of the largest 
Specimen which he had measured as 915 mm., a figure 
greatly in excess of the largest one examined by the 
writer. Hurter (1911) found the total length to be 
702 mm., tail 455 mm., and body 247 mm. Taylor (un- 
published) measured a large Kansas specimen which has 
since been lost. His measurements were, total length, 700 
mm., tail 456 mm., and body 244 mm. 

Habitat and Habits—This widely distributed lizard 
has often been collected. Holbrook (1842) stated that 
“‘This species chooses dry places for its abode, and 
passes much of its time in holes, or under the roots of 
old trees, and is often dug out of the earth with the 
Sweet potato at harvest time.’? Hay (1892) wrote that 
‘This animal selects for its abode, dry, rather than damp 
situations.” Ditmars (1910), during several collect- 
ing trips in the south noted a condition pointing toward 
the noctural habits of the species. ‘‘There was a scarcity 
of specimens abroad during the day, but in the early 7 
morning, however, they were found in wells, where they 


had evidently tumbled during their nightly search for . . 7 
food,’? Taylor Nps tematic stated that ‘‘One speci- - 


38 Trans. Acad. Sci. of St. Louis 


men was found late in November buried eighteen inches 
under the ground about the foot of a hedge tree. It 
was coiled and motionless, but when brought out into 
the sun it showed signs of life.’? Evidently this in- 
dividual had gone into hibernation. 

The glass snake is frequently seen by farmers who 
are tilling the soil, or working in the hay or grain fields. 
It is a burowing form and is not often seen free above 
the surface of the ground. This accounts for its ap- 
pearance in fields that are being plowed. Sometimes, 
however, the glass snake is found free above the ground, 
usually in the neighborhood of grasses or small grain 
patches. When disturbed it glides quickly away through 
the grass or weeds, a reaction which makes its capture 
diffieult. 

The glass snake feeds upon the larger insects, and very 
probably upon small rodents also. 

Distribution in Kansas.—The distribution of the glass 
snake probably includes the eastern two-thirds of Kan- 
sas. This species is almost universally reported by the 
farmers of various state localities, but it is very hard 
for the collector to secure; therefore, its distribution in 
Kansas is probably much more extensive than has been 
shown, and further collecting is expected to add to these 
data. It is interesting to note that in spite of the till- 
ing of the soil of their habitat some of these lizards are 
still able to withstand agricultural conditions, as indi- 
eated by their continued occurrence about cultivated 


areas. . . 
Cnemidophorus sexlineatus (Linné). 


Six-lined Race-runner, Six-lined Lizard, Six-lined 
Swift, Six-lined Whip-tailed Lizard, Race-horse, Sand- 
scraper, Race-nag. 

Description—Body slender; profile of snout blunter 
than that of either C. gularis or C. tessellatus; ear-open- 


The Inzards of Kansas 39 


ing rounded anteriorly, somewhat flattened posteriorly; 
tympanum exposed; two prominent gular folds; head 
plates large; dorsals finely granular; large ventrals in 
eight longitudinal rows; dorsal caudal scales plated and 
strongly keeled; Gadow (1906) stated that the number 
of femoral pores varies from fourteen to nineteen, and 
a limited number of counts made on Kansas specimens 
by the writer are within these figures; these pores with 
enlarged centers in males; small centers in females. 
Coloration extremely variable; ventral color purplish, 


Fig. 7. Distribution of O. ventralis in Kansas as indicated by the 
county reports. 


blue, greenish blue, bright green, yellowish, pure white, 

or brownish; sides dull bluish, whitish, yellowish, green- 

ish, slate or purple; sides always darker than below, 

and often one of the above colors is found on the sides 

while the abdomen is gray or whitish; back with six 
longitudinal light lines; young specimens often with a 

broad seventh stripe down the median part of the back, — 
which fades and gradually disappears as the animal = 
becomes older; dorsal ground color usually some shade : i 


40 Trans. Acad. Sct. of St. Louis 


of brown, gray, green, or yellow; upper head scales 
olivaceous; lower labials white, or light blue; upper 
labials brown, yellowish, or greenish; angle of jaw 
colored more deeply than labials; tail brownish above, 
whitish beneath. The coloration of these lizards should 
always be studied on freshly collected material or living 
specimens, for their colors fade very rapidly in pre- 
servatives. 

Data upon 169 Kansas specimens are as follows: 
Length of body, 27-79 (61-70); length of tail, 45-164 
(121-135) ; total length, 72-238 (181-200) ; width of head, 
4.5-11 (8-9); length of tail as percentage of total length, 
59.5-72.1 (66.1-68) ; width of head as percentage of body 
length, 11.1-17.7 (12-14). 

This summary indicates a greater variation in the 
length of tail than in the length of body. Pratt (1923) 
gave the total length as 250 mm., and tail 175 mm. This 
figure for total length is the greatest yet found by the 
writer. 

In discussing the genus Cuemidophorus it is well to 
note that besides C. sexlineatus, the species, C. tessel- 
latus and C. gularis, have been reported from Kansas. 
The writer has examined over 200 specimens of race- 
runners from \Kansas, and has referred them all to 
C. sexlineatus. The report of C. gularis for Kansas was 
made earlier than that of C. tessellatus and will be con- 
sidered first. 

Hallowell (1856 a-b) reported one and seven speci- 
mens of C. gularis, respectively, from Kansas. They 
were presented to the Academy of Natural Sciences of 
Philadelphia by Dr. Hammond, U. 8S. A., who was sta- 
tioned at F't. Riley, Kansas. The recent trip of the Kan- 
sas University Biological Survey through that region 
(1926) has failed to reveal any of these specimens, and 


The Lizards of Kansas 4] 


the range of C. gularis, as given by Stejneger and Bar- 
bour (1923), does not include Kansas. After consider- 
ing the obscurity of the report (1856) and the corre- 
sponding possibility of error in recording the exact 
locality of the specimens, C. gularis is withheld from the 
Kansas faunal list. 

Cragin (1884) reported C. tessellatus from Central 
Kansas, writing that ‘‘The occurrence of this species in 
Kansas was hardly expected, but a specimen of the typi- 
eal variety has been sent to me from McPherson County 
by Dr. John Rundstrom.’’ Thus it is clear that the re- 
port of this lizard for Kansas is based upon a single 
specimen, which has since been lost. The writer has 
collected and examined eight race-runners from the 
same locality (near Lindsborg) in which Rundstrom 
worked, and they are all C. sealineatus. The range of 
C. tessellatus, as given by Stejneger and Barbour (1923), 
is ‘‘Texas to California, also Utah, Colorado and Ne- 
vada.’? Van Denburgh (1922) listed it as a Kansas 
species, but Cragin’s work was cited in his bibliographic 
references, thus making evident the basis of his report. 
In view of the existing data it seems best to regard 
C. tessellatus as a species unlikely to occur in Kansas, 
and to withhold it from the Kansas faunal list. 

Habitat and Habits—C. sealineatus is probably the 
most widely distributed lizard in the United States. Its 
range, according to Stejneger and Barbour (1923), is 
‘Maryland to Florida, west to Northern Mexico and 
Arizona and up the Mississippi Valley as far north as 
Lake Michigan.’? A lizard which occurs over such an 
area is certainly able to adapt itself to a large number 
of habitats, and consequently its habitat and habits have 
been discussed by a large number of herpetologists. — 


42 Trans. Acad. Sci. of St. Lows 


Cope (1866) wrote that ‘‘They live chiefly in dry, open 
woods, among dry leaves, at the foot of bushes, ete. They 
are emphatically ground lizards, and not a tree or rock 
species.’’ The writer takes exception to the statement 
that this lizard is not a rock species, since he has found 
it under rocks in many localities. However, it is not 
always a rock species as will be shown by further discus- 
sion. Cope (1880) wrote that ‘‘It is entirely terrestrial 
in its habits and moves with greater rapidity than any 
other lizard.’’ Rhoads (1895) found that ‘‘This lizard 
was numerous in the suburbs of Chattanooga along rail- 
road embankments.’’ Ruthven (1907) specified that 
‘‘This is a characteristic form of the desert floor hab- 
itat.”” Ditmars (1915) stated that ‘‘They frequent dry, 
sandy places and borders of dusty roads. When 
disturbed they dart into their holes or burrows with 
lightning like rapidity.’’ Wright and Funkhouser (1915) 
wrote that ‘‘It is found in plowed ground and cornfields, 
and seems to prefer the bare furrows for sunning. . . 
They dart into holes in the raised earth between the fox 
rows when disturbed. The burrows extend in an irregu- 
lar direction to a depth of eight or ten inches.’’ Holt 
(1919) found that a young specimen was very restless, 
and the moment it was released, it darted away with the 
speed characteristic of the species.’’ Blanchard (1922) 
wrote of specimens of western Tennessee, ‘‘They are 
extremely common in sandy situations near Henry and 
are always found on the ground. They are swift and 
escape by running into grass or brush. Overnight, some 
at least, remain in holes dug in the sand, from which they 
may easily be taken early in the morning. The burrow is 
short and has two openings, and when the lizard is in- 
side one of these openings is partially filled with sand 
thrown out from within.’’ Hallinan (1923) observed 


The Inzards of Kansas 43 


these race-runners going in and out of gopher tortoise 
burrows in Florida. Dr. Edward H. Taylor of Kansas 
University in a recent interview stated that while he was 
collecting in Tennessee during the summer of 1926 he 
found C. sexlineatus occuring abundantly in a heavily 
forested region on a bank of the Tennessee River, over 
which rose a hill that was covered with limestone ledges. 

The writer has often collected this lizard. It frequents 
a greater variety of habitats than all other Kansas spe- 
cies, and it seems that only a high moisture content of 
the surface soil restricts its distribution, since it has 
often been collected from rocky ledges and sandy areas, 
but only rarely from loamy situations. It has been found 
on rocky hillsides, open corn and wheat fields, upland 
meadows, low sandy river banks, about chalk cliffs, rail- 
road embankments, road beds, sand dunes, isolated sand 
banks, occasional out-croppings of rock, and on the up- 
per part of wooded hillsides. These creatures are often 
found close to dwellings, and are apparently able to 
adapt themselves to changes brought about by agricul- 
tural conditions. 

These race-runners are probably the swiftest of Kan- 
sas lizards. Taylor (unpublished) found them to be very 
common in the chalk cliffs of Trego and Gove counties, 
but obtained only a small number because of their great 
agility. No doubt the swiftness of this lizard in escaping 
its numerous enemies, including man, is responsible in 
a large measure for its ability to survive even in the 
more populated districts. : 

In regions where there are no rocks for hiding, mem- 
bers of this species dig holes in which they stay at night. - 
These holes are probably used repeatedly, and often 
when a specimen is disturbed in the day time it runs 


rapidly away, and finally ees into one of them. ae 


44 Trans. Acad. Sci. of St. Lows 


In Wilson County, near the towns of Neodesha and New 
Albany, many burrows were observed in the graveled 
right of way of the Frisco railroad. These lizards are 
very graceful and their running movement is even. Speci- 
mens running at top speed always went in a straight 
line, all four legs being employed in perfect unison. A 
distinct elevation of the body is accomplished by the 
straightening of the legs, so that the body is carried 
parallel to and distinctly above the ground. 


The writer has carried a small revolver with him while 
collecting, and has obtained large numbers of specimens 
with shot shells. Many of these could not otherwise have 
been taken. In order to get the most specimens in the 
least time the habits of these creatures were studied, and 
often peculiarities in their behavior were used to maneu- 
ver them into the open. Short, swift runs are often made 
by C. sexlineatus when it is disturbed. These are fol- 
lowed by pauses during which it holds its head high in 
the air in a manner indicating keen alertness and watch- 
fulness. If the disturber moves away, the lizard usually 
remains motionless, but if he comes closer, the animal 
soon darts to another position. Usually movements to 
the side do not cause the lizard to run. Always the move- 
ment of the observer must correspond to the rest pe- 
riods of the lizard. The movement of the lizard is be- 
trayed by a faint rustle which is readily perceived by 
the collector. 


The six-lined race-runner is perhaps the most gre- 
garious of all our lizards. Specimens were nearly always 
found at certain points, even though the collector re- 
turned again and again, whereas, at points not far away, 
which looked equally attractive as a habitat, no speci- 
mens were seen. Thus, localization of the habitat in defi- 
nite areas seems to be characteristic of the species. At 


The Inzards of Kansas 45 


Lawrence this lizard was collected along the Union Pa- 
cific railroad track amid coarse rock and considerable 
vegetation very close to the Kansas River. A specimen 
was driven into a rock cliff in Washington County and 
was dug out only after the removal of a considerable 
amount of rock. It had followed a small tunnel for a dis- 
tance of almost five feet. 

The breeding habits offer a good field for further 
study. Ditmars (1915) stated that ‘‘This species lays 
thin-shelled eggs." The female scrapes out a small hol- 
low in the sand, and carefully covers the eggs, leaving 
them to be hatched by the sun’s heat.’’ Wright and Funk- 
houser (1915), working in Florida, found that ‘‘The 
€ggs were deposited in irregular burrows between fur- 
rows in a plowed field. These burrows were eight to ten 
inches deep. The eggs, measuring about sixteen by ten 
millimeters in size, and deposited in sets of four or five, 
are laid in June.’’ 

Six-lined race-runners are very fond of spiders and 
many small insects, especially grasshoppers and Lepi- 
doptera. A number of snails have, also, been found in 
stomachs examined. 

Distribution in Kansas. The six-lined lizard appears 
to be distributed throughout the state and has been re- 
ported from all adjoining states. It has already been 
mentioned that C. sealineatus, Sceloporus undulatus 
thayerii, and Holbrookia maculata maculata are the only 
Species taken in certain parts of western and central 
Kansas. In the isolated outcroppings of rocks which are 
found in Washington and Republic counties, this lizard 
and Eumeces obsoletus are the only species reported, and 
they have frequently been found together. 

Leiolopisma laterale (Say). 

Ground Lizard, Brown Backed Lizard. 


46 Trans. Acad. Sci. of St. Louis 


Scincus lateralis Say, 1823, Long’s Exp. Rocky 
Mts. 2:324, (type locality, ‘‘Banks of the Mis- 
sissippi River below Cape Girardeau, Mis- 
souri’’). 

Scincus unicolor Harlan, 1825, Jour. Acad. Nat. 
Sci. Philadelphia, 5:156. 

Lygosoma laterale Cragin, 1881, Trans. Kansas 
Acad. Sei., 7:118. 

Leiolopisma laterale Jordan, 1899, Man. Vert, 
Northern U. S., ed. 8. p. 201. 

Description—Body elongated, cylindrical; limbs min- 


Fig. 8. Distribution of C. sexlineatus in Kansas as indicated by the 
county reports. 

ute; ear-opening present; scales small and arranged in 

longitudinal rows. 

Coloration with little variation; body with a broad, 
dark brown band on each lateral surface; also, a broad 
dorsal band of bronze or light brown; back often with 
minute flecks of dark brown which are arranged in a 
more or less regular row on each side of the vertebral 
line; lateral stripes extending on head and tail; ventral 
parts white, silvery, or yellowish in color. 


The Inzards of Kansas 47 


Data taken upon 48 Kansas and Arkansas specimens 
of this species are as follows: Length of body, 19-81 
(41-50) ; length of tail, 23-84 (61-70) ; total length, 49-136 
(91-120) ; width of head, 3-6 (4-5); length of tail as per- 
centage of total length, 45.5-75.5 (60-65); width of head 
as percentage of body length, 7.4-15.8 (10-12). 


Since the tail of these lizards is very brittle and breaks 
easily many specimens are found with short or incom- 
pletely regenerated tails. All measurements given in the 
literature for this species, so far as known, fall within 
the ranges given in the above listing. 

Habitat and Habits—The ground lizard is found to 
range over a large part of the eastern and southern 
United States, and Kansas is on the extreme western 
border of its range. Holbrook (1842) stated that ‘‘This 
Species may be found by the thousands in the thick for- 
ests of hickory and oak in the Carolinas and Georgia. 


They emerge from their retreats after sunset, in 
search of small insects and worms on which they live. 
They take shelter quickly when disturbed, and do not 
climb.’? Hay (1902) found this lizard to occur ‘‘Most 
often under logs in rather damp situations.’’ Ditmars 
(1915) wrote that ‘‘It is very secretive in its habits and 
leads a burrowing life. Large numbers of specimens 
are found under the loose bark of fallen trees.’’? Wright 
and Funkhouser (1915) gave the distribution of some 
specimens taken in Georgia as follows: ‘‘One was found 
under the bark of a log at the edge of a small stream. 
The log was almost in the water. One was found under 
leaves in the woods, and the rest on the ground in open 
Spaces.”? Deckert (1918) stated that this lizard is 
“Common under bark in damp situations.”” 


48 Trans. Acad. Sci. of St. Louis 


Ground lizards taken in Kansas have always been 
found in woods or very near to them. Some live among 
the rocks on wooded hillsides, usually near a stream, 
but more inhabit the damper, heavier woods. There ap- 
pears to be little doubt that a humid character of the 
surface soil favors the occurence of this species, and con- 
versely, that a lack of moisture in the surface soil re- 
stricts its distribution. The writer has often taken speci- 
mens by turning over hillside rocks in the spring. In the 
summer the ground lizard is seldom found under rocks, 
but oceurs then under the dead leaves and grasses of the 
woodlands, where its presence is often betrayed by a 
slight rustle. Attempts to capture these creatures often 
result in failure because of their wonderful agility and 
the extreme brittleness of their tails. In a few instances 
the writer has been able to secure a specimen by grasp- 
ing a handful of leaves in which the lizard had concealed 
itself, 

Very little has been recorded about the breeding hab- 
its of this diminutive lizard. Strecker (1908) found that 
‘‘The eggs of L. laterale are three or four in number, and 
are deposited under the bark of fallen trees, or in hollow 
logs. They measure about nine or ten millimeters in 
length.’’ The dissection of a specimen from Douglas 
County, Kansas, revealed the presence of six eggs in 
the oviducts. 

Distribution in Kansas.—As indicated by the map, L. 
laterale is generally distributed over the eastern third of 
Kansas. This area, characterized by streams with wood- 
ed banks, receives the greatest amount of the rainfall 
of Kansas as indicated by the report of the Weather 
Bureau, United States Department of Agriculture 
(1923). Dry and sandy areas do not yield this species, 


The Inzards of Kansas 49 


and, therefore, it will probably not be taken in western 
Kansas. 
Eumeces anthracinus (Baird) 

Coal Skink, Black Skink, Anthracite Skink. 

Description—Ear opening present; all body scales in 
longitudinal rows; legs only moderately stout; cheeks 
never buldging; toes elongated; nails short. (A co-type 
in the United States National Museum has short toes and 


Morton [ Stevens Seward 


heavy, thick limbs, according to information kindly fur- 
nished by Dr. L. Stejneger.) 

Coloration varies somewhat with age; young, usually 
with an almost uniform blackish color; however, as a re- 
sult of differential coloration, a broad, jet black band 
may be seen on each side, but it sometimes requires a 
careful examination to do this; adults, usually lighter 
in color; ventral parts bluish or yellowish; upper sur- 
face uniform blackish or olivaceous; all specimens w:th 
an intense, dark, broad band on each side, bordered 
above and below by narrow light lines; the wide dorsal 


50 Trans. Acad. Sct. of St. Lours 


band uniform in color, darker than upper bordering 
stripes, lighter than lateral bands. 

Seventeen Kansas specimens of this species have been . 
measured, and the data are as follows: Length of body, 
23-61; length of tail, 38-96; total length, 70-146; width 
of head, 4-9; length of tail as percentage of total length, 
47.0-65.8; width of head as percentage of body length, 
13.1-16.0. 

A longer specimen than any designated in the above 
summary was examined by Hurter (1911), who gave the 
total length of the coal skink as 157 mm., tail 101 mm., 
and body 56 mm. 

A Kansas lizard, collected by Mr. Jack Sterling at 
Carlton, Dickinson County, Kansas, has been recently 
identified by the United States National Museum as EL. 
pluvialis. Dr. L. Stejneger and Miss Doris M. Cochran 
have compared this specimen with the co-type of E. 
anthracmus and find that the former has long toes, and 
delicate, slender limbs, in contrast to the short toes, and 
heavy, thick limbs of the co-type of E. anthracinus. 

A detailed study of the variation presented by speci- 
mens of E. anthracinus* from various points throughout 
its range, and also related work with other species of 
lizards, has clearly indicated to the writer that the length 
of both the legs and toes is a highly variable characteris- 
tic, which, though of considerable importance in deter- 
mining affinities, is usually not of primary significance in 
the identification of closely related species. Therefore, it 
appears that EH. pluvialis may be a synonym of E. an- 
thracinus, and consequently, all Kansas specimens of this 
section of Eumeces will be discussed here under the head 
of E. anthracinus. 


*The writer intends to present these data, and also a discussion of 
the relationship between E. anthracinus and E. pluvialis in a forth- 
coming paper. 


The Lizards of Kansas 51 


Habitat and Habits—The coal skink is a rare lizard 
and records of its habitat and habits have not been found 
by the writer in the literature. This species oceurs in 
Franklin County in considerable abundance, and accord- 
ing to Mr. Howard K. Gloyd, now of the Kansas State 
Agricultural College, it is found under hillside rocks, as 
are many other species of Humeces. It feeds upon a va- 
riety of small insects and, so far as known, is entirely 
insectivorous. 

Discussion of Kansas Reports.—Since this is the first 
work to report the occurence of this species in Kansas, 
all available state records are here given in detail. 
Anderson County; Report based on a specimen in the 
Kansas University Museum. Dickinson County; This 
report is based on a specimen in the Kansas University 
Museum which has been referred to E. pluvialis by Dr. 
L. Stejneger; the record of this specimen (No. 744) is 
under the name of E. anthracinus. Franklin County; A 
fine series of these skinks, most of them collected by Mr. 
and Mrs. Howard K. Gloyd, are in the museum of Ottawa 
University. Miami County; This report is based on a 
specimen (No. 201) in the museum of Ottawa University. 

Distribution in Kansas—The coal skink is evidently 
confined to the eastern half of Kansas in its distribution, 
and its known range is within that of E. fasciatus. 

Eumeces fasciatus (Linné). 

Five-lined Skink, Blue-tailed skink, Scorpion, Striped 
Lizard, Red Headed Lizard. 

Description—Body elongated, sub-cylindrical ; head 
widest anterior to the ear opening; all scale rows longi- 
tudinal; sides of head generally bulged in adult males, 
usually not in females; either one or two transverse 
mentals present under chin. 

Coloration varies greatly as these lizard develop; em- 


52 Trans. Acad. Sci. of St. Louis 


oa 


bryos with five whitish longitudinal lines on body at 
least two weeks before time of hatching; newly hatched 
young with brilliant blue or purplish blue tails; body 
dark in color; all lines distinct; median line bifurcating 
on head; as young develop the dorsal surface becomes 
grayish, and undergoes a differential coloration, each 
scale having a perceptibility lighter area in its center 
which is continuous with a lighter emargination of the 
posterior border, the anterior and lateral borders 


Wallace | Logan | Gere Trego Ellis 
: nents 
Greeley | Wichita | Soo | Lane Neos Rosh Berto 7 a Sets 
Rice McPhersca Marion Recess 
Pawnee . Cotes BEY tine 
Piso Hodgeman bir. ot 
Tsmitsyy | Kearney eee Paes SS Harvey ~, 
NaI er men Ease 
| Miserts FO Greeaweoa | Wootson | Alten 
Stanton | Grant ra | Kiowa Kingman p—————1_ witsen | Necsbo 
i — ik — 
wr | oo gewera | MO4* | Cork | nosche| Barber E | Sumner Cowley bau 


Fig. 10. Distribution of E. anthracinus in Kansas as indicated by the 
county reports. 

darker; sides remaining dark between and below the two 
lateral stripes; adults becoming lighter above and then 
later laterally; all stripes tend to become obsolete with 
age in both sexes, the center stripe disappearing before 
the lateral stripes; cheeks of adults red, or brownish red, 
in color; all stages white under head, and also in gular 
region; under surface of legs often light; other ventral 
parts dark, usually slate colored. 

Data upon 93 Kansas specimens of this species fol- 
low: Length of body, 22-90 (61-70); length of tail, 22- 


The Lizards of Kansas 53 


119 (81-90) ; total length, 50-189 (136-150) ; width of head, 
4-15 (8-10); length of tail as percentage of total length, 
44.0-65.2 (60-65); width of head as percentage of body 
length, 11.8-20.8 (14-16). 

All works that the writer has consulted give larger 
maximum measurements than those of the above sum- 
mary. Harlan (1829) gave, under the synonymous name, 
Scincus erythrocephalus, the measurements of what was 
probably a large adult male, as total length 254 mm., tail 
165 mm., and body 89 mm. 

Habitat and Habits—The western edge of the distri- 
bution of this species passes through Kansas. The five- 
lined skink is common in many parts of the southern and 
eastern United States, as well as at some central and 
northern points. Holbrook (1842) wrote that ‘‘The 
young live mostly on the ground, but the adults ascend 
trees and are seldom seen on the ground. . . . Some- 
times adults utilize old woodpecker holes for their 
abode.’? Smith (1882) found these specimens ‘‘Under 
bark in May.’? Rhoads (1895), working in Tennessee, 
found the five-lined skink in the western lowlands only. 
Hay (1902) stated that ‘They are very shy and timid, 
and spend much of their time hidden under leaves and 
bark or in trees.’? Allard (1909) wrote of Georgia speci- 
mens as follows: ‘‘They are very common. In every field 
and wood they may be found basking in the sun or run- 
ning with great rapidity over the ground. They are fre- 
quently found under the bark of fallen trees, and decayed 
stumps.’? Wright and Funkhauser (1915) also wrote of 
Georgia specimens ‘‘They are often found in deserted 
buildings, in chimneys, and also on fences, but seldom 
Seen on the ground or on trees.’’? Deckert (1918) stated 
that this lizard ‘“‘Inhabits hollow trees, always near 
water.’’ Blanchard (1925) found ‘‘Two small speci- 


54 Trans. Acad. Sct. of St. Louis 


mens, which were taken from under the bark of a log 
over a small stream in heavy woods in Vanderburgh 
County, Indiana.’’ Taylor (unpublished) stated that 
‘“‘They are usually found under stones around limestone 
eliffs.’’ Bishop (1926) found a Kentucky specimen un- 
der a railroad tie. 


The five-lined skink has been taken in a variety of 
Kansas habitats, but nearly always in wooded situations 
very similar to those occupied by the ground lizard, 
Leiolopisma laterale. A humid character of the surface 
soil is probably more favorable to this species than to 
any other North American member of the genus Eume- 
ces, and heavy woods, especially those with rocks and 
underbrush which are near a stream, are typical of the 
Kansas habitat of EH. fasciatus. North of Neodesha, 
Wilson County, on July 27, 1926, three recently hatched 
blue-tailed young were taken along the edge of the Ver- 
digris River among large fallen rocks from a ledge which 
rose 30 to 40 feet above. A spot near the town of Fall 
River, Greenwood County, where rocks tower 20 to 40 
feet above the Frisco right of way, also yielded three 
young specimens on the following day. The bed of the 
Fall River was on the opposite side of the railroad track, 
and the humid nature of the habitat was clearly indicated 
by a growth of mosses and ferns at the base of the rocky 
ledge. After a climb to the top of the ledge no more 
specimens of FE. fasciatus were observed, but a specimen 
of C. sexlineatus was taken. 


Northwest of New Albany (Elk County) an adult 
specimen was observed in a tree about fifteen feet from 
the ground. Another specimen was found at sunset 
playing on an old dead log in a cemetery. While collect- 
ing at Lawrence, Douglas County, a medium-sized speci- 


men was observed to run into a hollow stump about three © a 


The Inzards of Kansas 55 


feet high. The holes at the bottom and at the top of the 
stump were both closed. Then a sack was placed over 
the bottom hole which was opened while the top one was 
left closed. The lizard would not, however, go into the 
trap prepared for it as a snake would probably have 
done. The principle was reversed, the bottom hole be- 
ing plugged and the top one opened and covered with 
the sack, whereupon the skink ran upward and was cap- 
tured. 

Several writers have written notes bearing upon the 
breeding habits of E. fasciatus. Smith (1882) found 
that ‘‘It lays nine oval eggs at a time.’’? The egg sets 
found by Strecker (1908) were all of eight eggs each. 
Allard (1909) reported the finding of seven eggs in a 
cavity under the bark of a rotten log. A total of twelve 
eggs were recorded for a female by Dunn (1920). After 
collecting in western Tennessee, Blanchard (1922) wrote 
that ‘‘An adult female with nine eggs was found on July 
12, under the loose bark of a fallen tree in the woods. 
The eggs appeared to be in no special cavity, but merely 
lay in the damp rotted wood, between the bark and the 
harder wood beneath.’’ Lindsdale (1927) reported see- 
ing young in Doniphan County, Kansas, as early as June 
12, 1923, but the writer is inclined to believe that they 
were some that had hatched during the previous season. 

A female collected at Lawrence, Douglas County, by 
Mr. W. H. Burt on May 17, 1926, laid a set of six eggs 
on June 12. Another female with eleven eggs was taken 
in the same locality on June 18. Both the skink and the 
eggs were found in an old rotted log which oceupied a 
shaded position near a creek bed. Young of this species 
were found by the Kansas University Biological Survey 
about July 26, 1926, in Anderson County, Kansas, and 
it is the opinion of Dr. Edward H. Taylor of Kansas 
University that they were newly hatched. 


56 Trans. Acad. Sci. of St. Lows 


Through the courtesy of Dr. Taylor the writer is able 
to present data gathered on an expedition of the Kansas 
University Biological Survey to Arkansas in 1926. Egg 
sets found are recorded as June 20, nine eggs; June 25, 
two sets of nine eggs each; July 2, nine eggs; and 
July 13, ten eggs. No newly hatched young had been 
seen as late as July 22. 

The food of the E. fasciatus consists largely of in- 
sects and spiders. 

Distribution in Kansas.—This lizard is evidently con- 
fined in its distribution to the eastern half of Kansas. 
It does not occur in rocky ledges of the prairie as does 


Cheyenne Rawtins Decatar | Norton 


=l=1=|= 


Fig. 11. Distribution of E. fasciatus in Kansas as indicated by the 
county reports. 

E. obsoletus, and in addition sandy areas, chalk beds, and 
grass lands do not harbor it. Thus, the five-lined skink 
is apparently confined to the protection of thick woods. 
Eumeces multivirgatus (Hallowell) . 
Many-lined Skink, Hallowell’s Skink, Hayden’s Skink. 
Description.—Body moderately slender; ear opening 


The Lizards of Kansas 57 


small; all scale rows on body longitudinal; legs rather 
poorly developed. 

Back with seven or more brownish, almost obsolete 
stripes; vertebral stripe widest; dark bands bordering 
pale stripes; some of the light stripes very narrow, and 
others wider, more prominent; dorsal ground color dis- 
tinct grayish brown to olivaceous; abdomen grayish; 
under parts of extremities, head and tail, all lighter; 
tan to whitish; differential coloration evident in dorsal 
scales of larger specimens. 

A many-lined skink from Greeley, Colorado, has been 
measured. It has a partly regenerated tail, so only an 
incomplete set of data can be given from it. The body 
is 55 mm. in length, and the head width is 7 mm. The 
width of head expressed as percentage of body length is 
12.7. Pratt (1923) listed the tail as ‘‘Three-halves length 
of body,’’ a measurement that gives a tail percentage of 
60.0. : 

Discussion of Kansas Reports—The writer has never 
seen a Kansas lizard of this species, so takes this op- 
portunity to present the records upon which he has ad- 
mitted it to the state faunal list. In a letter dated Sep- 
tember 9, 1926, Dr. L. Stejneger wrote that ‘‘In 1915 
and 1916 Mr. V. H. Housholder sent me some Kansas 
skinks for identification. One from Labette County, I 
identified as E. epipleurotus, which I now consider as 
identical with E. multivirgatus. Another from Ander- 
son County I identified as E. leptogrammus. This I also 
consider a synonym of E. multivirgatus.’’ Although the 
writer has been unable to find these specimens in the 
present collection of the Kansas University Museum, he 
feels little hesitancy in listing E. multiwirgatus as a Kan- 
8as species with the above identifications as the basis. 
The work of Cope (1900, p. 655) listed a specimen of 


58 Trans. Acad. Sct. of St. Lows 


E. multivirgatus from Ft. Kearney, Kansas. In a letter 
dated January 3, 1927, from Miss Doris M. Cochran of 
the United States National Museum, the following infor- 
mation concerning this report is given ‘‘ Regarding 
Cope’s listing of LE. multivirgatus from Ft. Kearney, 
Kansas, and soon after, E. septentrionalis from Ft. 
Kearney, Nebraska, Dr. Stejneger says that ‘Kansas’ 
is a mistake. The specimen is the type of E. epipleu- 
rotus.”’ Cragin (1881) listed a specimen of the many- 
lined skink from Neosho Falls, Woodson County. 

Distribution in Kansas——The distribution of EH. multi- 
virgatus in Kansas is at present confined to the eastern 
part of the state, but since specimens have been taken in 
Colorado, there is the possibility of its occurence further 
west. 


Oveyenne | Rawlins | Decatur | Norte | phinipe | Smith | Jowen | RePsblic Marebalt | Nemabe | °°" 
Cloud Atchison 
Sherman | ‘Teomaa | Sberidah | Gratam | Rooks | Ostome | Mitchell Cay | Rey — Learenwortt 
Wyandote 
Ontaws 
Lincoln 
Wallace ‘ — Geary 
Lege Gove ‘Trego Elis Russi {| | abaansen = pee 
Dickinson Doogias | Johnscs 
pana Salize 
or ts gical ~ wags 
Greaag | Wichita | Seo | Lane Ness Reh pare Franklin} Miant 
= McPherson’ toe 
al meee! go pares 
Pawnee Coffey [5 Soh tse 
Panay Bodgenan Sa oh 
Hamilton } Kearney a bus rte gekieeey: ' 
~~ Bora haus Sedgwick ; 
Stanton | Grant | Haake Kiowa Kingman Wilecn | Neosho 
— eee = 
= Paci 
Stereme | Seward — Clarke Comanche | Barber Harper Sumner Cowley cid 
i, 
Mis gst 


Fig. 12. gti of on ee in Kansas as indicated by 
county report 
Eumeces obsoletus (Baird and Girard). 
Sonoran Skink, Common Gray Skink, Blue-Spotted 
Skink, Little White-Spotted Skink, ‘‘Black Skink,’’ 
‘*Blue-tail Skink of Kansas.”’ 


The Lizards of Kansas 59 


Plestiodon obsoletum Baird and Girard, 1852, 
Proc. Acad. Nat. Sci. Philadelphia, 6:129 
(type locality, ‘‘Valley of the Rio San Pedro, 
tributary of the Rio Grande del Norte, 
Texas’’). 

Lamprosaurus guttulatus Hallowell*, 1852, Proe. 
Acad. Nat. Sci. Philadelphia, 6:206. 

Description—Head not well marked off from body; 
body elongated, largest diameter in center; tail long and 
tapering in perfect specimens; supraoculars large; tym- 
panum easily seen in young, but sunken in the adult; 
ventral and dorsal scale rows longitudinal; lateral scale 
rows oblique as in E. longirostris Cope of the Bermuda 
Islands (unlike those of all other Kansas skinks) ; legs 
thick and shortened, especially in adults. 

Coloration varies greatly between young and adult 
stages; young have been described as E. guttulatus; ven- 
tral color of young blackish, slate, or olivaceous; dorsal 
color coal black to light gray; back with or without five 
faint, almost obsolete lines; sides intermediate; tail bril- 
liant blue; head scales usually shiny black; head and 
neck with white spotting; white spots on labials may be 
with partial, complete, or no inclosing black margins; 
head with or without white spot back of ear opening; 
neck with or without lateral white spots; as the speci- 
men grows older, the coloration becomes lighter, the dis- 
tinct white spotting on the head and neck is lost, and the 
dark scutellation, with special reference to that on the 
back, changes from scales with a solid color to those 
having a dark edge with a light spot in the center. Adult 


resi 

The writer has just completed a manuscript on “The Synonomy, 
Variation and Distribution of the Sonoran skink, Eumeces obsoletus 
(Baird and Girard),” in which his reasons for this synonomy are set 
forth. This work is to appear in the Occasional Papers of the Museum 
of Zoology, University of Michigan. 


60 Trans. Acad. Sci. of St. Louis 


ground color varies from blackish to light gray or oliv- 
aceous; ventral parts light to slate, often yellowish; 
lower labials and under parts of upper labials white or 
nearly so. 

Data upon 150 Kansas specimens of E. obsoletus may 
be presented as follows: Length of body, 30-121 (91- 
100) ; length of tail, 36-168 (121-135) ; total length, 66-283 
(226-250) ; width of head, 5-20 (14-16); length of tail as 
percentage of total length, 44.1-62.4 (56-58); width of 
head as percentage of body length, 11.8-19.5 (14-16). 

Ellis and Henderson (1913) gave the total length of 
this species as 305 mm. This figure exceeds that of the 
writer, and equals the maximum figure given by Ditmars 
(1915). Other measurements are not given by these 
authors. 

Habitat and Habits.—A survey of the literature shows 
that very little has been written on the habitat and habits 
of this form. Grant (1927) has discussed the behavior of 
a ‘‘blue-tailed’’ captive at some length. As indicated by 
studies in Kansas the Sonoran skink is able to live in a 
number of situations. It has been found in company 
with Leiolopisma laterale and E. fasciatus on thickly 
wooded hillsides in Douglas County, and with Crotaphy- 
tus collaris in Riley and Cowley counties situated in the 
vicinity of rocky prairie ledges above the wooded hill- 
sides. In the spring of 1925, near the town of Haddam, 
Washington County, several specimens were taken from 
isolated outcroppings of sandstone where no trees were 
present. Specimens have not been taken in exclusively 
sandy areas, nor in the grassy Kansas prairie where 
there are no sheltering rocks. Six specimens were taken 
from limestone ledges near Haverhill, Butler County, in 
July. They were not found on the tops of the hills, but 
in the dips of valleys, where, no doubt, the soil humidity 


The Lizards of Kansas 61 


was greater. One of these specimens was taken from 
under a rock in company with a medium-sized bull snake, 
Pituophis sayi, and two small sand snakes, Tantilla gra- 
cis. In Ottawa County these Sonoran skinks were very 
active in a place called ‘‘Rocky Fern,’’ an area of rocks, 
sand, and sparse vegetation. Here they were found asso- 
ciated with Cnemidophorus sealineatus which was pres- 
ent in large numbers. 

This species has been collected in Kansas from March 
27 to October 9. It is one of the earliest lizards to come 
out of hibernation in the spring, and perhaps the earliest 
to hibernate in the fall, since fall collecting, as a rule, 
yields very few of them. The specimen which was taken 
on October 9 (1925), was buried about ten inches in the 
earth beneath a large rock, and was inactive when taken. 

During the course of this study several copulation 
dates have been recorded for this species, namely, May 
8, 1926; May 17, 1926; June 13, 1927; and June 15, 1927. 
The first two records are based on the same pair of in- 
dividuals, but the last two are based on one female and 
two males. The copulation upon the second date lasted 
about four minutes. The act was preceded by a series of 
maneuvers, which ended in the grasping of a liberal fold 
of skin from the side of the female’s neck, by the male, 
and the twisting of the latter’s body beneath that of the 
female. 

Eggs have been laid on June 18, June 26, and July 1, 
in Kansas. A female which was collected at Manhattan, 
Riley County, Kansas, on April 27, 1927, laid the fol- 
lowing eggs in captivity at the Biological Station of the 
University of Michigan, Cheboygan County, Michigan: 
July 1, two; July 2, five; July 3, one; and July 7, one. 
This makes a series of nine eggs which were laid in the 
period of one week. The eggs were white in color when 


62 Trans. Acad. Sci. of St. Louis 


laid and averaged about 11 by 18 millimeters in size. 
An adult female from Marshall County, Kansas, was dis- 
sected and found to contain fifteen eggs, the anterior one 
being lodged in a position between the front legs. 

On August 13, 1926, the first blue-tailed young speci- 
men was collected by the Kansas University Biological 
Survey in Cowley County, Kansas. 

The Sonoran skink is a voracious feeder when in the 
open, and is very fond of caterpillars, grasshoppers and 
moths; however, it remains in concealment beneath the 
surface of the ground much of the time. In one instance 
a large male was observed devouring a recently laid egg 
of the species, taking it in his jaws and apparently swal- 
lowing it whole. 

Distribution in Kansas.—Hurter (1911) did not report 
this species from Missouri, so Kansas is very probably 
on the eastern border of its range. The map indicates 
that the distribution of E. obsoletus is general over the 
state. As has already been stated, the Sonoran skink 
has been found in company with many other species of 
lizards, and is, perhaps, next to Cnemidophorus sex- 
lineatus, the species with the most diversified habitats in 
Kansas. The difference in the type of habitat selected 
by the two species, EL. obsoletus and C. sealineatus, which 
are sometimes found together locally, can be explained 
as apparently that of soil humidity range, the skink be- 
ing found in damper situations than the race-runner, 
though the general area occupied by each overlaps to a 
great extent as a comparison of their distribution indi- 
cates. 

While making this study the writer has kept separate 
records for young skinks which might be identified as 
E. guttulatus from its original description, and has found 
that when reports of such lizards are plotted on a map, 


The Lizards of Kansas 63 


they are in co-extensive distribution with the adult, EZ. 
obsoletus. The one exception to this synonymous occur- 
rence is in Sumner County where only the LE. guttulatus 
form has been taken. However, Sumner County lies 
next to Cowley County where a considerable number 
of adult specimens have been collected. 


Ewmeces septentrionalis (Baird). 
Black Banded Skink, Northern Skink, Western Skink. 
Description—Body elongated, with longitudinal scale 
rows; legs moderately diminutive; coloration varies 
with age; young with two prominent light lines and two 


eee a 
Fee ee 
"os | 


Fig. 13. Distribution of E. obsoletus in Kansas as indicated by the 
county reports. 

or three dark brown bands on each side; wide mid-dorsal 
band of light brown present; adults with same number 
of stripes and bands, the general coloration becoming 
lighter with age; dorsal band between the two upper 
lateral dark stripes subdivided by two faint brown or 
blackish stripes into three light bands, one of which is 
vertebral in position; tip of snout salmon to light gray; 
ventral parts slate; lighter anteriorly. 


» 


64 Trans. Acad. Sct. of St. Louis 


The data obtained from 25 Kansas specimens are sum- 
marized below. Length of body, 34-78; length of tail, 
69-124; total length, 108-202; width of head, 4-11; length 
of tail as percentage of total length, 60.0-71.2; width of 
head as percentage of body length, 11.8-15.9. 

The writer has not found measurements given for this 
skink in the literature. 

Habitat and Habits —Very little has been written con- 
cerning the habitat and habits of this species. Ruthven 
(1910) stated that ‘‘It was found in the uplands and in 
the higher meadows, but only rarely. . . . Its prin- 
cipal habitat is undoubtedly the upland prairie.’’ Over 
(1923) found that it lives in grassy places near thickets, 
but is difficult to see by the casual observer. 

The author is indebted for some fine information con- 
cerning the Kansas habitat of this skink to Mr. F. F. 
Crevecoeur of Onaga, Pottawatomie County, Kansas, 
who has sent him a number of specimens with written 
accounts of their habitat and capture. Some extracts 
from his several letters follow. ‘‘While hunting ground 
beetles I have found as many as four of the northern 
skinks a day along a valley in a pasture about a mile 
from my home. Several times I have seen a specimen in — 
my dooryard crawling through the grass near the path 
leading to the barnyard. I believe that it has made its 
home in the wood pile. . . . Some other places that I 
have seen this species, which is about the only one that 
occurs around here, are under stones in a dry ereek bed; 
along a timbered creek under stones and at the foot of a 
stony hill which was at the side of a narrow piece of 
bottom land. . . . I remember seeing one on the up- 
land at the edge of a cornfield that I was cultivating. . . - 
I am sending you a skink today that I took this morning 
while I was digging in my dooryard.”’ 


The Inzards of Kansas 65 


Mr. Crevecoeur collected fifteen specimens of E. sep- 
tentrionalis about his home in 1926. It is of unusual 
interest that this lizard, so rarely taken elsewhere, should 
be found in such abundance in this one locality. 

Prof. Felix Nolte of St. Benedict’s College, Atchison, 
Atchison County, Kansas, has also kindly given the 
writer information about this lizard. He wrote on April 
22, 1926, that ‘‘A specimen collected about April 17 was 
brought into a house in the western part of the city (no 
woods near), by a common house cat.’’ The specimen was 


Cheyenne Rawlins Decatur | Norton Phillipe Smith Jewen | PePeblic |washington| Marshall | Nemabs —— 
Rene 
gor na “yh 
Cloud f. FREE 
Sherman Thomas { Sheridan | Graham | Rooks | Osborne | Mitchell Gros 
et 
Ottawa 
Lincoln Sha 
Wallace Logan Gove EE f Geary Sore 
‘Trego wis Russell tii: ee 
agemncree Dickinson cz 
Ellsworth Morria : 
Osage 
_——-} Pranidin}| Miami 
Greclay | Wichita} Scots | Lane Ness Rash Barton Lyon 
Rice MePherson! Marion Chase pees: 
Pawnee > 3.8 Me tna 
Bamition | Kearney —_—— Btafford ee Harvey eS teeyt 
Edwards Oreanwood [0 etre Bourtoa 
Sates ay tN 
Ford Sedgwick : 
Steaton | Grany | Haskell ae “ —————-| Wilson | Nevsho 
SSS cearaces 
ed gens 
Morton | Stevens | Sewsra | MO4* | Clark Comanche | Barber Harper | Sumner Cowley Labowe Shak 
Nat et 


Fig. 14. Distribution of E. septentrionalis in Kansas as indicated by 
e county reports. 


sent to the writer and when it was examined the teeth 
marks of the cat were still on the scales. The animal was 
alive and was kept in captivity for some time after it 
was received. On June 9, 1926, Prof. Nolte wrote an- 
other letter which explained that a second skink had been 
captured in precisely the same manner as the first. An 
examination of this specimen revealed a deep laceration 
in its back, 

The black banded skink feeds upon a large variety of 
small insects, 


66 Trans. Acad. Sct. of St. Lows 


Distribution in Kansas.—Eumeces septentrionalis is 
apparently an eastern Kansas form, and has not yet 
been found west of the distribution of E. fasciatus, with 
the range of which its known distribution in Kansas co- 
incides. The distribution indicates that it may be con- 
fined to moist grass land and woods. 


General Discussion. 

Of the species of lizards discussed in the preceding 
pages the following are regarded as established members 
of the Kansas faunal list. Except in the case of Humeces 
multivirgatus, specimens of each have been examined and 
identified by the writer: 1. Crotaphytus collaris (Say) ; 
2. Holbrookia maculata maculata (Girard) ; 3. Sceloporus 
undulatus thayerti (Baird and Girard); 4. S. widulatus 
undulatus (Latrielle); 5. Phrynosoma cornutum (Har- 
lan); 6. P. douglassti ornatissimum (Girard); 7. Ophi- 
saurus ventralis (Linné); 8. Cnemidophorus sexlineatus 
(Linné); 9. Letolopisma laterale (Say); 10. Eumeces 
anthracmus (Baird); 11. FE. fasciatus (Linné); 12. E. 
multivirgatus (Hallowell); 13. EZ. obsoletus (Baird and 
Girard); and 14, E. septentrionalis (Baird). 

The existence of data which might be made into Kan- 
sas reports for two species which are generically unre- 
lated to all lizards definitely reported from Kansas in 
the above pages, makes their consideration here a neces- 
sity. , 

Although Ellis and Henderson (1913) in their work on 
the ‘‘ Amphibia and Reptilia of Colorado’’ (p. 119), gave 
a table in which Dipso-saurus dorsalis was included 
among species recorded from Kansas, the writer’s ex- 
amination of over 1700 Kansas lizards has failed to re- 
veal any of these specimens. This is significant when 
one considers that so conspicuous a form as the keel- 
backed lizard could scarcely be long overlooked. In order 


The Lizards of Kansas 67 


to get a better understanding of this Kansas report a let- 
ter was written to Prof. Junius Henderson of the Univer- 
sity of Colorado, one of the co-authors of the work in 
which it was printed. Prof. Henderson replied on Septem- 
ber 14, 1926, that ‘‘ Although most of the records in that 
paper which were based on previous reports were fur- 
nished by me from the card index which I had prepared, 
the table was made by Dr. Ellis. I do not know where 
he obtained the Kansas record, as we have no specimens 
of the form from there or elsewhere, and I do not find 
any reference to the record in either our species index 
or Kansas index.’’ Another letter, asking for informa- 
tion concerning the basis of the report in question, 
promptly written to the co-author, Dr. Max M. Ellis, now 
of the University of Missouri, has as yet been neither 
returned nor answered. 


In short, it may be stated that the established range 
of the species has never included Kansas; the lizard is 
absent from Kansas collections; Prof. Henderson is un- 
able to substantiate the report; and Dr. Ellis has offered 
no objections to the questioning of his printed record. 
Therefore, it seems evident that the report was very 
probably a mistake, and that the species, Dipso-sawrus 
dorsalis, should not be regarded as belonging to the Kan- 
Sas fauna. 

Although there are various rumors concerning the dis- 
covery of the gila monster, Heloderma suspectwm, m 
Kansas, there is only one apparently authentic report of 
its capture in the state. A farmer, Mr. Gus Brune, Jr., 
Who lives seven miles northwest of Lawrence, Douglas 
County, is said to have captured a large specimen in his 
hay barn on September 26, 1924. The creature was ac- 
tive and free when taken. It was given to the Kansas 
University Museum by its captor, and remained there 


68 Trans. Acad. Scr. of St. Louis 


in captivity for some time. Finally it was killed and 
skinned. Its skin was preserved and is now a part of a 
fine collection of lizard skins kept at the Kansas Uni- 
versity Museum. 


The gila monster is the only poisonous lizard in the 
world, so far as is now known, and it is regarded with 
great concern in areas where it occurs. It is a brightly 
colored orange and black lizard of large size. It is so 
conspicuous a form that it would often be seen in Kansas 
if it normally occurred there. A theory has been advanced 
to explain the presence of the lizard in the hay barn men- 
tioned above. Since the barn is only a quarter of a mile 
from the Union Pacific railroad track, it is thought that 
the lizard must have been carried into the state by the 
train, and escaping from its place in some car, made its 
way to the point at which it was later found. That the 
gila monster, Heloderma suspectwm, does not normally 
occur in Kansas is accepted without question. <A dis- 
cussion of this lizard is included here only because of 
its special interest. 


The records which have given the following species 
position upon the Kansas faunal list are regarded as 
very questionable, and the present data indicate that 
they are not to be considered as inhabitants of the Kan- 
sas area. 1. Dipso-saurus dorsalis (Baird and Girard) ; 
2. Holbrookia maculata lacerata (Cope) ; 3. Phrynosoma 
brevirostre (Girard); 4. P. douglass hernandesi (Gir- 
ard); 5. Cnemidophorus gularis (Baird and Girard) ; 
6. C. tessellatus (Say); and 7. Heloderma suspectum 
Cope. 


From the standpoint of animal dispersal Kansas oc- 
cupies a unique position. Adams (1902) has stated that 


The Inzards of Kansas 69 


there have been two great centers of biological dispersal 
for the United States. They are the ‘‘Southeast and the 
Southwest, the former moist, the latter arid.’? Ruthven 
(1908) wrote that ‘‘Most of the forms which inhabit the 
prairie region either extend into the eastern forest re- 
gion or into the plains region, or rarely both, few being 
confined to the prairie region. . . . There is a great 
difference in the extent to which the forms of eastern 
North America push westward, or the plains forms push 
eastward into the prairie region before becoming modi- 
fied or checked.’’ Thus it is found that dispersal after 
the glacial period has been from the southeast and south- 
west toward the central region of the United States in 
which Kansas is located. Since the two regions are op- 
posed to each other, the line of their meeting must be 
somewhere in the central region, the distribution of each 
Species being limited by its ability to withstand condi- 
tions more typical of its opposite region of dispersal, 
and less typical of its own region. The difference in the 
extent of the toleration of each species for the opposite 
region varies, as data on Kansas lizards show, and no 
distinct line can be drawn to mark the point at which 
the species with their center of distribution in the east- 
ern region cease to exist and where the species with their 
center of distribution in the western region begin to ap- 
pear. Thus, at the line of meeting there is an overlap- 
ping between the two groups, and it is in such a region 
that the factors limiting distribution are to be sought. 
If moisture were uniform at the point and temperature 
varied, temperature would be a controlling factor. If 
the formations of the area were geologically varied some 
of them would probably be preferred by certain lizards 
and some by others. Pearse (1926) has stated that ‘‘The 
distribution of animals often has direct relation to the 


70 Trans. Acad. Sci. of St. Lows 


availibility of food, and particular foods are:the leading 
factors in the lives of many animals.’’ Most lizards are 
predaceous and take live foods, and since that is true, 
it is evident that factors which influence the distribution 
of the prey of the lizard, more or less directly, influence 
its own distribution. It is evident that the problems 
arising in such a region are both extremely complex and 
interesting. 


Kennedy (1917), considering the general surface of 
the land, rather than its extremely varied texture, has 
written that ‘‘Topographically Kansas presents little 
that is not monotonous. The eastern third of the state 
is a region of low hills, and meandering, muddy streams. 
The western two-thirds is an upland plain. The surface 
of the state rises gradually from 800 feet elevation in 
eastern counties to 3600 feet in Greeley County on the 
extreme western border of the state.’’ The rise in eleva- 
tion in the eastern half of Kansas is only about 700 feet, 
whereas the rise in the western half of the state is over 
2000 feet. From this it is evident that Kansas is lower 
and flatter in the east than in the west. The topography 
of the eastern part of the state consists of rolling prairies 
broken frequently by wooded streams. Beginning at 
about the 1500 feet contour there is a rise to a treeless 
plein in the west. It is at this contour, theoretically, 
that the eastern and western regions meet. This is the 
place where the woods become sparser, and the rolling 
prairie extends onward. The above distributional maps 
show it to be a critical region in animal dispersal. 


Precipitation, according to the Weather Bureau, 
United States Department of Agriculture (1923) de- 
creases with remarkable uniformity from 42 inches in 
the southeastern counties to a little more than fifteen 


The Inzards of Kansas 71 


inches at the western boundary. The northern half re- 
ceives practically the same amount of rainfall as the 
southern. The eastern part of the state thus presents a 
much more humid surface soil than the western part of 
the state, another factor that has a profound influence 
upon lizard dispersal. 


Only three of the fourteen established species of Kan- 
sas lizards have a state wide distribution. Cnemido- 
phorus sealineatus is one of the most widely distributed 
lizards in both the United States and Kansas. It is com- 
mon to both eastern and central faunal lists. Phrynosoma 
cornutum and E'umeces obsoletus are also state wide in 
their distribution, but have come from the southwest be- 
yond the plains of Kansas. Hurter (1911) reported only 
P. cornutum from Missouri, and Hurter and Strecker 
(1909) reported neither species from Arkansas. 


Crotaphytus collaris occurs both to the east and to the 
west of Kansas. Its center of distribution is decidedly 
in the west, California being on the western line of its 
dispersal and Missouri on the eastern. Its distribution 
in Kansas is peculiar since it has been reported from 
only the eastern two-thirds of the state. 


The skinks, Eumeces septentrionalis and E. multivir- 
gatus, have their center of distribution in the ‘‘central 
area’’ and do not occur far to the east or west of Kansas. 
The former is a north central form, and the latter a 
south central form, Kansas lying in the pathway of the 
distribution of each, and possibly being the southern 
boundary of the range of E. septentrionalis, since Orten- 
burger (1926 a-b-e) did not report it from Oklahoma. 

€ nine species of lizards that are left, counting again 
Ewmeces obsoletus, which has not been found east of 
Kansas, fall into two nearly equal groups and are listed 


72 Trans. Acad. Sci. of St. Louis 


below according to their known distribution. In no case 
has the writer found an authentic report of a western 
form east of Kansas, or an eastern form west of it, and 
in all cases the known reports in Kansas, with the ex- 
ceptions of Crotaphytus collaris and Ewmeces obsoletus, 
clearly indicate each species to be either eastern or west- 
ern in its center of distribution as a glance at the maps 
will show. 


The four species with their present centers of distribu- 
tion in the southwest are Sceloporus undulatus thayeru, 
Holbrookia maculata maculata, Phrynosoma douglassu 
ornatissimum, and Eumeces obsoletus. 

The remaining five species, which have apparently 
come from the southeast are Sceloporus undulatus un- 
dulatus, Ophisaurus ventralis, Leiolopisma laterale, 
Eumeces anthracinus and E. fasciatus. 


Lizards occur in varying abundance in Kansas both 
as species, and as representatives of genera and fam- 
ilies. The families Iguanidae and Scincidae are repre- 
sented on the state faunal list by six species each, both 
being rich in multiplicity of forms, whereas the families 
Anguidae and Telidae are represented in Kansas by one 
species each. Phrynosoma cornutum is a species which 
has always been taken singly in Riley County, according 
to the records, but nine specimens were collected in one 
afternoon in Ottawa County and more were observed. 
It is not easy to classify lizards as to abundance, though 
some are distinctly rare species and others are very com- 
mon. The following table classifies Kansas lizards by 
species according to the extent of their appearance in 
collected material, and gives a rough index to their rela- 
tive abundance in the state, since common lizards are 
taken oftener than rare ones. 


The Lizards of Kansas 73 


Table of Kansas Lizards. 


Number of Speci- 
Species mensinCollec- Per Cent 
tions Examined of Total 
Crotaphytus collaris 400 22.52 
Eumeces obsoletus 280 15.73 
Holbrookia maculata maculata__- 215 12.07 
Sceloporus undulatus thayerii_-- 190 10.67 
Cnemidophorus sexlineatus -__-- 185 10.39 
Phrynosoma cornutum __------- 145 8.14 
Eumeces fasciatus 120 6.74 
Ophisaurus ventralis 80 4,49 
Leiolopisma laterale 55 3.09 
Eumeces septentrionalis -------- 42 2.35 

Phrynosoma douglassii ornatisst- 

mum 40 2.24 
Ewmeces anthracinus 18 1.01 
Sceloporus undulatus undulatus_- 7 0.39 
Eumeces multivirgatus (See p. 57) 3 0.17 
Total 1700 100.00 


The five lizards at the top of the list are certainly very 
abundant where they occur in Kansas. The eighth, 
Ophisauris ventralis, is not, however, abundant in the 
Same sense, and more than a few specimens of this lizard 
are seldom taken at once. Yet, because of its widespread 
distribution in eastern Kansas and its occurrence near 
both the Kansas State Agricultural College and Kansas 
University where much of the collecting of Kansas 
lizards has been done, it is represented in Kansas muse- 
ums in fairly large numbers. Leiolopisma laterale has not 
yet been found to be abundant in Kansas, with the ex- 
ception of Franklin County, and usually only one or two 
Specimens are taken at a place. On the other hand, the 
much rarer species, Eumeces septentrionalis, has been 


74 Trans. Acad. Sct. of St. Lows 


found to be very abundant at Onaga, Pottawatomie 

County, Kansas. Sceloporus undulatus undulatus is a 

rare Kansas lizard, but Mr. W. H. Burt has reported it 

as being abundant on a bluff of Shoal Creek, Cherokee 

County, where it was ‘‘very hard to capture.’’ 

Interature Cited. 

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The Lizards of Kansas 75 


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76 Trans. Acad. Sci. of St. Louis 


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The Inzards of Kansas 77 


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78 Trans. Acad. Sci. of St. Louis 


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The Lizards of Kansas 79 


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80 Trans. Acad. Scr. of St. Lows 


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The Lazards of Kansas 81 


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INDEX 


Alligator lizard 20 
Anguidae Pe 
Aatiiacits skink 49 
Black banded skink 63 
Black lizard 19 
Black shouldered lizard 6 
Black skink 49, 58 
Blue-spotted skin 58 
**Blue-tail skink 2 Kansas’’ 59 
Blue-tailed skink 51 
Brown backed lizard 45 
Brown scorpion 20 
Bull lizard 6 
Bull snake 61 
Cactus lizard : 
r 
sain ete se 38, 40, 41, 68 
sexlineatus— 
4,16, 38, 40, 41, 43, 44, 45, 46, 54, 61, 4 66, 71, 73 
tessellatus 40, 41, 68 
al 49 
Collared lizard 6 
ommon gray skink 58 
Common horned toad 27 
Crotaphytus collaris 2, 5, 10, 11, 60, 66, 71, 72, 73 
atleyt 7 
collaris . 
ee sarus dorsalis 66, 67, ss 
aste + 
Eum we il ies "3, 5, 50, 51, 54 
anthracinus 5, 49, 50, 51, 52, 66, oe 73 
epipleurotus 
secksteale 5, 51, 54, 55, 56, er . 72, : 
guttulatus 9, 62, ie 
a Te 
ngirostris sicinaiaiel A 
multivirgatus 5, 56, 57, 58, 66, 71, 73 
obsoletus 5, 45, 56, 58, 60, 62 63, 66, 71, 72, 73 
ptibialig SS eh. DE 
Septentrionalis 5, 58, 63, 65, 66, 71, 73 
Fence lizard ae 
Five-lined skin ee BE 
Gila monster _ LO «7 | 
te short-horned lizard nn oe 


Gray Nellie 6 


Gray skink 58 
Grass snake 36 
Ground lizard 
Hallowell’s skink 56 
Hayden’s skink 56 
Heloderma suspectum 67, 68 
Holbrookia 13 
maculata 13 
lacerata 18, 14, 68 
MACULAE eveneannn- * S24, 12. 33,14, 36, 49... 46, 66, 72, 73 
Holbrook’s sand swi 11 
snake 36 
Horned lizard 27, 32 
Horned toad 27, 32 
Iguanidae 4, 72 
Joint lizard 36 
Joint snake 36 
Keel-backed lizard a 
Lamprosaurus guttulatus 59 
Leiolopisma laterale ..........5, 45, 46, 48, 49, 54, 60, 66, 72, 73 
Little white-spotted skink 58 
Lygosoma laterale 46 
Many-lined skink 56 
Mountain boomer 6 
Northern skink 63 
Ophisaurus ventralis 4, 36, 39, 66, 72, 73 
Ornamented horned lizard 32 
Ornate horned lizard $2 
Phrynosoma oo 30 
brevirostre 3, 68 
cornutum © .......5, 27,28, 29, 20, 81. 82, 66, 71, we 73 
douglassit 34 
hernandesi. ...... 33, 34, 36, 38 
ornatissimum ...........5, 32, 33, 34, 35, 36, 66, 72, 73 
hernandesi mn 
Pine lizard ae 
Pine tree lizard .. 20 
Pituophis sayi — 
seen obsoletum ..... a 
e-horse pa 
Han ae 38 
Race-runner Sa 
Red headed lizard 2 BE 
Sand scraper ee 
_ Sand snake ee 


Sceloporus Tae «| 
consobrinus Te Wf 
consobrinus 17 
spinosus 25 
thayerii 16, 17 
undulatus 20, 21, 23, 25 
consobrinus 17 
thayerti , 16, 19, 20, 21, 22, 26, 27, 45, 66. 72, 7 
undulatus.. 5, 19, 20, 21, 2, 24, 26, 27, 66, 72, 73, 74 
Scincidae 4, 72 
Scincus erythrocephalus 53 
lateralis 46 
unicolor 46 
Scorpion 51 
i 49, 51, 56, 58, 63 
Six-lined lizar 38 
Six-lined race-runner 38 
Six-lined s 38 
Six-lined whip-tailed lizard 38 
Snake wa OE 
Sonoran skink 58 
Spiny eee horned lizard im ot 
piny gs 16, 19 
Spotted Ii ead -~il 
Stellio undulatus 20 
Striped lizard . 51 
Striped spiny swift . 16 
ks See 1), 16, 19, 7 
Tantilla rac - 
Teiidae si = 4, 72 
Texas tonal lizard cig at 
Thayer’s alligator lizard — 16 
Tree lizard eee AO 
Western skink ne OB 
Whip-tailed lizard - 38 
White-spotted skink —_—-— 58 
Yellow-banded swift een 1G 


Transactions of the Academy of Science of St. Louis 


Al 


Volume XXVI, No. 2 


. THE SEX ATTRACTION 
AND RHYTHMIC PERIODICITY IN 
GIANT SATURNIID MOTHS 


Phil Rau 
and 
Nellie L. Rau 


Benes be ef 
of i 


ee cs : 
LIS 


w4 
Mi 
te 


Pi 


k : ‘ i Zi \ ° e 
wo ES Eh eae 
NES ae Pry Py ae 
Meas ai: ae ee sep 
ERS, 1929 
: ke ss oo gale 
Pas: AD BAD cue f 


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4S : , BE AACS 9 
ms hy 

Be? ps 


ay 


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om 3 i 
Id 


Fig. 1. Arrangement of cages on roof. 


The Sex Attraction and Rhythmic Periodicity in the 


Giant Saturniid Moths 


Phil Rau and Nellie Rau 
CONTENTS 


Part I. 


Mumerustion 
emoreal Resumé. es 
fee Voptial Viight ee 
Experiments on Samia Cecropidrriccccooe coe 00 wee soon 
Experiments on Platysamia cynthide.o....--0-0---- 
Experiments on Telea polyphemus.....-. 000 
Experiments on Callosamia promethed......0.000---—— 


Part II. 


Experimental Studies on Odor, Wind and Light in rela- 
tion to Rhythmic Periodicity in Saturniid Moths. 

inboduction-... ee 
Experiments to Test Perception of Odor (Cecropia)..... 
Electrie Fan Experiments... rn 
Experiments to Test Reaction to Light... 
Activity in a Dark Boor nccccc ccc cee 
Relation of Movement of Male Cecropias and Poly- 


Phemus to Moonlight... ----_-0 nn 
Thermotropism ... Seeger = Se 
Normal keane = es 


Rhythmie Periodicity of Platysamia ODS, 
Experiments on Cecropia and Polyphemus in Relation 
@ light 
The Light of Dawn... 
Final § Summary 
Discussion of Rhythmic ‘Periotielig. BORE oO 


“With their tropisms, their rhythms, the adaptive manifesta- 
lions of their differential sensibility—above all with their power 
of transforming habits into automatic actions—the articulates 
are essentially animals of instinct whose activities consist prin- 
cipally of automatisms, but automatisms dominated by cerebral 
power, One can hardly see in them ‘simple reflex machines’, 
for they know how to bend to circumstances, to acquire new 
habits, to learn and to retain, to show discernment. They are, 
one can say, somnambulists, whose minds awaken to give proof 
of intellect when there is need for it.”-—E. L. BOUVIER. 


“‘Instinct precedes intelligence both in ontogeny and phylog- 
eny, and it has furnished all the structural foundations employed 
by intelligence. * * * Since instinct supplied at least the earlier 
rudiments of brain and nerve, since instinct and mind work with 
the same mechanisms and in the same channels, and since 
imstinctive action is GRADUALLY superseded by intelligent 
action, we = compelled to regard instinct as the actual germ 
of mind. 


“‘We are apt to contrast the extremes of instinct and intelli- 
gence—to emphasize the blindness and inflexibility of the one 
and the consciousness of the other. It is like contrasting the 
extremes of light and dark and forgetting all the transitional 
degrees of twilight. * * * Instinct is blind; so is the highest 
human wisdom blind. The distinction is one of degree. There 
is no absolute blindness on the one side and no absolute wisdom 
on the other. Instinct is a dim sphere of light, but its dimness 
and outer boundary are certainly variable; intelligence 1s 0 
the same dimness improved in various degrees. * * * Intelli- 
gence implies varying degrees of freedom of choice, but never 
complete emancipation from automatism. The fundamental 
identity of instincts and intelligence is shown in their depend- 
ence upon the same structural mechanism and in their responswe — 
adaptability.”’—C. O. WHITMAN. 


PART I. 
INTRODUCTION. 


Night ever draws a veil of mystery about the things which 
belong to her domain. Although childhood’s fear of the dark 
may have been explained away, yet the feeling lingers that in 
the realm of Luna we may expect something of the weird. Per- 
haps this, but more probably our love of undisturbed slumber, 
has led to an excess of fancies but a deplorable dearth of re- 
liable information concerning the activities of these interesting 
denizens of our woods, the giant Saturniid moths. 

Several years ago a well-known entomologist fascinated me 
with the story of how he had observed the males of the Saturniid 
moths ‘‘fly great distances up hill against the wind to reach the 
females.”? ‘‘How far,’’ thought I, ‘‘can they actually travel, 
and what directs them there?’’ The question caught my fancy, 
and during the intervening years I have often thought of this 
“‘romantie’’ behavior. Often I was tantalized by seeing in the 
literature some Meager references to this phenomenon, but 
While some authors suggested theories as to the guiding stimulus, 
hone offered any experimental evidence as proof of any theory. 
Finally, bent upon an attempt to solve these problems of the sex 
life of the giant Saturniids, or more precisely stated, a study of 
how far the males can travel to reach the females, and what 
mechanical or psychical factors influence their reactions, I ob- 
tained a large number of cocoons of four species of these moths, 
to add to our native population here, and made detailed observ- 
ations throughout the season. 

The work was all done from the third story window and on 
the second story roof of the rear of the house, which could be 
reached from said third story window, of a city dwelling (fig. 2 
shows a portion of this roof and view toward the west). At the 
Windows and on the roof, from time to time, wire cages rsicagaal 
mg the female moths were placed. Then, taking a position of 
watchfulness, net in hand, I kept vigil through a greater part 
of the night, every night, from May 7 to June 27, a period of 
fifty-two days, which is the duration of the natural season for 
these species. Hach moth was numbered, in oil paint, on the 
Wings, and individual records kept of the age and activities of 


84 - Trans. Acad. Sct. of St. Lowis 


each of the 1477 bred moths, and of the arrival and activities 
of each of the 1249 wild moths; thus the study comprises the 
individual records of 2726 moths. 


While the problem involved many real difficulties and compli- 
cations, yet the material held certain unusual advantages for 
such experimentation. These moths are easily handled, and have 
wings sufficiently large on which to paint distinguishing marks, 
so that accurate records may be kept of each individual. They 
require no food in the adult stage, so all adverse conditions aris- 
ing from improper food are eliminated. By breeding the speci- 
mens from cocoons, accurate data may be had as to the age of 
the moths, and the factor of age in influencing their responses. 


While this material came from Long Island, New York, three 
of the species, Samia cecropia, Telea polyphemus and Callosamia 
promethea, are natives of Missouri also. The fourth species, 
Platysamia cynthia, is not native of Missouri, but is abundant 
in the Atlantic States. Hence, in experimenting with the first 
three species, one had to contend with interference, sometimes 
favorable and sometimes troublesome, of the wild population 
hereabouts, but in handling the cynthias, we were certain that 
our imported stock constituted the entire population, although 
in some cases there was reason to believe that some of these 
moths responded slightly to the attraction of the females of the 
other species, and may thus have reduced the otherwise high 
percentage of returns. 

The experiments could not be carried on just as they were 
planned ; because of unexpected difficulties one could only take 
what material was at hand, quickly plan an experiment and 
execute it in the best way the conditions afforded. This factor 
may give the work a tone of not having been carefully planned. 
The difficulties were, of course, that often when one needed 
females, only males would emerge, and vice versa, and often 8 — 
shifting of the wind, a change in the weather, and urban crowds, 
caused a change in a contemplated experiment. Extensive work, 
attempted two years later,* for the purpose of getting records of 
five-mile flights outside the city had to be abandoned because of 
the depradations of birds. Screech-owls devoured the incoming — 
night fliers, and by day the sparrows, blue-jays and woodpeckers 


*At Kirkwood, Mo. 


Introduction 85 


attacked the prometheas in midair; in the morning the lawn was 
strewn with illegible, numbered wings. 

Each experiment is a unit in itself, and is given as such. It 
was at first my intention to reduce the work to tables, and thus 
greatly shorten the text, but so many factors are involved in 
each and every experiment which would be lost in tabulation 
that it seems best to preserve these significant details. 


HISTORICAL RESUME. 


Everyone knows, in a vague way, that moths are nocturnal 
and butterflies are diurnal. While I can think of no instance of 
butterflies flying by night, we do know that some of the moths 
fly during the day. 

There are few records on the actual hour of flight of moths 
of the family Saturniidae. To solve some of the problems of 

their flights it is not enough merely to know that the moths are 

active at night; it is necessary to know at what hour they fare 
forth. We have brought together here some of the chief items 
of information available in the literature. 

Soule and Elliott! tell us that the promethea moth flies any 
time after two in the afternoon. Once a female at the window 
attracted forty males. Cecropia moths will fly near electric 
lights, and may be found under shed roofs by day, and may be 
tracked to their hiding places by their strong odor, especially 
strong in the females. 

Possibly the most purposeful study of the sex activities in 
moths is that of A. G. Mayer He gives the results of experi- 
ments carried on in Florida upon material brought from Massa- 
chusetts. He finds that males are attracted to females not by 
Sense of sight but by odor. A male will fly to a female even if 
his entire abdomen is cut away, and he will seek a female even 
when his abdomen is cut off and the sides of his thorax covered 
with impervious glue. From this he concludes that the spiracles 
are not the seat of the organs by which the male perceives the 
female scent. If the antennae are covered with glue, shellac, 
paraffin, photographie paste, ete., the moth no longer seeks the 
female, and will display no excitement, even though he be placed 


1Caterpillars and Their Moths. 
*Psyche, 9: 15-20. 1900. 


86 Trans. Acad. Sct. of St. Louis 


within an inch of her. When the photographic paste is dis- 
solved off in water, mating readily occurs. He also finds that 
blinding the males does not deter them from finding and mating 
with the females. 

Fabre® writes quite spiritedly of the hordes of males that 
came to a captive female peacock moth. For a week they came 
to her each evening, between 8 and 10 o’clock. The first evening 
forty males arrived, and on another evening twenty-five came. 
Two years later he also got large numbers to come to his captive 
females which he moved about the house occasionally but did not 
succeed in deterring the males. He removed the antennae of 
some of these males, and his results and conclusions will be dis- 
cussed later. 

Fabre also experimented on a day-flying moth, the lesser pea- 
cock, Attacus pavenia minor Linn. From high noon until two 
o’clock each day for a week, the males came to the captive fe- 
male, ten the first day and a total of forty for the week. He also 
observed that the moth known as the banded monk or oak-eggar 
attracted males from great distances at 3 o’clock in the after- 
noon in ‘‘very hot weather and brilliant sunshine,’’ ‘‘coming 
from over the walls, over the curtain of cypress trees. The room 
is filled with a swarm of sixty males, keeping up their frenzied 
movements for three hours.’’ With the banded monk he ex- 
perimented by placing the females in loosely-put-together recep- 
tacles and in receptacles hermetically sealed. He found that the 
males discovered the females only in the loosely constructed 
receptacles, and not in the air-tight ones. He made tests also 
with a second species of monk moth, the clover Bombyx, nearly 
akin to the first, and plentiful about his home. He placed six 
females in cages, but not one male appeared. 

Forel* says that a large swarm of Saturnia carpini came to 
his room in the city where he imprisoned females. The swarm 
of males that came outside to besiege his window was such that 
it attracted a crowd of ragamuffins in the street to catch the 
beautiful insects. 

Kellog® gives us some valuable data on the silk-worm, Bomby2 
mori. He says the female moth, nearly immovable, protrudes 4 

~ 8The a = the Caterpillar, Chap. XI. 1916. 


4Senses of Insects, p. 76. 
5Biol. a: 12:152. 1907. 


Historical Resumé 87 


paired scent organ from the hindmost abdominal segment, and 
the male walking nervously about and fluttering its useless wings 
soon finds the female by virtue of its chemotactic response to 
the emanating odor. Blind males find the females, but those 
with the antennae removed do not. If the female scent glands 
are cut off and put wholly apart from the female, the males are 
as strongly attracted to these isolated glands as they are to the 
unmated females. Males try persistently to mate with the iso- 
lated scent glands. Males mated with headless females and with 
females with the head and thorax off. Removing the left or 
right antenna of males caused them to move in repeated circles 
about the female, to the right if the left antenna was removed, 
and to the left if the right one was missing. 

Duges® cut the antennae of two male (Bombyx) Endea 
pavonia minor and these insects were unable to find a female 
which they had previously been able to locate. Trouvelot per- 
formed various experiments on butterflies and on the promethea 
moth; he concludes that the antennae are the organs of smell. 
He regards it as a kind of feeling or smelling at a great distance 

Y some process now entirely unknown. 

Kirkland’ experimented upon the moth Prothetria dispar, and 
found that the males were attracted to their mates solely by the 
odor of the females. He also found that the severed wings of 
the females were highly attractive to the males. 

Mayer, and Soule ® conclude that it is not associative memory, 
but chemotaxis that attracts the males to the females of both 
Callosamia promethea and Porthetria dispar. They covered the 
antennae of the males with flour paste, and the moths did not 
again mate. In many instances, however, they did so immedi- 
ately after the flour paste was dissolved away with~water. In 
this same work the authors found that if the wind was allowed 
to blow from a female toward a male Saturniid moth of the 
same species, the male might be induced to mate with a female of 
another species confined in a eage with him. : 

Riley® liberated a male cynthia moth in the park a mile and a 
half from a female in his window. The next morning the two were 
63: 1-63. 1914. 

$:429. ‘ 


. Coll. 
SQuoted by McIndoo, Smithson. a mere 1906 


TQuoted by Mayer and Soule, Jour. I. 
8Jour. Exp. Zool. 31:429. 1906. 
"Insect Life 7:38-40. 1894. 


88 Trans. Acad. Sct. of St. Louis 


together. Riley was much impressed by the attraction of insects 
for one another from a distance, and he tried to account for it 
by what is known in man as telepathy, for he says: ‘‘this power 
would depend neither upon scent nor upon hearing in the ordi- 
nary understanding of these senses, but rather on certain subtle 
vibrations as difficult for us to apprehend as is the exact nature 
of electricity.”’ 

Rau’ describes the courtship of Telea polyphemus and says 
that during sexual excitement the antennae of the males are 
erect and alert, while on other occasions they are drooping and 
limp. 

Soule" concludes from observations on cecropia, promethea 
and angulifera that there is some emanation from the ovipositor 
which attracts the male. The female protrudes the whole ovi- 
positor which excites the males, and no male will mate or ap- 
proach the female without being attracted in this way. 

Hamm” while collecting Lepidoptera carried a bag in which 
a week previously he had confined a moth of Bombyx quercus. 
Several males of this species were attracted to this bag, and he 
attributed the attraction to the scent of the female still retained 
in the bag. 

Von Dalla Torre™ says the females of many Lepidoptera give 
out perceptible odors to the male and thereby induce copulation. 
It seems proven that by extending the ovipositor the female can 
cause the dissemination of odor which attracts the male. 

Hauser" finds that Saturnia pavonia never makes an attempt 
to mate when the antennae are off. 

Rau shows that the female moths as well as the males dis- 
play much emotion at mating time. When a male is introduced 
into the cage, the female often protrudes the ovipositor and 
gently or nervously moves the wings, thereby disseminating the 
odor, and brings him to great excitement. She sometimes chases 
him about the cage. 

Fritz Mueller'® says the males of many hawk moths can scent 

10Canad. Ent. 56:271. 1924. 
pant 9: a 1901. 
12Ent. Monthly Mag. 6: =. Ag 1895. 
18Quoted by y Meotndeo, loc, ci 
by Mayer and Soule, Psyche, 9:19. 1900. 
. Acad. Sci. St. Louis, 20: 275-319. 19 
Butterfly Hunting in Many Eandn 1912. 


Historical Resumé 89 


the virgin females from incredible distances, and it has long 
been known that the privet and convulvulus hawk moths, espe- 
cially during flight, diffuse a strong, musty scent. The males 
of a moth of the genus Cryptolechia and those of the 
Glaucopidae exsert from the apex of the abdomen two long, 
hollow filaments, from which proceeds a scent which is often 
very powerful to man. Similarly with the South American 
butterflies, the gigantic Morphos, the males extrude from each 
side of the apex of the abdomen a hairy, strong-smelling gland, 
of which the scent in M. adonis and M. cytheris resembles 
vanilla. In an interesting series of papers translated in this work, 
Mueller gives valuable information on the odor emitted by vari- 
ous species of Lepidoptera, and the precise location of the scent- 
bearing apparatus. On the relation of odor to sex attraction, 
he gives only the above information. 


THE NUPTIAL FLIGHT. 
Experiments on Samia cecropia. 


Exp. 1. May 7. Two females emerged prematurely and for 
the past few days have been at the open window. This morning 
when I entered the laboratory I found that three young native 
ceropia males had come during the night and were quietly at 
rest on the window sash. Thus at the very beginning, the intru- 
sion of the wild stock with the bred material complicated the 
observations. 

Exp. 2. May 7. Wind, south-west; station, 225 yards east. 
Two of the native males that had appeared in Exp. 1 and a bred 
male 24 hours old, each with its distinguishing mark of paint, 
were liberated at 6:30 p. m., in the park, directly in front of 
the house; the caged females were on the window-sill. The air 
was humid from a shower that had just passed; the wind blew 
through the house, and there was a chance that it might dis- 
seminate to a point near to where these males were liberated. 
One hour and twenty minutes later, the bred male, one day old, 
came fluttering to the cages containing the females; no others 
returned. 

Exp. 3. May 7. Wind, south-west; station, 225 yards west. 
The young male that had just returned in Exp. 2, was liberated 
at 8:05 p. m., of the same day, the same distance to the rear of 
the house, where the wind could not possibly waft the odors from 
our caged specimens. This moth did not return this time. 

Exp. 4. May 7. Wind, earlier in the evening, had been 
south-west, now imperceptible; station, 225 yards east. Male 9 
had emerged May 5, mated 714 hours later, severed May 6, at 
noon; 30 hours later he was very active, and was liberated in 
the park at 9 p.m. The conditions were the same as in Exp. 2, 
excepting that the wind had fallen and this male had already 
mated. The temperature in the room was 68° F., while outside 
it was 59° F. After 40 minutes, he flew in the window and 
passionately fluttered about the cage; he did not stop at the 
cage in the window, but flew past it into the room and ho 
about the younger female on the table. 

Exp. 5. May 7. Wind, same; station, 1% mile east. This | 
male which had just returned was taken out for a longer dit. = 


The Nuptial Flight 91 


tance in the same direction, and liberated at 10:15; at 11:25 it 
returned again. The temperature was now falling; the large 
number of park lights which the moth had to pass seemed to 
exert no disconcerting influence. 

Exp. 6. May 7. Wind, same; station, 11/6 mile east. Once 
more this weary moth was taken out to a more distant point 
in the same direction, and liberated at 11:50 p. m., but it never 
came back. The temperature fell low that night, with rain and 
Snow, so we must abandon the experiment without knowing 
Whether exhaustion, lack of odor perception, adverse weather 
conditions or the presence of some other female elsewhere caused 
the failure of this moth to return. Later tests proved that both 
rain storms and greater distances than this may be surmounted 
by these creatures. 

Exp. 7. May 14. Four females of various ages had been 
kept at the windows for several days, and this morning 7 young 
native males were found in the room. 

Exp. 8. May 15. While the east windows were closed, 12 
native males flew in during the night through the west windows. 
However, they did not remain in the west room, but moved to 
the east room, probably attracted by the light rays of dawn 
more than by the odor of the females, for all were at rest on 
the window sash, instead of the cages on the table. Judging 
from the perfect condition of the wings, all were quite young. 

Exp. 9. May 16. Since May 14 and 15 had given us 19 
wild males, and I was in need of more material, I made special 
effort to get them by opening all the windows and placing to 
advantage (in relation to wind) my best females. But none 
came during that night. This inactivity may well be attributed 
to the low temperature, which was only 50° F., between 1 and 4 
a.m. We know from earlier investigations* that a low tem- 
Perature retards the activity of these creatures and, by conserv- 
ing their stored energy, which cannot be replaced, prolongs their 

ife. Heavy rains and thunderstorms oceurred during the night 

also, but on other oceasions these elements did not deter the 
a in their flights when temperature conditions were favor- 
able. 

Exp. 10. May 17. With the thermometer fluctuating be- 
—— ones 


“Trans. Acad. Sci. St. Louis. 23: No. 1, 1914. 


92 Trans. Acad. Sct. of St. Louis 


tween 50 and 55 during the night, only two native males flew in 
at the window. 

Exp. 11. May 17. Wind, south until 7 p. m., then shifted 
to east ; station, 250 yards east. The two native males which had 
come in during the night, and two bred males, aged 44 hours 
and 6 days respectively, were liberated in the park east of the 
house at 6:30 p. m. None of these moths returned that night, 
but three mornings later the youngest one was with native males 
that flew to the laboratory. It would be interesting, indeed, to 
know where and how he at last ‘‘hit the trail.’’ 


Exp. 12. The night of May 17-18 was chill and stormy; the 
temperature was about 56°, and almost an inch of rain fell be- 
tween 7 p. m. and 7 a. m., while a strong wind blew from the 
east, through the upstairs windows. The two laboratory rooms 
had five windows, two opening directly to the east and three to 
the west. The two eastern windows contained 7 cecropia and 3 
polyphemus females, and the western windows had 4 cecropia 
(1 dead) and 3 polyphemus females; all these had been in this 
position for two days, giving ample exposure for the dissemina- 
tion of odors or any other means of communication which he- 
trayed their presence. But the two nights preceding had brought 
in none, and even the cocoons on hand were yielding no moths; 
the beating rain foretold disappointment again, so, being dead 
for sleep, I retired at midnight. 

At 4 a. m. I was startled awake by the beating of wings on 
the window-shade in my second floor bedroom, and the rasping 
rustle of many wings in the laboratory. Going to the third floor, 
three steps at a jump, I was met by dozens of excited cecropias 
flying about the cages on the west windows, and looking out I 
saw many more fluttering in my direction and making their way 
erookedly to the windows, all through the pouring rain. The 
females in the cages, heretofore always sluggishly quiet, showed 
great agitation, beating their wings against their cages. This 
shows that the females, too, join in the activity, or, as later ex- 
periments will show, by flapping their wings they disseminate the 
odor from their bodies. Excitement ran high as other members 
of the family, brought thither by their curiosity regarding the 
unwonted commotion at such an hour, forgot their sleepiness — 


The Nuptial Flight 93 


and joined in the impromptu ghost-dance in an effort to capture 
the many giant moths that were fluttering and darting like bats 
about the ceiling and walls of the rooms. When, at last, the 
moths had ceased to come in and had all been gathered into 
cages, it was found that 42 had come in during this brief period. 
Standing on my roof as daylight was breaking over smoky St. 
Louis, and viewing my trophies in the cages, I ean truly parody 
Emerson: 

A second crop thy roof-tops yield 

Which I garner in a yawn. 


With these made safe, I could then calmly make records of 
the many interesting details which had been crowded into that 
brief period. This great movement of the moths had occurred 
just as day was breaking, at a little before 4 a. m.; by 4:30, they 
had entirely ceased to come in, and more than that, the moths in 
the cages had all subsided to quiet, and rested motionless. This 
was my first intimation that their activity is probably strongly 
Periodical; henceforth I was always on guard to discover the 
factors controling this periodicity. 

It was unquestionably evident, as I watched them coming in, 
that all of these males came from the west, flying against the 
Wind. Not one of them flew to the east windows, where other 
females were in cages, neither did any of them fly over the 
housetop and retrace its flight. It seemed that the strong east 
Wind blowing through the house must have carried the odors out 
through the west windows, and the males, following it back, 
tame to the west windows instead of the east ones. Unless we 
consider this hypothesis, there is ample reason to expect more 
Moths to come from the east than from the west, because the 
area to the west was closely built up with dwellings and indus- 
tries, while to the east lay a large park. It seems to me that, 
even if no other tests were made, this one experiment would be 
Sufficient to demonstrate conclusively that wind is a factor pe 
bringing the males to the females. This is quite unlike Fabre’s 
observations of Attacus pavonia minor, which, he says, came 
With the wind. The seven females in the east windows attracted 
nO suitors from without, but the four (one of which was dead) 
in the west windows drew the mob. Surely, had factors other 


ee, 
*Social Life in the Insect World, p. 197. 1912. 


94 Trans. Acad. Sct. of St. Louis 


than the wind brought the message to the males, as Fabre thinks, 
then a fair proportion of them, at least, would have come in with 
the wind at the east windows. 

As the first dim light appeared it was interesting to watch 
from the roof the flight of the approaching moths. They did 
not fly high in the air, on the level with the row of roofs, but 
approached the house fiying near the ground, at the height of 
the shrubbery, and when they came near to the house that 
harbored the females, they would soar upward and bob up over 
the edge of the roof. This showed that if they were following 
the female odor, it did not disseminate in volatile fashion to 
heights above, but was heavier than air and dropped to lower 
levels, at least in this moist atmosphere. In later experiments, 
this low flight was rarely seen; the moths approached from a 
distance flying at about the height of the roof. Probably in 
this case the heavy atmosphere would not permit the female 
odor to disseminate freely, but had a tendency to force it near 
the earth. 

Of the 42 newly captured males, only 3 had frayed wings, 
showing age; 39 had perfect wings with smooth pubescence and 
powdery scales in place, thus proving their youth. In fact, a 
number of them, when handled, ejected the chalky white fluid, 
a trait which is exhibited by these moths only soon after emerg- 
ing. Their wings seem to be thoroughly waterproof, for although 
they came in through the pouring rain, none of them were wet 
or soggy. 

One of these young males, as soon as it flew to the cage, was 
quickly thrust inside, to ascertain how much time would be lost, 
or rather spent, in courtship, before mating began. Within two 
minutes after he had entered the cage, mating had occurred and 
the pair was resting quietly. 

Exp. 13. May 18. Wind, southeast; station, 1 mile north- 
west. The point of liberation was carefully chosen, as nearly as 
I could determine, in the direct path of the wind, but between 
the hour of liberation, 9 p. m., and the hour of their flight, at 

wn, the wind changed and came directly from the south. 
Twenty-four native moths, captured at dawn that morning, were 
used in this test. These moths had been experimented upon in 
the glass box during the day (see p. 152) when the others had 


The Nuptial Flight 95 


been normally at rest, and the factor of fatigue should be con- 
sidered in the results of this experiment. 

The 24 marked moths had the following histories: 3 were old 
and had dilapidated wings, 1 was the young, wild male that had 
mated early that morning, and the remaining 20 were fresh 
young wild ones. Since the startling events of the night before 
had taught me that their regular time of flight is just before 
dawn, I began my watch at 3 a. m.; at 3:30 the moths began to 
arrive in great numbers, and at 4:30, before daylight was yet 
clear, their flight was at an end. The exact timing, the precision 
of their flight, seemed almost uncanny. We may well say ‘‘ ‘Tis 
the witching hour,’ until we can say something better, which, 
alas! we cannot yet do. 


Tn that hour, 54 males were captured, but only one in the lot 
bore the marks which told that it was one of the 24 which had 
been taken out the evening before to a point one mile distant. 
But the story is not complete until we add that three others 
came in at dawn of the second day. This is easily explained, 
hypothetically, by mere chance; it is quite natural that as the 

moths wandered in various directions, a few of them would, 
Sooner or later, come by chance into the path of the wind from 
the house, and from there follow the trail home. All four of 
those which came in were of the lot of 20 young wild moths. 
Moreover, we must constantly bear in mind that, although in a 
wild state, the males regularly emerge somewhat prior to the 
females, by this time there were probably a few wild females in 
the woods to distract our experimental males from their course, 
for these moths have no ‘choming”’ interest which would draw 
them back to the house where they had hatched, as a bee or a 
wasp would have, but their only interest is the call of their mates 
in that house, 

Exp. 14. May 19. Wind, south; station, 4 mile north. The 

fresh young males which had come in at dawn were marked 
and liberated at 10 p.m. One must not lose sight of the fact 
that these had already made one flight, from an unknown dis- 
tance, to the roof, and if they returned again it would be their 
Second successful journey, which would be an advent of no small 
Proportions in the life of a creature which lives only a few days. 

in the last test, the point of liberation was chosen in the 


96 Trans. Acad. Sci. of St. Louts 


direct path of the wind, but again the wind played tricks on us; 
at 12:30 it changed sharply and blew from the east, and by 3:30 
it was from the north to, the south, or just the opposite from 
what we wished. There was also a thunderstorm. The period 
of their arrival that night was from 3:33 to 4:40 a. m., during 
which time 39 males came to the cages. Five of these had been 
liberated six hours previously ; one had been taken out two days 
before, and the other 33 were all young wild moths. It seemed 
to me that these six experienced fliers found the cages more 
quickly, alighted more quietly and did not spend so much time 
in wild fluttering as did the first time fliers. That would be 
quite natural, since they were older and more experienced. The 
dawn of the following day brought in 9 more marked moths of 
this lot, and even two days after that (May 22 and 23), one 
each. Thus, out of 53 males liberated, 16 eventually returned, 
even amid variously shifting winds. However, the majority of 
them were out for so long a time that their return need not be 
regarded as any more significant than the arrival of any other 
aimless wanderers in the woods and shrubbery. 

Exp. 15. May 20. Wind, imperceptible; no leaf was stir- 
ring; station, 4% mile east. The 39 males, including the 6 which 
had already made two flights to the roof, were now duly marked 
and taken out into the park at 10:30 p.m. During the regular 
period of flight the following dawn,* 93 males came in; of these 
89 were newcomers, one had come to the roof the day before, 
and 3 were members of the lot of 6 that had made two previous 
flights to the roof! That proportion is too large to be passed 
by unnoticed, or to be attributed to mere chance (especially with 
the wind unfavorable) when contrasted with the much larger 
number of other moths which had exactly the same chances but 
less experience. Shall we suspect that these individuals were 
naturally endowed with a higher degree of sensitiveness oF 
ability than their fellows, or that their superior success was the 
result of profiting by experience? Is it possible that these, too, 
would have failed without something akin to place memory ? 
It is possible also that those of subnormal ability were eliminated 
in the first flight, and those taken on the second flight possessed 
superior sensitiveness to stimuli. One out of the remaining 33 


~~ In this case, at dawn the wind was blowing from the south. 


The Nuptial Flight 97 


was not the entire result of the test of the younger ones, how- 
ever; on the following morning 10 more arrived. This only 
shows that those which had had only one previous experience 
in coming to the roof were unable to repeat the performance in 
unfavorable winds, but probably had to wait until the winds 
shifted to a favorable direction or until, in their wanderings, 
they came into the path of the breezes. 

Exp. 16. May 21. Wind, northeast; station, 4% mile south. 
The 36 males used in this test were all young wild ones which 
had come in at the dawn of that day. At dawn, or to be exact, 
between 3:30 and 4:05 a. m., on May 22, 4 of these came in, and 
on the two following mornings two and three came in, or a total 
of 9 out of 36 in the three days. 

Exp. 17. May 21. Wind, northeast; station, 1 mile south. 
The setting for this test was the same as for the last, excepting 
that the distance was greater; here, too, the moths were not 
liberated in the direct path of the wind, but to one side of it. 
Of the 36 set free at 7:30 p. m., 2 came back the following dawn 
and one on the third morning. 

Exp. 18. May 21. Wind, northeast; station, 1% mile south. 
The time, place and wind were again the same as for Exp. 16, 
but the material was all bred males, six of which were two days 
old, one was one day old, and the other was a bred male which 
had successfully returned in Exp. 11, and was now seven days 
old. The last one came back the next morning, but the others 
were all permanently lost. 

Exp. 19. May 21. Wind, northeast; station, 14 mile south. 
Eleven experienced moths were liberated in the evening under 
Precisely the same conditions as in the three preceding tests. 
These, which had already made two flights to the roof, were 
Biven special colored markings, to distinguish them from the 
fommon stock. A few hours later, at dawn, five of these se 
Peared at the laboratory. Really, now, it is difficult to restrain 
oneself from jumping to conclusions, or at least from entertain- 
mg conjectures, when we briefly summarize the data from these 

t four experiments. All were exactly parallel as to pine, 
Place and weather. The wind was only partially favorable; = 
Was blowing toward the south-west, whereas to be favorable it 

uld have been directly toward the south, but this condition 


98 Trans. Acad. Sci. of St. Louis 


obtained for all alike. I hold that we are logical in assuming 
in all these tests that those which came in one and two days 
late did so only by virtue of their wanderings or of shifting of 
the winds, and hence do not have much weight in the present 
investigations. Out of 72 new males which had flown to the 
root from their wild haunts, 6 came back in this test flight (6 
more came in on following days); out of 7 young bred males 
which had never been out of doors before, none returned; one 
bred male which had made a successful previous flight did come 
back, and out of the lot of 11 which had made two previous 
flights, 5 came in promptly. All that we dare say at this point 
is this: while we have tried as far as possible to eliminate com- 
plicating factors, our problem is still a tangle. In this tangle 
we can from time to time recognize threads of different kinds, 
but the wisest method for us is to follow up and straighten out 
the one thread with which we have begun; in that way the 
others will be more easily disentangled later. The element of 
chance is always present to complicate matters, but here we 
are about to become involved with the factors of profiting by 
experience, and possibly trial and error; later we shall meet 
the more obvious but less knotty obstructions of old age and 
fatigue. The only kink conclusively disposed of here is that 
about 20 per cent of these moths can follow the trail of the 
female for a half-mile when the wind is semi-favorable. 

Exp. 20. May 22. There was a dearth of female cecropias; 
it seems, as Fabre complains, ‘‘when the farmer needs dung, the 
asses become constipated’’; now when I so needed a few females, 
only males emerged. I even went so far as to put cocoons in the 
incubator, but when they came forth, they were males and more 
males. Let us take inventory of our stock of females and esti- 
mate their drawing power. In one cage at the window were 
seven dead females and one feeble one nine days old; this cage 
had not been attractive to the opposite sex for the past two 
nights. In another window were four, aged 10, 8, 8 and 3 days; 
other experiments have shown that 2 and 3 days is the most at- 
tractive age; therefore for the approaching dawn the burden 
of attraction lay with this young moth. I waited with curiosity, 
and at 3:25 the first suitor arrived; they came on constantly ae 
groups or singly until 4:30, the usual time for the procession t 


The Nuptial Flight 99 


end. To my astonishment, the greatest number that ever flew to 
the roof were captured; four large cagefuls, or 119 moths, and 
about 20 evaded capture in the rush, making a total of 189! 
Of these, 93 were new native males, and 26 wore color markings 
which showed that this was their second or third flight to the 
roof. (The returns of these are recorded under their respective 
experiments.) This gives us the surprising evidence that a few 
females exert as potent a power of attraction as many. 


As I stood on the roof peering into the darkness to see whence 
they came, I soon found that they were not coming from the 
north or west, where the vista was open, but the majority of 
them bobbed up over the mansard of my house and the house 
on the south, but they did not come in through my east window; 
this indicated that they were coming from the southeast. In my 
restricted position I could not determine with certainty the 
direction of the wind, until I noticed that the light smoke from 
a tall chimney a block distant floated away toward the south- 
east in an unbroken ribbon. Here at last was convincing evi- 
dence to justify my long surmise that they are guided to their 
goal by the wind, and hence follow back against the current of 
air which brings them the message. 

Exp. 21. May 22. Wind, northeast; station, 2 miles south- 
west. Fifty males were taken out on this test flight; 44 were 
Wild ones which had come in that morning, and 6 inexperienced 
bred moths (3 were 1 day old, 1 was 2 days and 2 were 3 days). 
I tried to place them, as nearly as I could estimate, in the path 
of the wind, at the distance of two miles. None returned the 
next dawn, but on the following mornings one each came in. 
Two miles was a long distance to exact of them, but since others 
in later tests accomplished more than that, I cannot explain 
this almost total failure, unless it be that the chances were 
thereby greater for them to miss the direct current in the wind, 
°r, More probably, for them to meet native females en route. 

Exp. 22. May 23. Twenty-seven native males which had 
come in the day before were marked and liberated at 2 :30 a. m. 
im the darkened room, to see if at close range they would settle 
on the cages of the females. The only females in my possession 
at that time were the aged and worn ones mentioned above, but 
later tests proved that they were still capable of exerting their 


100 Trans. Acad, Sci. of St. Louis 


attraction. The females were in the west windows, and the wind 
from the northeast was blowing in at the east windows, so the 
wind passed over the males first and touched the females later. 
After an hour the males were found fluttering, and when the 
lights were turned on, they fluttered violently about the lamps, 
but they did not approach the cages; they wandered out of the 
windows instead. Of course the males’ agitation cannot be at- 
tributed to the presence of the females, because at this hour, 
3:30 a, m., they always become active. After watching them for 
some time I was convinced that they registered no reaction to 
the females near by in this position, and when they wandered 
away I did likewise. On the morning of the following day I 
found 10 of these marked moths clinging to the eages of these 
females. I have no record of the wind throughout the night, and 
do not know whether their eventual success was due to shifting 
breezes, their aimless wanderings, or some other cause. 


Exp. 23. May 23. In Exp. 20, I describe the dearth of 
females, and the marvel that so many males should react to a 
few aged specimens and a single young one. Even these were 
now a day nearer the grave, and not a new one had appeared 
to replenish the stock. The cages were watched from 8 to 4:30 
a. m., but not a native male came to them. During the entire 
period, only 3 came in, and these were marked ones, which have 
been recorded in a previous experiment. Was this due to the 
fact that these females had become so impoverished as to be 
impotent to exercise their attraction, or can it be that the un- 
usual influx of native males at the previous dawn had included 
about all the stray males in the region? I can hardly imagine 
the latter to be true, since I saw the moths coming in from only 
one quarter of the compass. The three which did come 1 
had made successful flights previously, but again one cannot 
tell whether, because of their experience or superior sensitive- 
ness, they could react to weaker female emanations, or whether 
they were aided in their return by something akin to place 
memory. 

Exp. 24. May 23. Wind, east; station, 30 feet west. The 
test on the preceding evening indicated that the males cannot 
find the females, even in close proximity, if the wind is blow- 
ing in the wrong direction. Now we liberated at 8 p. ™. 23 


The Nuptial Flight 101 


native males (19 new ones, 2 which had made two successful test 
flights and 1 which had made one test flight), 30 feet west of 
the windows where the females’ cages were, and on the ground 
about 25 feet below them, with the wind blowing from the 
females toward them. Males of this species have the ability to 
fly long distances when the wind is favorable ; can they make a 
successful flight for a short distance, or is proximate orientation 
more difficult than distant orientation? In the bright moonlight 
between 11 and 11:10, three males came in; at 12:05 a fourth 
one; and between 3:05 and 4, six more, all of which had been 
taken out for their first test, and the one which had made one 
successful previous test. Here we see that 11 out of 23 males 
can find the females at a short distance when the wind is right, 
even if the females are aged and decrepit and only three in 
number. Some of these males came in before the usual hour 
of dawn; these were undoubtedly influenced by the bright moon- 
light, but if four were so influenced, why were not all? In an 
experiment with females on the ground and also on the roof, 
I had found approximately an equal number of males coming 
to both places, showing that odor trail can be followed by the 
males regardless of such an elevation. 

Exp. 25. May 24. During the day, two females emerged, 
and these with the three old ones were placed in the windows. 
Two males appeared at 3:05 and 3 :10, a little earlier than usual, 
and between 3:25 and 4:30 71 came in and were captured, and 
about ten evaded capture, making a total of 83 which re- 
sponded to the attraction of these females. A census of these 
73 revealed 48 wild ones, of which 25 were young and 23 old 
and worn, and 25 bearing our marks, proving previous flights. 
This is a larger proportion of old ones than had been seen on 
other mornings, and the fact that old ones came in also shows 
that they must have been in existence and probably would have 
responded when they were young if the female attraction had 
been sufficiently strong. This circumstance also shows beau- 
tifully why so few old males came to the roof. The reason is 
that they all respond while they are young. It also shows that 
when the female attraction is too weak to lure them, they can 
still respond when they are old when they meet it later in life. 

ing the influx the moths could be seen coming from the west 
and southwest ; the wind was from the northeast. 


102 Trans. Acad. Scr. of St. Louis 


Exp. 26. May 24. Wind, east; station, 15 feet west. At 
11:50 p. m. five males were liberated at the edge of the roof 15 
feet from the females, and with the wind blowing directly upon 
them from the cages. Three of the five flew to the cages at 
3:25, 3:40 and 3:55 a. m. This shows clearly that they ean orient 
themselves, even if the distance is short. But more interesting 
is the evidence that, despite the fact that the cages were only 
15 feet away, the moths did not fly to them until dawn, the 
precise moment of their customary flight, almost four hours 
later. This demonstrates, of course, the dominance of a stand- 
ard rhythmic periodicity, but since the moths sometimes react 
to moonlight, one suspects that this periodicity is not regulated 
by the elock, but by a condition of light which acts as a stimnu- 
lant. There was no moon that night. Later experiments show 
that when the moon is bright they sometimes fly to the females 
without waiting for the streaks of dawn to act as a stimulus. 


Exp. 27. May 25. One more female cecropia had emerged, 
while some of the dead ones (functionally speaking), had died, 
so this dawn found three young females and one old one dis- 
played in my windows. These attracted 42 moths from 3:30 to 
4:30 a. m.; this was about half of the number that had come in 
on the preceding day when fewer young females were present. 
This shortage may be explained by either the deficiency of the 
wind, or the probability that yesterday’s response had drained 
the population. Sometimes no wind was perceptible, and again 
there was a faint breeze shifting from one direction to another. 
It may be that returns are better when the wind is stronger, 
for that would clear away the city’s smoke and carry the emana- 
tions more directly. Of the males captured, 41 were native new- 
comers (26 old and 15 young); one bore a mark showing that 
he had come (at this late date) from a two-mile point, as re- 
corded in Exp. 21 on May 22. 


Exp. 28. May 26. I fell asleep that night, and instead of 
going on watch at 3 o’clock as I had planned, it was 4:20 when 
I hastened to the third floor. The rain, which had been falling 
heavily all night, continued. I found a dozen males fluttering 
about the room, and in all probability many had come and gone 
in my tardiness of fifty minutes. However, on account of the 
rain the light conditions were less intense at 4:50 than they 


The Nuptial Flight 103 


usually were at 4:30 on clear mornings, and instead of the flight 
stopping at the usual time, it continued for twenty minutes 
longer, or until 4:50; this point is interesting in that it demon- 
strates how much a slave to certain intensities of light these 
creatures are. In all, about 20 males were taken, a small num- 
ber, but sufficient to demonstrate conclusively that heavy rains 
do not deter their flight, and that after flying in the rain they 
are none the worse for wear. Since it had rained steadily from 
7 p. m. to 7 a. m. (1.6 inches of rain fell), this flight shows that 
the rain does not obliterate their medium of communication 
(odor?). All of the males were native ones that had never, been 
on the roof before. If one could prove that the action of this 
amount of rain could destroy the female odor or cause it to 
settle on or near the ground where it could not disseminate, and 
then if the males still flew to the cages, one would have to at- 
tribute the action to something other than odor. 


Exp. 29. May 26. Wind, east; station, 30 feet west, on 
ground. This experiment and the three that follow (also Poly- 
phemus Exp.) were conducted during the night of May 26-27, 
and are of especial interest because the moon shone for certain 
Periods during the night and the irregular and unusual flight 
of the moths correlated beautifully with the periods of moon- 
light. The intricacies of their reaction to intermittent and con- 
stant moonlight will be considered in detail later in these pages. 

ourteen male cecropias were liberated in the back yard on the 
ground, 30 feet west of the females, at 11:55 p. m., with the 
wind blowing directly toward them. Six of these came back, 
one at 12:05 (after only ten minutes), one at 1:25, three be- 
between 3:18 and 3:40, and the sixth one came in at dawn a day 
later. 


Exp. 30. May 26. Wind, east; station, 44 mile west. Thirty 
new native males and one which had made two previous flights 
were liberated a little further west and three minutes later than 
the last lot. Thirteen of these returned, the first three arrived 
22, 72 and 77 minutes after they were set free, nine came in 
between 3:40 and 4 a. m., and the experienced flier came in 
the next day at dawn. 

Exp. 31. May 26. Wind, east; station, 1 mile west. Thirteen 
males from 1 to 3 days old, which had emerged from cocoons in 


104 Trans. Acad. Sct. of St. Louis 


the laboratory, were liberated one mile west at 11:48 p m. Seven 
of these successfully made the one-mile flight, 4 of them coming 
in on the first night and 3 on the second. The first ones ar- 
rived in 8, 25, 32 and 82 minutes; those on the following night 
arrived at 1:10, 4 and 4:10 a. m. It is interesting to note that 
it was possible for one moth to make the flight of a mile in 8 
minutes; in fact, he got home before I did, and my son had him 
eaught and properly recorded when I arrived. And this moth 
had never been out of doors before and was only one day old 
when liberated! 

Exp. 32. May 26. Wind, east; station, 1 mile west. This 
test was precisely the same as the last, excepting that wild males 
which had flown -to the laboratory only that morning at dawn 
were used. They were 15 in number, and were liberated at 
11:45 p.m. Five returned at the following times: 12:03, 1:12, 
1:22, 1:55 and 2 a. m. Thus the sprightliest of these made 
almost as good time as a human competitor. 

In the preceding four experiments it is evident that some of 
the male cecropias came in at hours that differ greatly from their 
regular hour of dawn. These were undoubtedly influenced by 
the light of the moon, but an analysis of the data in a later 
chapter shows that the bred males are more subject to this influ- 
ence than the native ones. 

Exp. 33. May 27. During the dawn, in addition to the 
marked cecropias which returned, 58 wild ones came in, of which 
47 appeared young and 11 old. 

Exp. 34. May 27. Wind, east; station, 134 miles west. 
Twelve unmated bred males, from 26 to 30 hours old, were 
liberated in or near the path of the wind, at 10:50 p.m. Two 
came in that night at 12:01 and 12:18 a. m., one each at dawn 
of the third day and fourth day thereafter. The first two made 
the distance of 134 miles in the brief time of 114 and 1% hours. 

Exp. 35. May 27. Wind, east; station, 134 miles west. All 
conditions were the same as the last, excepting that experienced 
fliers were used; these 11 cecropias had all made one test flight 
before. Three of these returned that night, the first at 12:50, 
having made the trip in two hours, and the other two at dawn. 
Here the experienced fliers did no better than the novices. 

Exp. 36. May 27. Wind, east; station, 14 mile east. Four 


The Nuptial Flight 105 


bred cecropias, from 1 to 4 days old, were liberated at 11 Pp. m., 
where the wind blew from them toward the females. To my 
suprise, one, four days old, came back at 12:37. 

Exp. 37. May 27. Wind, east; station, 1 mile east. In this 
test 19 wild males which had flown to the roof that morning, 
and 2 which had returned in a previous test, were liberated in 
an unfavorable wind at 11:05 p. m. Two returned the follow- 
ing dawn, one on the second and one on the third morning later. 
The first three were young, and the last one to return was old. 

Since this was a test to see if the males can fly to the females 
when the wind is not favorable to carry odors to them, we really 
should consider only those which came in the first night before 
the winds shifted. I do not want to juggle my evidence, but 
may it not be that mere chance might lead 2 out of 21, through 
aimless wanderings, into the path or region of the attraction? 

Exp. 38. May 27. Wind, east; station, 114 miles east. Ten 
young and 4 old wild males which had come in that morning, 
and 4 which had made two other flights, were taken out at 
11:10 p. m. for this long flight in an unfavorable wind. Just 
one returned, making the mile and a half in two hours. 

Exp. 39. During the dawn of May 28, 19 native cecropias 
flew in, of which 10 were old and 9 young. Were these morning 
Visitors fewer because the wild population was becoming de- 
Pleted, or because females other than ours existed and were 
diverting the attention of the wild males or perhaps our experi- 
mental moths as well? 

Exp. 40. May 28. Wind, southeast; station, 3 miles north- 
west. This daring experiment was tried with a large number 
of males of various histories, to see if it is possible for the — 
to return for a distance of three miles when the wind is in their 
favor, that is, blowing from the females toward them. There 
were 28 bred males one and two days old, 12 bred males which 
had made successful previous flights, 17 wild ones which had 
come in at dawn that morning, and 22 from the morning before, 
making a total of 79 moths. Only one returned, and that 
on the morning of June 1, so it seems to have come in by chance, 
although it is interesting to learn that they wander as far as 
three miles in their quest. I feel confident that these creatures 
are capable of returning that distance directly, instead of by 


106 Trans. Acad. Scr. of St. Louis 


chance, if the direction of the winds could be exactly ascertained 
and urban hindrances eliminated. 

Exp. 41. May 28. Before midnight a heavy fog settled over 
the landscape and the wind ceased; there was not enough breeze 
to flutter a leaf or waver a film of light smoke in the air. No 
moths appeared until the hour of dawn, when 28 came in (27 
young native males and one marked bred moth) in spite of the 
presence of the fog and the lack of wind. 


Exp. 42. May 29. For the first half of the night the moon 
shone brightly ; after midnight it was partly obscured by clouds; 
a fitful wind blew from the east. Although several fine young 
females were on the roof, no cecropias came in until 3:40 a. m., 
when 8 young strangers and one marked one which had been lib- 
erated one mile east three days before, came in. Since they 
were so few, there was ample time for me to watch their arrival; 
most of them came from the west or the southwest. Some of 
them missed their mark and flew too far, over the housetop, but 
returned after a few moments. The dearth of males was con- 
spicuous, but on second thought it was not surprising. During 
the first few experiments there was a dearth of females from 
my cocoons in the laboratory, but at this time the majority of 
those emerging were females, and the shortage was among the 
males. If this condition was duplicated in the wild population, 
it is easy to see how the few wild males would be abundantly 
occupied in their native haunts. May it be, also, that the gentle 
summer breezes did not carry the emanations of the females as 
far as did the strong, direct winds of a few days before, and 
hence reached only those near by? 

Exp. 43. May 30. Wind, faint breeze from east; station 44 
mile east. The following 30 cecropias were liberated in Tower 
Grove Park at 9 p. m.: 7 natives that had come in at dawn 
of that day, 12 from the dawn before, 5 from two mornings 
before, four bred males aged one and two days, and 2 natives 
which had come in from a previous test flight. None of the bred 
cecropias returned, but at 11 p. m. one wild one which had come 
in the day before arrived, and at dawn three more wild ones 
returned, and the following dawn three more. This shows et 
least that four out of 30 (considering only those which came 0 
the first night) could find the females against the odds of a dis- 


The Nuptial Flight 107 


advantageous wind for a distance of 14 mile, but, it must be 
remembered, those which returned had made a previous flight 
to the roof. 

Exp. 44. May 30. The above paragraph tells the activities 
of moths under experimentation on May 30. Here we record 
the action of wild ones in their relation to the moonlight on the 
Same night. The moon shone from 9 p.m. With an abundance 
of females of both cecropia and polyphemus on hand, males of 
both species were coming to the roof that night. In addition to 
the one marked cecropia recorded above which came in at 11 
o’cloek that night, 4 more wild ones came in at 11:35, 12:02, 
1:50 and 3:10, and during the usual hour 10 more arrived. Thus 
in spite of the fact that the moths are attuned to fly at the hour 
of dawn, one third of these came in during the moonlight, con- 
trary to the custom of the great majority. Was this because the 
moonlight was of just the right degree of intensity to simulate 
the dawn and elicit their response, or were these four individuals 
peculiarly endowed with some faculties for seeking their mates 
m any light, which their brothers did not share? 

Exp. 45. June 1. I overslept, so made no records of the 
small hours of the night, but at 4 o’clock, when I arrived, 6 wild 
males were flying about the cages, and 9 more came in before 
4:30, making a total catch of 15 this night. 

Exp. 46. June 1. Wind, southeast; station, 2 miles north. 
Thirty-eight bred males, from 3 to 5 days old, were liberated in 
Forest Park, a little to one side of the path of the wind, at 4:45 
P.m. These moths had never before been out of doors. Only 
one of this large number returned, and that at 10:30 the same 
evening, after an absence of six hours, for the trip of two miles, 
at an hour when most moths are at rest. 

Exp. 47. June 1. Wind, southeast; station, 3 miles north- 
west. The point of liberation was chosen, as nearly as we could 
estimate, in the path of the wind. The 61 cecropias were: 12 
native moths which had come in at dawn, 10 from the day be- 
fore, 7 native moths which had made an additional test flight, 
31 which had emerged in the laboratory the day before, and 1 
bred male 4 days old. Of these 61 cecropias, 15, or about 25 per 
cent, returned from their enforced flight of three miles! 

These returns are interesting in point of time and proportion 


108 Trans. Acad. Scr. of St. Louts 


of moths of various histories. Of the 12 wild ones caught that 
morning, 4 returned (33 per cent) ; one came in the following 
dawn, 6 hours after liberation, one the morning of June 3, and 
two at dawn of June 4. However, only one came in at once, 
and the others wandered for two or three nights. Of the 10 
caught the day before, 3 came in (also 30 per cent), but none the 
first night, two the second and one the third dawn. Of the 7 
moths which had already flown to the roof twice (once volun- 
tarily and once under test), just one returned, an hour and 
forty minutes after being set free at 10 p.m. Of the 31 bred 
males, one day old, 6 (near 20 per cent) came back, and, the 
more surprising, all the first night; the first ones came in at 
10:50, 11:40, and 11:45, and the other three at dawn. This 
appears to be the most remarkable record yet established; for 
it is truly wonderful that so many moths should come back 
promptly from a distance of three miles, when mates must have 
been abundant in the very park where they were liberated. And 
last, but not forgotten, is our one bred moth, four days old, 
which distinguished itself by coming back in two hours and 
three minutes, in spite of its youth and inexperience; it, too, 
made the three miles without waiting for the customary hour 
of dawn. This makes 4 of the 15 which came in before their 
customary hour of flight. It is highly interesting to note that 
all which came in during the early hours of the night returned 
during the first night; those which came on following nights all 
came at dawn. There must be a reason; were the meteorological 
conditions during the early hours of the night of June 1-2 more 
favorable than those of the two nights following, or were these 
particular creatures which came in early endowed with finer 
sensitiveness or superior ability which enabled them to surpass 
their fellows, and would likewise have brought them in under 
different or even adverse conditions? And the splendid returns 
for the entire lot, 15 out of 61, elicit the same questions; just 
why should so many succeed in this severe test, when so many 
failed even in simple flights? 

Exp. 48. June 1. During the night of June 1-2 the native 
males that flew in numbered 15; of these, 12 came at the usual 
hour, about dawn, and the other three came at 10:40, 11:50 and 
1:35 o’elock. In addition, 8 marked cecropias, which have been 


The Nuptial Flight 109 


recorded in other experiments, came in. There was hazy moon- 
light before midnight, and 7 moths came in during that time. 
All of these came from the northward; the wind was from the 
south. 

Exp. 49. June 3. The moon was hidden during the early 
hours of the night of June 2-3, but at 3 a. m., when I took my 
position on the roof, a half moon was shining. The first male 
arrived at 3:27 and the last at 4:25. There was a very slight 
breeze from the south, sometimes shifting to the southeast; all 
of the moths came from a northerly direction. There were 7 
young native moths and 5 marked ones already accounted for 
elsewhere. 

Exp. 50. June 4. The early hours of the night had been 
very dark; when I took my post on the roof at 3 a. m., a half 
moon was shining and the wind was blowing from the southeast. 
The first male flew in at 3:35, and the last one at 4:30. Only 6 
native and two marked moths flew to the cages during this 
Period. 

Exp. 51. June 4. Wind, south; station, 1% mile north. The 
65 males used in this experiment had accumulated from the 
following sources: 9 wild moths had come to the roof two days 
before; 18 wild moths had come to the roof one day before; 7 
wild males had come in at dawn that morning; 14 bred males 
had emerged from their cocoons three days before; 8 bred males 
had emerged that day; 9 bred males, two and three days old, had 
already mated. These were liberated 14 mile away, as nearly as 
Possible in the path of the wind, at 9:45 p. m. 

Of the first lot, only 1 of the 9 returned, and he came in at 
dawn, after an absence of six hours. Of the next lot of wild 
ones, 5 out of 18 came in, two of them in 35 and 65 minutes and 
the other three at dawn. The younger wild males distinguished 
themselves by making the best record; 4 of the 7 came back, one 
at 1:07 a. m., and the others at dawn. Whether this superior 
ability is to be explained by the probable youth of the con- 
testants, or by the fact that they had more recently made the 
flight to the roof (when they had come in of their own volition), 
and thus, in some way, profited by the experience, we shall not 
here presume to decide, but only take cognizance of the fact that 
this is the second time this condition has oceurred, where, in 


110 Trans. Acad. Sci. of St. Louis 


exactly parallel tests, the wild males which had flown to the 
roof at dawn of the same day were conspicuously more success- 
ful than their brothers who had come in similarly one or two 
days before. Out of 14 bred males, three days old, 4 returned; 
none of these waited for dawn, but all arrived between 12:15 
and 1:20 a.m. Of the 8 moths which had emerged the same 
day, two returned the same night at 11:40 and 1:20 o’clock, and 
two more came in two nights later. In the last lot of mated 
males, 2 out of 9 returned the same night at 11:20 and 12:50. 
This shows, again, that even after having mated, the moths 
respond to the attraction of the females for a distance of at 
least half a mile. Thus, out of the total of 65 that were liberated, 
20, or 31 per cent, returned ; 18 of these came the first night and 
2 later. 

Exp. 52. June 4. In addition to the marked moths that 
came in as recorded in the last experiment, during the night of 
June 4-5, 9 new wild males flew in. They did not wait, this time, 
for the usual hour of flight, but they were well distributed 
throughout the night, from 10:30 until dawn. The cecropia 
season was drawing to a close. From our cocoons in the labora- 
tory, only 22 emerged from June 5 to 8, and none at all after 
that. 

Exp. 53. June 6. During the hour of dawn, 7 wild moths 
and 1 marked one (already accounted for) came in from the 
north. The breeze was from the south. 

Exp. 54. June 7. Being badly in need of sleep, I did not 
get up during the night to receive the eager lovers, but at 7 
a.m. I found 6 wild cecropias (4 old and 2 young) at the cages. 

Exp. 55. June 9. Wind, northeast; station, 14 mile south. 
Several cages full of cecropia females, two and three days old, 
were exposed to the gentle breeze on the roof. Three males, 
each with one-half of each antenna removed, were liberated at 
9:14 p. m., 14 mile south, a little to one side of the path of the 
wind. At the following dawn, one of these came back. 

Exp. 56. June 10. During the customary hour of flight, 25 
wild cecropias came in. All of these males were young. This 
large number, at the end of the season, would indicate that 
native females are scarce or too old to be attractive. : 

Exp. 57. June 11. The rain of the previous day continued, — 


The Nuptial Flight 111 


with a strong wind from the east. Up to 3:40, no moths came 
in, and I fell asleep. At 7 o’clock I found that the lid had 
blown off one cage, and every one of the five females therein had 
united with a wild cecropia. This 100 per cent record of mating 
is more interesting when compared with the results of later 
experiments, wherein only 9 out of 28 couples mated when 
thrown in close proximity in small cages, but where all motion 
of the air was excluded. Six other wild males were found in 
the room. 

Exp. 58. June 12. Wind, west; station, 1/5 mile east. The 
22 native males were liberated at 11:15 p- m., in the park. 
These had come in during the last two dawns. The eyes of 
four of these were thickly painted with stove enamel; this was 
done to learn if the eyes do function in the moths’ quest for 
Mates. None of the normal males returned in this experiment, 
but, mirabile dictu! all four of the blinded ones came back that 
same night! 

Exp. 59. June 12. Wind, west; station, 1/5 mile east. This 
lot included 10 cecropias which had come to the roof at dawn 
that morning, and the one which had come back successfully 
with only one half of its antennae. The antennae of all of the 
others were entirely removed. It was at first very flattering to 
find that we got a 100 per cent failure to return when the 
antennae were entirely amputated, in contrast to a 100 per cent 
ability to return with eyes covered, but of course our evidence 
from the antennaeless moths is weakened by the fact that the 
able-bodied moths the same night failed, for some reason = 
we cannot fathom. However, these two experiments give us 
Some inkling of the relative importance of antennae and eyes. 


Exp. 60. June 12. I watched all the night of June 12-13, but 
nO cecropias came in during the early hours. Before midnight, 
the wind blew from the west, but at 3:20 it shifted to the north- 
West and became stronger. The first one came in at 3:29, and 
until 4:20, 26 young wild males arrived, and the four blinded 
Ones mentioned above. This flock came in from the south and 
Southeast. It is surprising to me that so many should come in 
at this date, inasmuch as the last of my cocoons in the labor- 
atory had hatched four days prior to this. May it be that the 
shifting of the wind carried the emanations from the laboratory 


112 Trans. Acad. Sci. of St. Louis 


over certain fields which for a few days had not been in the 
path of our breezes? 

Exp. 61. June 13. While I was on the roof all night wait- 
ing for cynthias which did not return, I had leisure to watch 
for the arrival of cecropias also. This was a bright starlit night; 
the breeze was not perceptible, but the smoke issuing from a 
tall chimney rose high in the air and disseminated toward the 
southeast. My vigil was in vain, for none came early. During 
the dawn hour, 19 came in, 16 of which were from the south- 
east; the direction of the others was not noticed. 

Exp. 62. June 15. Wind, imperceptible; station, 100 feet 
west. Fifteen wild moths which had come in at dawn on June 
13, and 3 of the blind ones which had returned in Exp. 58, 
were used in this test: The eyes of all were covered with the 
black enamel. They were liberated 100 feet west, with no wind, 
at 11:30. At dawn, 3 of these came in; those which were out 
for their second sightless flight were not among them. 


Exp. 63. June 15. Wind, none; station, 100 feet west. 
Fifteen moths with mutilated antennae figured in this test. 
Five of these had half of each antenna off; five were without 
the entire left antenna and five without the right; two 
normal moths were added as controls. During the fol- 
lowing dawn, 4 of the mutilated cecropias (two with half 
of each antenna, one with right and one with left antenna) re- 
turned, but only one of the normal moths came back, and he 
came only as a wanderer a day later. I wanted to repeat this 
test with a large number of moths, to see if, as appears here, 
those with half of each antenna are more capable of following 
a trail than those with all of only one antenna, but the quantity 
of material was too depleted to afford them in large numbers. 

Exp. 64. June 16. While I was kept busy all night catch- 
ing cynthia males which came to the roof, no cecropias came 
before 3:40, and they ceased at 4:25. During that 45 minutes, 
15 wild and 7 marked cecropias came in. It was suprising that 
among the 15 wild ones, all but 2 appeared young, perhaps 
a day old; this indicates that the Missouri wild moths were 
emerging later than my New York stock. 

Exp. 65. June 17. I waited all night and took the 
eynthias which came in. The work so far indicates that these 


The Nuptial Flight 113 


two sister species have quite different habits. The cecropias 
concentrate their activity about and just before the hour of 
dawn, and only occasionally some aberrant or strangely stimu- 
lated individuals fare forth during the earlier hours of the 
night. The cynthias, on the other hand, prefer the midnight 
hour for their flight, and seldom are caught abroad at dawn. 
And so this night the first cecropia came in at 3:40 and the last 
at 4:25, 12 native males and 1 blind moth from an earlier test. 

Only a few decrepit old female cecropias remained on the 
roof; it seemed unlikely that these could retain their powers of 
attraction. In fact, on this night and the preceding one, it 
was apparent that the incoming males showed an unusual 
amount of indecision in settling on the cages; they flew about 
aimlessly before they came near the cage, and even then they 
would sometimes fly away without stopping. Out of the 13 
male cecropias, only one eventually settled on a female 
cecropia’s cage, while 6 settled on cages of young cynthias, and 
the remainder were captured with the net when I thought they 
were about to escape. It is interesting to note here that, while 
the cynthias were of various ages from one to six days, one 
cecropia alighted on the cage containing the day-old cynthia 
and 5 cecropias chose the two-day old cynthias and ignored the 
others, 

Exp. 66. June 17. Wind, east;; station, % mile west. The 
Previous experiment gave evidence that the male cecropias are 
to some extent attracted by cynthia females. I now had in my 
Possession two old and decrepit cecropia females. These were 
taken to the rooms below and locked up in an almost air-tight 
closet. Then with plenty of young eynthias on the roof, at 
11:50 p. m. I liberated 30 male cecropias in the path of the 
Wind, as nearly as I could estimate, and % mile distant. The 
lot included 2 males which had returned minus half of each 
antenna, 2 which had returned with blackened eyes, 11 wild 
males had come in at dawn that morning, and 15 from dawn of 
the day before. None of these 30 returned, but 8 young wild 
Cecropias flew in on the roof. 

Exp. 67. June 18. Wind, south; station, 200 feet north. 
Wishing to test again the reaction of cecropia males to eynthia 
females, I took all the males I had, 14 in number, and liberated 
them in the direct breeze. Eleven of these had been fooled once 


114 Trans. Acad. Sci. of St. Louis 


by the cynthias, and the other three, twice. Perhaps they had 
been misled too often, for none came to the roof again; but the 
attraction was potent to the inexperienced young males, due 
either to their unsophistication or their youthful antennae, for 
at dawn 14 new wild male cecropias came in, when we had not 
a cecropia female on the place! But let us give them credit 
for the fine discrimination which they exhibited, for they were 
extremely active in their flight and not one actually alighted 
on the cages, but fluttered about for some minutes as if in con- 
fusion, and then wandered away. Only when they were escap- 
ing thus were they captured with the net. It should be empha- 
tically stated that this indicates a certain kinship between the 
two species. It denotes, in my opinion, that the parting of the 
ways of the two species has been comparatively recent; that 
the cecropias have not travelled far enough from cynthias, 
phylogenetically speaking, to have altogether lost the recogni- 
tion of the familiar odor. 

Exp. 68. June 20. I was up all night and captured about 
70 cynthias, but no cecropias came before 3:20; then only 5 
came in. These came, of course, in response to the cynthias’ 
lure, since all cecropia females had long since ceased to exist. 

Exp. 69. June 25. The last wild cecropia flew to the 
cynthia cage on the roof at 4 o’clock this morning. 


Summary. 

In reviewing the experimental work on cecropias, we find 
that when the females are placed in cages at the open windows 
or on the roof, the wild males and also those bred in confine- 
ment and liberated at various distances come to the cages dur- 
in the night. During the period of experimentation, May 7 to 
June 25, 961 males flew to the cages on the roof. Of this num- 
ber, 170 were marked moths which had been bred from New 
York cocoons and had been liberated at various points and di- 
rections in an attempt to learn what distance they can travel 
and what factors determine their guidance. During this 
period, 791 native wild males flew to these cages containing the 
New York females. Of course no females came in, and none 
were taken out on test flights. The age of these wild moths can 
be approximately estimated by the condition of the wings. of 
those which came in, 715 were obviously fresh, young ones, and 
76 appeared old and tattered. 


The Nuptial Flight 115 


I have said that these insects were attracted by the female 
cecropias; this statement needs to be amended somewhat, for 
in the last four experiments, 28 male cecropias came to the 
cages containing only the cynthia females, after the cecropia 
females were all dead; they were deceived by the similar or re- 
lated cynthia emanations. The behavior of the cecropia males 
showed, however, that the deception was not complete. 

A summary of the data shows (see Table No. 1), that out of 
735 marked males liberated in various directions and at distances 
varying from 25 feet to 3 miles, 170 returned to the females 
on the roof. This was 23.1 per cent of those liberated. If this 
result seems small to the reader, let me remind him that in the 
region where 791 wild males came to us voluntarily, there must 
have been an enormous number of females in the open to en- 
tice our experimental moths from their path; hence to me it 
seems really wonderful that any at all should return to a bleak, 
Second-story roof in an area of roofs and brick walls. The per- 
centage of returns of this species, a native of Missouri, com- 
pares well with the returns of the cynthias, which had the field 
completely to themselves, since in the wilds of this city there 
are no females of his species to waft her emanations on the 
breezes and thus swerve him from his course. Later pages will 
show that the per cent of returns of cynthia was 31. In the 
light of this comparison, I feel doubly assured that the returns 
of cecropia are good. 

A tabulation of the figures shows that the 170 which were 
liberated at various times during the evening came in during 
the dawn* of the first, second, third and fourth morning in the 
following proportion: 

1st morning, 106. 
2nd morning, 50. 
3rd morning, 11. 
4th morning, 3. ; 

The time of flight is -defined with surprising sharpness; it 
seems to be the established habit of this species to make the 
nuptial flight during one hour, just before and during the 
Period of dawn, from 3:30 to 4:30 o’elock, with deviations from 
this time seldom exceeding five or ten minutes, excepting in the 
©ases mentioned in the footnote. 
ed 

*In a few experiments the moonlight elicited an earlier response. 


Trans, Acad. Sci. of St. Louis 


TABLE No. 1 


SAMIA CECROPIA 


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persieqryT Toquin Ay oOo -— se sw OH : _ = 9 = Rew 2 
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36 a 1 Od EM Ae 11:50 p.m E Yes | 1/200] Ww 5 0 Cae ee err he 
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29 | 26 |......{ Moon | 11:55 p.m. E Yes | 1/200) W | 14 ibe ie Ee 5 bale eid anne 6 0 0 

80 | 26 |...... Moon | 11:58 p.m. E Yes ¥ WwW i} 3i1 0 | 31 Pal! 12 a ee ae 13 0 0 

31/26/ U | Moon /1148pm.| E | Yes} 1] w liz lis | o eos | ee, 7/13 | 7 

2 4 Ww oon | 11:45 p.m. E Yes 1 Was ST ere We ae be 5 0 0 

33 | 27 a eee el ve i W Tis Tis Boe dives oy ou ae ad apa era fe Ae He oap) a 
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war Ui... 00 p.m.} E No E ee 6 8 toa hl ee ee 1 1 
mee tL... 11:08 E No | 1 Or er a err. 1 pa wee AND OBO 

38 Pew to... 11:10p.m.| E No | 1% Peele Pee ek Be Pe a ae 

40 Pw 9:45 p.m. | 8. E. | Yes | 3 Peewee OL Se ah as Ed lea Tye 

42 | 20 |! TEE HOBBES 1018 URN SISO! 5 oP ar SASS a NEON i ees Cok ion Cae be Be NOE RD ON 
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66 OU INR xu ce) aed sy (CIN IRE ERAN GCE AND AAMIR MBOBEG Qhintay uitace 2 143.1 hsm Geen Aiee Gara 

COE ARO babii vse ci Leal YOUR Oy IMS FESS AERC SIC RAS aN iO Ife wy os ta RE By apa 

bd ; DSS 2 aes Cate GON oe eae Oe eavea as Came cy cairns diy oo Sah Aas bees 

Be Oe aerate 


{Dawn following. +—Cecropias are all dead. The males flew to Cynthias. ‘thdace experiment, 


by wudny ayT 


LIT 


118 Trans. Acad. Sct. of St. Louis 


In considering the return of the moths when liberated in 
favorable or unfavorable winds, only the 106 which came in 
during the following dawn may really be accepted as reliable 
evidence, since we cannot know what factors, the shifting of 
winds, the interference of other mates, etc., are responsible for 
their wanderings. Even when only a few hours elapse between 
the time of liberation and the hour of return, there is abundant 
chance for the wind to change for a time, or to be deflected by 
the obstructions of the city. Out of 630 moths set free in 
favorable or partly favorable winds, or no wind, 98, or 16 per 
cent, returned at the following dawn; out of 78 liberated in a 
wind which was at the time of liberation unfavorable, 8, or 10 
per cent, returned. This method of studying the direction of 
flight of the moths and their method of orienting themselves in 
relation to the wind is not so fruitful of results as merely to 
watch keenly in the moonlight or dawn, and see from what di- 
rection they fly. At times the moths came too thick and fast 
for me to see their direction, but in the many cases where I was 
able to make this observation, the great majority of them 
arrived flying against the breeze. In the experiments with 
cynthias, as you will see later, we found data much more con- 
elusive in favor of their coming home against the wind; here 
we find that with the wind favorable for carrying the female 
odor to the point of liberation of the males, 38 per cent re- 
turned, and in an unfavorable wind only 8 per cent returned. 
This type of experimentation and deduction is the correct one 
for cynthia, for these moths fly early in the night; this is so 
soon after the time of liberation that there is little chance for 
the change of wind. Moreover, their attention is not diverted by 
wild females in the shrubbery. 

Thus the majority of them came galloping in facing the 
wind, from which we conclude the wind had carried them the 
message of the whereabouts or at least the direction of their 
mates. Some proved their ability to come in repeatedly, and 
some of these distinguished themselves either for speed or for 
overcoming difficulties. Whether this superior ability was due 
to finer native sensitiveness, which resulted in superior ability 
in this most vital quest, or whether their native endowment was 
augmented, after one or two experiences (which covered tenth 
or more of their natural lifetime), by associative memory whieh 


The Nuptial Flight 119 


aided in their later returns, I shall not presume to say at this 
point. I should like to think that these creatures profit by 
experience, but in a purely speculative way it seems more 
logical to attribute this superior ability to the natural 
(sensory) endowment of certain individuals. In their natural 
wild life, generation after generation, these moths have no pos- 
sible use for the ability to remember the trysting-place with 
their beloved and return to it, but it is hard to conceive of 
anything more vital in the perpetuation of the species than a 
fine native sensitiveness whereby the male can once locate his 
distant and unseen mate. The more specialized this sensitive- 
hess, the greater chance the individual has of leaving like 
progeny, for certainly the male that is lacking or deficient in 
this native faculty is in no danger of perpetuating his stupidity. 

Basing my judgment upon the action of the great majority 
of these moths observed, I feel convinced that the medium of 
attraction between the sexes is odor, or something so closely 
akin to it that we need not seek another name for it; that the 
males follow this odor trail on the wind to the site of the fe- 
male, and that they cannot orient themselves toward the female 
until they come by chance into a current of air carrying her 
emanations. 

When we tabulate the ratio of returns to the distance which 
the males had to travel, we get the following results: 


Experiment Number _ Distance Number _— Percent 
No. Liberated Miles Returned Returned 
= 19 1/200 9 ee 
_ Se ees 1/100 11 = 
2, 8, 4, 11, 30... 40 1/8 16 = 
eee 0 1/3 7 = 
5, 14, 15, 16, 18, 
ee eS eee _ 917 1/2 67 A 
13, 17, 31, 32, 37 ie a4 23 = 
Se 11/6 0 0 
ae Ps 11/2 1 
ee 13/4 7 ie 
Rs igs 2 3 : 
= 140 3 16 = 


120 Trans. Acad. Sci. of St. Louis 


Too many factors are complicated in these data to throw much 
light on the distance traveled and the per cent that returned. 
It would be interesting indeed if all the interfering factors 
could be eliminated, such as distraction of wild moths, shifting 
winds, ete., and a pure test could be made of the distance from 
which they are capable of detecting and discovering their mates. 
Surely everyone will agree that the return of 16 marked moths, 
or more than 10 per cent of those liberated in this test, from a 
distance of three miles is truly marvellous. Since this was ac- 
complished amid the aforementioned conflicting factors, it is 
logical to believe that their ability per se to pick up and follow 
a trail would far exceed this surprising distance. 

The table reveals the fact also that the experienced males, i. e., 
those which have made one or more successful flights to the 
roof, came back in a larger per cent of cases than did those out 
for their first flight. In 178 cases of the males taken out for 
the first time, 32, or 18 per cent, returned; in 557 records of 
males taken out that had previously flown to the roof one or 
more times, we got a return of 138, or nearly 25 per cent. This 
compares well with the results from cynthias, described else- 
where in these pages, in which we get returns for inexperienced 
and experienced fliers of 3014 and 37 respectively. In both 
species the difference between the two classes is 7 per cent. 

The hour of activity of the cecropias was always (excepting 
a few cases during bright moonlight or abnormal temperature) 
between 3:30 and 4:30 a.m. Even when the moths were liber- 
ated no further distant than our own back yard, and either 
early in the night or at 2:30 a. m., they showed no inclination to 
come in until 3:30, probably when the light stimulus began its 
work. At first thought the reader might suspect that the hour 
of dawn would vary considerably during the long period of 
experimentation, but while this would be true for any other time 
earlier or later in the summer, the hour of dawn just before 
and after the summer solstice is more nearly constant than at 
any other time during the summer. 

In summarizing the work on cecropias, we must not overlook 
the evidence gleaned from the behavior of moths deprived of 
the use of their eyes and antennae. We find blind males fiying 
to the females quite as readily as those with eyes uncovered. 


The Nuptial Flight 121 


TABLE No. 2 
SAMIA SECROPIA (MUTILATED) 
bo f?4 o1e@ 
g 8 é 3 Returns 
g Fel gi ele 
3 318 | 8s 2| 2le¢t 
o 8 be a 
“ae a 3 EE (42) 2| 3 le > 
8 g a bmi § o | & ay Te B aq 3 
Slug 4 o | & tel Mie EO 8 >1 A 
£ S |g ot gig i Sel scaewt gies 3 Fa 
B 1g |ED : aS) 33| | 3 \8s Re ee ae 
3 # | 8] 3 | ss) sel &| sige = #18/3 
eisai ll § 21 8 | eel eel 8) 8 ise a Bi e's 
BE }A|ER s FIP IA Oo 1 eT e ie a mlal|e 
{34 of each an-| | 
55 10| U| 9:14 p.m. |N.E.|Yes} %| 8 “tennae off I A 
“Blk. 
58* | 12] W/ 11:15 p.m.| W |Yes| | E.| 22 mt es thd 4 
th anten- 
59 12 | W.| 11:15 p.m. | W.|Yes| /s | E.| 11] 0} 1 ae com- |}0|}....| 0 
= = 
62 15 | W.| 11:30 p.m. |No Wind|1/50| W.| 18] 0| 18 dene Bia 6 
2 normal; 5 
| car eee oe. 
See mM. i PAS cstes antennae off; 
30 p.m. |No Wind/1/50} W.| 1 Bright of; 5 
left off. 
: 41:00 pan. By [Yea }-i/e: Wet 410 Boe ee as 0 
10:50 p.m. | S. | Yes/1/25} N.| 14] 0 aa pe 


“The 


..2Normal. cue ph pesealitneias ergo me — 

**Returns—1 normal; 1 with right off; 1 with left off; 2 with half of each off. 

In proof of their delicate sensitiveness, they came in response 
to the attraction of cynthia females after all cecropias were 
dead. We find the male cecropias flying home with one half of 
each antenna off, and to a slightly less degree with all of one 
antenna amputated, but none at all returned when both 
antennae were gone. See Table 2 above. 


Experiments on Platysamia cynthia. 


The cynthia moths began to emerge on May 14; the emer- 
ence was slow at the first of the season, only 8 individuals hav- 
ing appeared up to June 6. The period of emergence for the 
majority of the population seemed to date from June 7, so by 
June 10, sufficient material was on hand to make the first ex- 
Periment. Since these moths are native of the Atlantic States, 
One may carry on work in St. Louis, in the study of long dis- 
tance flights with the assurance that the marked males will not 
be attracted by females of their own species anywhere but in 
the cages on the roof. These moths, like the other species here- 
in studied, have aborted mouth parts and require no food; this 


122 Trans. Acad. Sci. of St. Louis 


eliminates the very difficult factor of proper nutrition of the 
organisms under experimentation. Enough factors remain, how- 
ever, to be considered in these studies,—age of the moths, the 
effect of the wind, weather, fog, moonlight, starlight, lamplight, 
urban odors, ete. Through and under these modifying influ- 
ences, we shall try to discover by what means these moths can 
orient themselves to their mates, and the extent of their abili- 
ties. 

Exp. 1. June 10. Wind, faint breeze from northeast; light 
fog; station, 4% mile southwest. By 11:30 the breeze had be- 
come almost imperceptible and the fog was dense. A dozen fe- 
male cynthias were displayed in wire cages on the roof. Eleven 
males, all 3 days old, were liberated at 9:14 slightly out of the 
path of the wind. Four of these returned at dawn. 

Exp. 2. June 10. Weather same as above; station, 4% mile 
east. Eight young males were liberated at 9:35 p. m. Two of 
these flew to the roof at 3:00 and 3:55 a. m.; the first was found 
resting quietly on a cecropia cage and the other alighted on a 
eynthia cage. 

Exp. 3. June 10. At 3 p. m., when I was painting num- 
bers on the wings of the newly emerged moths, one escaped and 
flew out the window and away, high over the housetops. At 
10:20 that night it came flying back to the cynthia cages as joy- 
ously as if it had not fled the spot a few hours before. 

Exp. 4. June 12. Wind, slight, intermittent breeze from 
west; station, 4% mile east. The 7 males included 5 unmated 
ones % day old and 2 mated ones, 1 day old. They were liber- 
ated in the park at 11:10 p. m. Only one returned, a previ- 
ously mated individual, at 12:20. 

Exp. 5. June 12. Wind, same as Exp. 4; station, 1 mile 
east. For this experiment, we used the 7 moths which had 
already come back from the former test flights and 7 new ones, 
all one day old. All were set free in the park at 11 p.m. Only 

one returned out of these 14; it was 5 days old and had made 
a previous flight, and it made this flight of one mile in three 
hours. At first it was thought that possibly the experienced 
fliers were too old, but since the only one to return was one of 
the old ones, it seems that other factors must have entered into 
the problem. 


The Nuptial Flight 128 


Exp. 6. June 14. During the afternoon, two male eynthias 
escaped while being handled, and promptly fled; at 12:20 and 
12:30 a. m. they came back. 

Exp. 7. June 15. Wind, not perceptible; station, 4% mile 
west. Twenty male cynthias, all less than one day old, were 
liberated at 11:10 p.m. Just one half of these, or ten returned; 
nine came in between 11:20 p. m. and 1:40 a. m., and one at 
dawn. I have not yet discovered a reason why these should be 
so much more agile in returning than were their brothers in 
apparently comparable tests. 

Exp. 8. June 15. Wind, imperceptible; station, 1 mile 
west. Eighteen unmated cynthia males, all two days old, were 
liberated. It is interesting to find that while in the last test 
50 per cent returned from 1% mile west, here 22 per cent re- 
turned from one mile in the same direction under the same con- 
ditions. The four returned at 11 35, 1:15, 2:05 and 3:40, the 
first one making the mile in 29 minutes. 

xp. 9. June 15. Time, place and weather, same as Exp. 
8. Five males that had already mated, four of them once and 
One of them twice, were also liberated one mile west, to see if 
mated males are less or more responsive to the lure. Only one 
returned, at 3:45. The numbers are too small to show anything 
excepting that the mated males appear in no way different, in 
ability or inclination, from the unmated individuals. 

Exp. 10. June 15. Wind, imperceptible; station, 1% mile 
north. On the same night of the eminently successful experi- 
ments just preceding, we tried liberating moths in the other 
directions of the compass. Twenty-four males one-half day old 
were set free 4 mile north at 10:58. Only one returned that 
night, at 12:45; two more came in the following night. 

Exp. 11. June 15. Wind, imperceptible; station, % mile 
east. These 22 young males, % to 34 day old, were set free in 
the park east of the house at 11:25. While 4 eventually re- 

ed, only one came in the same night, at 1:40, and can be 
Considered as really significant. Thus the returns from both 
of these last two directions were really negligable; in both ex- 
Periments the individuals were out long enough to come upon 
the trail by aimless wandering. i 

Exp. 12. June 15. Wind, imperceptible; station, 2 mile 
South. Under exactly the same conditions, 22 males were liber- 


124 Trans. Acad. Sct. of St. Louts 


ated 14 mile south. This lot consisted of 15 moths 114 days old 
and 7 which were 21% days old. None of the older moths re- 
turned, but 4 of the 114 day old ones came back, and all the 
same night, at 12:30, 1:23, 1:41 and 3:40. Here the proportion, 
18 per cent, would indicate that.this direction held some condi- 
tion imperceptible to us, which was more favorable to their re- 
turn than the north or east, but less favorable than the west. 
Of course my secret suspicions were that a current of air moved 
gently toward the west or sometimes south. 

Exp. 13. June 16. The foregoing experiments indicate that 
for some reason which I do not know the west is more favorable 
to the homecoming than any other direction. It seemed worth 
while to make one more attempt to solve this question. So at 
1:55 a. m. of the night of June 15-16, I took stock of my male 
eynthias, and threw all of my available material into one more 
test. There were in all 32 individuals, 14 of which had just 
come in from tests, and 18 which had emerged within the last 
24 hours. These were divided into two lots of 16 each and liber- 
ated in opposite directions, east and west, but at no great dis- 
tanee from the females. One lot, consisting of 7 young moths 
and 9 that had just come in from distant flights, was liberated 
50 feet east of the house. Since the indication was that the 
west was more favorable to their return, I handicapped those 
taken west by giving that lot a preponderance of young males, 
and I gave those liberated at the east point an advantage by 
assigning to their lot a greater proportion of experienced fliers. 
Of the 16 liberated 50 feet east, only one came back that night 
(after one hour and a quarter), and another came in the fol- 
lowing night at 10:55. 

Exp. 14. June 16. Conditions same as above. The remain- 
ing 16 moths, consisting of 5 experienced fliers and 11 newly 
emerged males, were liberated 50 feet west of the house. Of 
these, 6 returned the same night and 4 the following night. It 
is interesting to note that, although their normal period of 
activity was broken in upon by our interference at 11:55 p. ™, 
six of them extended their period of flight until from two to 
four o’clock, while those which laid over until the next night 
all performed at the hour of their own choosing, 10:55 to 12 
p.m. May it be that these four merely considered that aecord- — 
ing to ‘‘union”’ rules it was already quitting time when they 


The Nuptial Plight 125 


were set free at five minutes before midnight and sat down with- 
out even trying to come in that night? It is surprising that out 
of the 5 experienced fliers, two returned, while of the very 
young ones 8 came in. It seems to me that this experiment 
shows clearly that the one direction is far more favorable for 
the return of the moths than the other; if it is not the motion 
of the air that creates this response from a certain direction, 
then what is it? 

Exp. 15. June 17. Wind, southeast; station, 1% miles 
northwest. Twenty-six eynthias, 6 of which were 1% days old 
and 20 were less than one day old, were liberated near the path 
of the wind at a distance of 11% miles, at 10:52 p. m. Only one 
returned, aged 114 days, after a flight of 124 hours. 

Exp. 16. June 17. Wind, southwest; station, 34 mile north- 
west. Nineteen males, less than one day old, were set free at 
1l p.m. None of these returned. This lot was liberated in an 
ailanthus bush; this is the food plant of the caterpillars, and 
the insects upon emerging throw off the peculiar odor of this 
. tree; hence it might be that the odor of this tree had something 
to do with diverting their attention or confusing them. 

Exp. 17. June 17. Wind, southeast; station, 214 miles 
northwest. Twenty moths, 114 days old, were liberated in 
Forest Park at 11:25 p. m. Two returned from this flight of 
21 miles, one after only an hour and the other 41% hours. 

Exp. 18. June 17. Wind, southeast; station, 2 miles north. 
Twenty male eynthias, aged 1144 days, were taken to a point 
north, in Forest Park, at 11:35 p. m. One returned the same 
night, after 2 hours, and another did so the next night. 

Exp. 19. June 17. Wind, southeast; station, 1/5 mile 
northwest. For this experiment, all the cynthia moths on hand 
Were used. They were all held captive after having returned 
from previous flights, and their ages were as follows: 2 days 
old, 19; 8 days old, 2; 4 days old, 2; 17 days old, 2. These 25 
Were taken out a short distance, 1/5 mile, in the general diree- 
tion toward which the wind was blowing, at 11:50 p. m. Eight 
of this lot returned, the first after only five minutes and the 
last after two hours and six minutes. All of these eight were 
two days old, but, of course, these predominated in the lot. 

Exp. 20. June 20. Wind, southeast, station, 114 mile west. 


126 Trans. Acad. Sci. of St. Louis 


In the following group of five experiments, the male cynthias 
were liberated in the evening when the wind was blowing from 
the southeast and it continued in that direction until I returned 
at 4a. m.; there was no moon. Twenty moths, half of which 
had emerged that day and half the day before, were set free at 
9:30; none returned. 

Exp. 21. June 20. Wind, southeast; station, 34 mile north- 
west. Thirty-five male cynthias, 1% day old, were taken 34 mile 
northwest at 9:55. Twelve of these eventually returned, but — 
while all of them came in between the hours of 10:30 and 12:30, 
only one came in the first night (after 114 hours) ; 9 came the 
second night, 1 the third, none the fourth, and one poor wing- 
sore creature straggled in at midnight the fifth night. This 
experiment begins to bring to the fore the factor of rhythmic 
periodicity, which is a fairly well established character in the 
activity of this species. Their habitual] time of flight is between 
10:30 and about midnight; if they do not reach their goal by the 
end of this period, on the first night, they lay over for the same 
hours the next night or even the next. All of these had the 
opportunity to come in at either an earlier or a later hour, but 
not one of the twelve in this experiment did so. 

Exp. 22. June 20. Wind, southeast; station, 4% mile north- 
west. Thirty-eight male eynthias (20 one day old, and 18 two 
days) were set free at 10 p. m. Of these, 22 returned (11 from 
each lot) and, like the last ones, all came between 10:18 and 
midnight. All 22 came back the first night, or in less than 2% 
hours after they had been liberated 14 mile from the cages of 
the females. I do not think the moths in this experiment came 
back more quickly because they were a quarter mile nearer home 
than those in the last test, but probably because they were 
liberated in a current of air more direct from the house. Just 
half of these came in during the first half-hour, 10 to 10:30. 

Exp. 23. June 20. Wind, southwest; station, 1/5 mile east. 
The 38 males, aged 11%4 days, comprised two lots, 20 which had 
never mated and 18 which had mated only a few hours pre- 
viously. The purpose was two-fold: to get additional ecompar- 
ative data on the relation of distance to returns, and to ascertain 
if the mated or the unmated males respond more readily to the 
sex attraction. Of these 38, 20 returned, all but one, the same 


The Nuptial Flight 127 


night, and between 10:20 and 1:46. The first two came in in 
10 and 12 minutes, and 8 arrived in the first hour. One came in 
at 11:53 the following night. In comparing the returns of the 
mated and unmated individuals, we find that of the 20 unmated 
one, 12 (60 per cent) returned, and of those previously mated, 
9 (50 per cent) came back. This indicates that both are equally 
susceptible. 

Exp. 24. June 20. Wind, southwest; station, 50 feet east. 
By 11 o’clock a number of moths had returned from their test 
flights and were available for another. Since I dared not 
venture far from the house on account of the constant arrival 
of others, I took these, 18 in number, and liberated them in the 
front yard, only 50 feet from the cages, and almost in the 
direction from which the wind came. This happened at 11:07 
Pp. m., just in the time of the greatest activity of these moths. To 
my surprise, 11 returned, all the same night, but strange to say, 
in spite of the fact that they had only thrice the length of the 
room to travel, and they were set free at their most active 
Period, only one made the tiny journey in less than an hour; 
the others required from 114 to 3% hours to come in. Since 
7 did not come back at all (please remember that the females in 
Our cages were the only ones of this species in St. Louis), and 
Since they consumed more time than did those which returned 
from half a mile, the same night, it seems possible that they 
fluttered aimlessly until, in time, they came upon the trail not 
far away. Of course, as an alternative, one may, if one chooses, 
evoke as an explanation for the return of the latter, the theory 
that these moths profited by their recent experiences in coming 
to the roof, and that place memory aided them in making the 
return once more. I offer no argument in favor of either theory. 

Exp. 25. June 22. Wind, southeast; station, 4 mile south. 
The 27 moths used in this test included 10 less than one day old, 
Which had already mated, and 17 from 1 to 114 days old, which 
had not yet mated. These were liberated to one side of the 
direction from which the wind blew, at 9:50 p. m. None of 
these came back the first night, two of the mated moths returned 
the second night and one unmated one the third. Henee we 
must conclude that the ability of the moths to return under 
these conditions is negligible. = 

xp. 26. June 22. Wind, southeast; station, 42 mile east. 


128 Trans. Acad. Sci. of St. Louis 


These 21 male cynthias were unmated and from 1% to 34 day 
old. They were liberated in Tower Grove Park at 10 p. m. The 
results were practically the same as in the last test, wherein the 
conditions were similar; none returned the first night, and two 
arrived about 11 o’clock the second night. 

Exp. 27. June 22. Wind, southeast; station, north and 
slightly west, 4% mile. The 35 males were 1 to 114 days old, 
and 21 of them had already mated. They were liberated at 
10:08 p. m. in a large vacant lot 14 mile north, and a few rods 
west of the house. When I arrived home at 11 p. m., after 
attending to another experiment en route, I found the children 
in high excitement catching the moths; they had captured 12 
which had arrived before I did, so I have not the exact time of 
their arrival; 7 more came in before midnight, and 2 more came 
at 12:40, making a total of 21 which returned with speed the 
first night; none came on later evenings. The deductions are 
self-evident. This series of four experiments, 25 to 28, shows 
clearly that when the moths are liberated in the path of the wind, 
many return promptly for a distance of %4 mile; if out of the 
path, they are lost. When we compare the flight of the mated 
and the unmated males, both-of the same age, we find them prac- 
tically equal; 64 per cent of the mated individuals came in and 
57 per cent of the unmated ones. 

Exp. 28. June 22. Wind, southwest; station, 14 mile west. 
These male cynthias, 22 in number, unmated, aged 14 to 34 day, 
were set free at 10:35 p. m., to complete the series of tests from 
all directions being carried out this evening. For the third 
time we find that none came in the first night, 4 returned the 
second and 2 the third night, all during the usual period of 
flight of this species. 

Could anyone imagine experiments to behave so obligingly— 
to warm the cockles of the heart of even an entomologist—as 
does this series! Of the 70 moths liberated in the three direc- 
tions where the wind was unfavorable, not one returned that 
night, while of the 35 liberated near the path of the wind, 21, 
or exactly 60 per cent, came scurrying back, and more than 
half of them beat me home! 

Exp. 29. June 22. Wind, southeast; station, 1 mile west. 
This test was the same as the last, excepting the distance was 


The Nuptial Flight 129 


doubled. The participants were 9 unmated eynthias, 1 or 114% 
days old, and 12 which had made one or two previous flights. 
None of these ever returned. These five experiments, on the 
evening of June 22, wherein not one of the 91 moths liberated 
in an unfavorable wind returned that night, but a few came 
in later, somewhat justify our surmises in Exp. 24. 

Exp. 30. June 24. Wind, southeast; station, 50 feet west. 
The activity of the moths so far has seemed to indicate that the 
period of flight for this species is about two or three hours 
before midnight. To test this, 36 male cynthias were liberated 
in the back yard at 8:10 p. m., with the wind almost favorable 
for their return. This lot included 6 moths 1% day old, 22 
moths 1 day old, and 8 which had made a previous flight. Of 
these 36, 23 flew up to the cages on the roof; all but two did 
so before midnight, and those two came in only a few minutes 
later. None flew in immediately after having been liberated, 
although we know that they were fully capable of fifty times 
that distance if they would start at once. The first arrived at 
9:16, over an hour after liberation, and the others followed thus: 
9 to 10-8; 10 to 11—9; 11 to 124; 12 to 12:30—2. Since 
none at all came in before this period, although they had ample 
opportunity, and none after (I watched all night for more), 
we are safe in assuming that this is their chosen period of activ- 
ity. By chosen, we mean chosen either by them or by cireum- 
stances, by the combination of stimuli to which they are attuned 
to respond. Since these stimuli or combinations of factors 
usually oecur between these hours, the moths have the habit of 
staging their activities at this period, but if certain of the factors 
or stimuli to which they are attuned to respond are shifted to 
other hours, the moths change their program accordingly. But 
the point that is eternally puzzling to me is: why should the 
hour at dawn be the optimum time for the activity of eecropias, 
and two hours before midnight be likewise the optimum time 
for flight for these near relatives, whose other habits are very 
Similar? : 

The proportion of returns in the various lots of moths is of 
only secondary interest in this experiment, but the data may as 
Well be recorded for use elsewhere. Of the 6 moths, 4 day old, 
2 came in; of the lot of 22 which were 1 day old, 16 returned. 
Of the 8 experienced fliers, 4 had made one flight and 4 had 


130 Trans. Acad. Sct. of St. Louis 


made two flights previously. It is interesting that of those 
which had made one flight 1 returned, while of those which 
had made two flights, all four returned. This juicy morsel of 
data tempts one to rumination, but we had better refrain in 
this case, for this is probably only a matter of chance in dealing 
with small numbers. These five did not come in among the 
earliest, but just along with the others, from 9:35 to 11:07. 
Thus 33 per cent of the youngest moths came in, 77 per cent of 
those 1 day old, and 62 per cent of the old fliers. In all, 28 
moths, or 64 per cent of the number liberated, returned; this is 
_ strikingly similar to the per cent (61) that returned from the 
front yard, the same distance in the windward direction. The 
chief difference lies in the fact that the latter were set free in 
the midst of their active period and still took a longer time to 
come in. 

Exp. 31-3144. June 25. In the previous experiment we have 
seen that when male cynthias are liberated early in the evening 
they become active at about 9 o’elock, and the activity lasts until 
about midnight. In the cecropias, the similar period of activity 
is from 3:30 to 4:30 a. m. Experiments have shown that when 
cecropias are liberated early in the evening, they do not fly to 
the females, but wait for dawn.* Conversely, one would infer 
that if one liberated cynthias after their normal period of activ- 
ity had ended, they would not fly to the females’ cages that 
night, but would hold off flight until the following night, so 
they could fare forth at their usual hour. To put this question 
to test, the following cynthias were liberated in the early morn- 
ing hours, after their normal period of activity had ended for 
that night: 6 males, 114 days old, which were liberated at 2:45, 
and 18 that had come in before midnight, after having made two 
previous flights, which were set free at 3:15, in the back yard 
in a favorable location. Of the 6 young males liberated at 2:45, 
3 returned, at 3:20, 3:24 and 3:27 a. m.; of the 18 experienced 
fliers, 11 returned between 3:22 and 4:15. This reveals at once 
that these moths do not postpone their flight until the next 
night, when liberated after their usual period of activity 1s 
past, but modify their habits and come in at some other time. 
In this they differ from the cecropias, who, for the most part, 


*With very few exceptions. 


The Nuptial Flight 131 


stick doggedly to their usual program, excepting under unusual 
counter stimulation. But more than this is evident from this 
experiment. The first moths were liberated a half-hour before 
the second lot, yet they did not come in from the yard a minute 
Sooner, but simultaneously with the latter. Now the dawn was 
just beginning to break at 3:20, and during the next ten min- 
utes, the first 7 of these moths of both lots came in. May it be 
that, while the emanations of the females are the primary 
inducement to arouse the males to activity, yet a secondary 
stimulus may exist in light of a certain intensity, or meteorolog- 
ieal conditions, or some such factor, to which also they are 
delicately attuned and to which they respond? In later experi- 
ments, recorded in the following pages, wherein tests were made 
within doors where conditions could be watched all the time, 
these moths showed, night after night, a periodic activity before 
nine o’clock, which brought all of the males to the window. 
This window, facing the street, admitted a subdued light from 
the street lamps, park lights and passing automobile lights. The 
full light of day streaming through this window did not elicit 
any response from the moths, but after a period of rest during 
the daytime and after nightfall, at about 8 o’clock, they pres- 
ently flocked to the window. My opinion is that this mellow 
light from the various sources was very nearly akin to the light 
at break of dawn, and the moths react to both in the same way. 

Exp. 32. June 27. Wind, southeast; station, 50 feet north- 
west. Previous experiments show that the male cynthias fly 
to the cages of their mates when the moon shines brightly. This 
test was now repeated, with the same wind and distance, 50 ft., 
on a dark night. 52 males were liberated in the back yard at 
10:20 p.m. The moon was completely darkened by clouds. I 
harvested the returning moths until midnight, and since, by 
that time, I had sufficient data to show that he lack of moon- 
light is no deterrent to their activity, I went to bed. They 
began to come in a few minutes after their liberation, and up 
until midnight, 17 had arrived. 

Summary. 

Although tabulation loses much of the evidence yielded by the 
individual experiments, such a summary gives one a grasp 0 
Some aspects of the work as a whole. 


No. 3 
CYNTHIA MOTHS 


Liberated E 3 Returns E 
colt er 
= & & 
3 2 3 S E 5 Fa g 3 
a § : ee tel a te lalelal (ate 
2 en | aot 
ae - Sie es fale les] g lale|al2] jae] 
tar) é & s 8 or) by So a Z% A Hes 
PT] PVA ata] Taba elite] ala tala 
l E 3 & gr Be] Ba 8 m| 83 
Bp Fs Es es ALE ee Peele ete te Z 
1 10 U 9:14 p.m. Fog N.E Yes % Mile| 8S. W. | 11 il 3 BS hr sie Exad Weise 4 Mi Aone 
2 10 U ae p.m, Fog N.E No ¥ Mile E 8 8 APB ee a Cee LUAU ON Ga fiae pubes cs 2 Pe eee 
eT. te u {| pope {ee Poa hie ia 1 ay eh an Weta 
Po Nae aon (Ser wl ve lismmel wn lat 7} ol «a lad t..... rae |W Ag ee 
Slight M2-5 
5 12 U 11:00 p.m Wind WwW. Yes 1 Mile E 14 7 7 Ul bh 4 a Oe eae PS Pg Cent : 
6 14 U ne EE ER a eo Be ys (eae 2 CHO elds wa bee Hy Ve Wie'e a tdvaeblets nace: ae ake” alld VERE Le 
7 15 U Thm be oak! No Wind|No Wind| 1 Mile Ww 20 |} 20 0 par, ad te | aia Rca TOR Bete 01 A, Cs a Wi Maps 
8 15 U Rie PM ly kas No Wind|No Wind] 1 Mile Ww 18 18 0 >” TAC DE Saud (BERND Uns Le? sepseg ss  ea Mi he eM eas 
9 15 M See Be Eee is | No Wind|No Wind} 1 Mile WwW 5 Oats! DN pak Wa kipern 1 b Apa) atone 
10 15 U SES Was Fo No Wind|No Wind] % Mile N 24 24 0 % PAE een ees 3 By Ralls 
il 15 U REG Bums foes ce. No Wind|No Wind Mile E 22 | 22 0 4-34 2 Le ae 4 yeh Cane 
12 15 U BEE Te Ls i No Wind|No Wind Mile 8 22 22 0 tt eee ee | Re. OM Doe dees Pen ey Wea an 4 res ee 
Mow. eb thea |... No Wind|No Wind| 50 Feet} E. |16 | 7 | 9 |........ ia Te an ee a ae AAO 
14 16 U TAS Aim. bo. cs No Wind|No Wind] 50 Feet Ww. 16: 2 Buch. yor 6 [Sam oer 2 
mel | oj 108epm.|........ E. 134 Mile] N.w.|26 | 26 | of) Sot iba dtp, Tg ae oe aS 
ne Ol ittpe 1... c Ge. | Xen se Mile | Now. | io | 20 |°0 | M-S¢ I..;..].....00..00100.. nig WA ee eee 
17 i U Ase OA hh ses 8. EB Yes (|2}4 Mile] N. W. | 20 | 20 0 % yes epee (May (oN raed 2 ae (ae 
18 17 U S26 eM 1. 5 a. 8. EB ° 2 Mile N. 20 20 0 1% B BD eee & 2 BASS hee 
19 17 U See Dam ly es. a 8. BE. Yes 4% Mile | N. W, | 25 0 25 |See Exp.| 8 Be be vans 8 
20 20 U 9:30 p 8. BR. No wee Mile Ww. 20 20 0 -1% CARER ie a Gece 
21 20 U Brae Bate he ee 8. E, es 4, Mile| N. W. | 35 35 0 1 9 1 1 12 pa Eee 


6él 


T 38 {0 wg ‘pooy ‘suv.y 


StN0 


ae 


wh ee toe 
ao XNdSn 
aa ae 


ae 
qaaa Soe 


RM MDM 


mmr ne 


. 


46yq wudny oy 


€&T 


134 Trans. Acad. Sci. of St. Louis 


It will be seen in Table 3 that in the 32 experiments, 683 
male cynthias, which had emerged from their cocoons in the 
laboratory, were taken out in various directions and liberated 
at various distances, ranging from 50 feet to 214 miles. Out 
of this number, 214, or 31 per cent, made their way back to the 
females on the roof. Of these, 180 came in the first night. 

Let us first summarize our data on the return of the moths in 
favorable or unfavorable winds—that is, winds which blow from 
the caged females toward the males, and those which do not. 
Exp. 16 is omitted from this summary for the reason given 
elsewhere and only those moths which came in the first night are 
considered, because the later ones were subject to varying winds 
which could not be traced. 


Favorable Wind. 


Liberated Distance Returned Per Cent 
50 feet 58 45 
31 1/8 mile 14 45 
63 1/5 mile 27 43 
80 1/2 mile 44 55 
85 3/4 mile 1 3 
37 1 mile 6 16 
26 11% mile 1 4 
20 214, mile 2 10 
420 153 36 

Unfavorable Wind. 

Liberated Distance Returned Per Cent 
34 50 feet 12 35 
8 1% mile 2 25 
138 14 mile 6 4 
21 1 mile 0 0 
20 14% mile 0 0 
20 2 miles 1 5 
241 21 9 


Here we see that out of 420 moths liberated in favorable 
winds, 153, or a little over 36 per cent, returned, in contrast to” 
less than 9 per cent of those in unfavorable winds. However, 


The Nuptial Flight 135 


we must be cautions about accepting these figures on their face 
value, because, we must admit, this latter per cent is made up 
largely by those which returned after a few hours from the 
dooryard. 

When we consider the per cent of returns in relation to the 
distance traveled, these figures throw little light on the subject. 
Of course it is to be expected that the number of returns would 
decrease as the distance increases; these figures give only a poor 
indication of this, because of the complication of other factors. 

Since I do not wish again to beg the question, I shall leave to 
the reader the problem of explaining the results of the series of 
experiments conducted on June 15, when there was no wind 
that I could feel, hear or detect. In this group of tests, 84 moths 
were liberated north, east and south of the house, of which 7 
(8 per cent) returned; of 59 liberated west of the house, 21 
(36 per cent) returned. Those on the west, moreover, were 
handicapped by an additional half-mile distance. There was 
obviously a marked difference in favor of the west on this 
occasion. 

The ability, or rather the inclination, of the males that had 
already mated, was tested to see if they would again respond to 
the attraction of their mates. They appeared fully as eager and 
Successful as the young moths. Of 56 liberated for this special 
Purpose, 26 (46 per cent) returned. This is fully as good a 
showing as we could expect from any group. : 

There are some indications in the data that those moths which 
have made one or more previous flights to the roof stand slightly 
better chances of making another trip, or of making it in less 
time, than the inexperienced fliers. From the table it will be 
Seen that of the 683 males liberated, 581 were taken out for the 
first time, and 102 had made one or two previous flights. Of 
the former, 176, or 30 per cent, returned, while of the 102 
experienced fliers, 38, or 37 per cent, came back. However, here 
again, we must be cautious in the interpretation of these totals, 
because a closer examination of the data reveals that the greater 
number of experienced fliers chanced to be liberated in ve ca 
winds; this advantageous factor might easily account for the 
slight difference in their favor in these totals. Some of the 
individual experiments gave stronger evidence for the superior 


136 Trans. Acad. Sct. of St. Louts 


ability of the moths on their second or third flights, but well 
balanced tests with large numbers will have to be made before 
we can safely arrive at conclusions. And even if we find that 
the moths liberated for the second or third time are more suc- 
cessful or prompt in returning, the discovery only brings us 
face to face with a more profound problem, viz., are they more 
successful because they actually profit by their experience, or 
because of a finer sensitiveness and superior ability? In other 
words, is their superior ability inherent or acquired? 

The hour of arrival of each of these 214 cynthias was recorded. 
It seems that each of the four species of Saturniids observed 
has a period of flight each night which is constant for that 
species. 

A summary of the cynthia records reveals that for this species 
there are two periods of activity, a primary period from 9 p. m. 
until slightly after midnight, and a secondary one which runs 
from about 3 a. m. until a little after dawn. The peak of their 
activity (see Table 4) is from 10:30 to 11. Of course it is true 
that, early in the term of experimentation, when we had not 
yet fully discovered these habits of flight, we probably inter- 
fered with the natural program of these moths by liberating 
them too late in the evening for them to make their flight 
naturally that night. In a similar event, the cecropias merely 
waited until their regular period the next night, but the eynthias 
were very likely to respond to the call at their second period, 
about dawn. The first is probably their normal period of activ- 
ity, but I am strongly inclined to think that the second is in 
some way influenced by meteorological or dawn conditions. A 
fuller discussion of this complication of primary and secondary 
stimuli will be taken up in the later pages on periodic activity. 

It is interesting to compare the various amounts of time eon: 
sumed by the different moths in making the returns from various 
distances. The records show the exact time for each one of the 
214 males which returned, and the distance traveled. In con- 
sidering the data we must not overlook the fact that where the 
moths did not return before dawn of the same night, since they 
are not active during the day, they had to wait for the darkness 
of the second night; so when the records show that a moth was 
out for 28 hours, it does not mean that this length of time was 


The Nuptial Flight 137 
TABLE No. 4 
HOURS OF FLIGHT, CYNTHIA MOTHS 
M. A.M. 
4 eo. 1 o1-S 
% 2/8/8/8|/8/8le 

= | SS be ees Set ie Oe et eee 
z at olo] 9] ols |e] oi] 8 it ole 61 6461 o7.6.1-5 
oo af ee eS colo colo PS Oe oie we tant oe ace = - 3 - 3 
ms Si81|S 1812) 2/2182] Sissi Sts g 213 
SES ElE/E/E/SlSlSlSlS fal Zl 2] Sl 212] Sis] slé 

l 3) 114 
; bey # 
: i 

4 . i 1 
é i 1 
z See es 2)°3) 1 a whee oT 
. td Pe Seay hele aa 
: a1. 1 
” i 1 

Returns 

2nd Night me 2 
Ses 6 i 1 
Returns 

2nd Night 2 ‘ 

3rd Night i 

12 i |. Ee Gee 1|: d 

° oe SSD 

m ight 

2: Nick ; a 4]. , 
. ight eeeele 
aaa vee a ee ‘ 
As i 

mee Night oe ee 
a i} 3i- al. 1 
Gd AS if 

oy cL 3 See oe 

3rd Night : 4 - 

We Sieh | ieee ia a ot 
5 22 iil 41-41 LF £1 : 
wet. roe eee ee 

aad Night |. rE ete Re Sip, Ge Hs © re an ee 
ae. ot a} #2 3 oe A oe 

|: tte $434 ie Abi 2 
, 7. 1-2) SU BLA oe atesclecen| & 
oy MG dake eg Ge GS ee metal & 
ee a eee ee ee ee Pe ee ee Be ae 
oes Byala} ey] af i] app che pate feeeedonned 
31 Vitec hiaeeges +e a obew bene © ES, 1 
po gee des mae eae Re af 6) ifsc u 
Pe Pod ar te Hake anes Pah, ele Or edlesedorg pera] aT 
al weeebeees] 5 | 3] 19 | 41 | 30 | 24] 25/161 71101 51. 8/i5| 5} 11214 


spent in search of the mate, but it does show that after an 


interval of perhaps 21 hours for sleep, the moth was st 


responsive enough to the lure to rise up and finish the quest. 
* The period of absence of the entire 214 moths was tabulated, to 
facilitate comparison of the groups which traveled different dis- 
tances. The period of absence was marked off into hours for 
the first night; beyond that time the action of the moths was so 
complicated with unknown factors as to defy analysis. 


138 Trans. Acad. Sct. of St. Louis 


Time o0feet Yemile Ymile 3%, mile 1 mile 214 miles 
0-1 hr 35 14 34 0 1 0 
1-2 hr 21 13 19 1 bE 0 
2-3 hr 14 4 6 0 2 1 
3-4 hr 1 0 0 0 - 0 
4-5 hr 0 0 1 0 2 1 
5-6 hr. 0 2 0 0 0 0 
6-7 hr 0 1 0 0 0 0 
7-8 hr. 0 4 0 0 0 1 
2 night 6 5 12 9 0 2 
3 night 0 0 2 1 0 0 
6 night 0 0 0 1 0 0 
77 39 74 12 7 5 


Experiments on Telea polyphemus 


On May 7, I had on hand four polyphemus males, from 1% 
to 4 days old, but no females had yet emerged. The cecropia 
females were on the roof, however, and the wind was blowing 
through their cages toward the east. At 6:30 p. m. these four 
males were liberated in the park 225 yards east, to see if they - 
would respond to a sister species. None of them came to the 
windows. The same test was repeated on May 20, with two 
young male polyphemus. These were taken 1% mile east when 
there was no wind stirring; they too were lost. These two 
preliminary tests can hardly be classified with the experiments 
on polyphemus, since they were only to ascertain if this species 
is attracted by the females of a related species. These individ- 
uals showed no evidence of such a response. 

Exp. 1. May 21. Wind, northwest; station, 14 mile south. 
By this time I had two female polyphemus on the roof. At 
7:30 I liberated 7 males, from 1 to 3 days old. Two days later 
at 11 p. m. one moth, the youngest one, came in 

Exp. 2. May 22. The first native palyphectis male le 
peared at the cages on the roof at dawn. 

Exp. 3. May 22. Wind, northwest; station, 2 miles south- 
west. Seven males, aged from 1 to 24% days, were liberated 
two miles distant. None returned in this favorable win : 

Exp. 4. May 23. With 3 females on the roof, 3 native 


The Nuptial Flight 139 


males arrived during the night, at 11:10, 11:35 and 12:08 re- 
spectively. These arrivals seem to be correlated with the ap- 
pearance of the moon, and the details are discussed elsewhere. 

Exp. 5. May 26. Wind, east, station, 1 mile west. With 
half a dozen female polyphemus in cages at the window, I lib- 
erated 10 males (6 aged one day, 2 aged two days, 1 aged 
3 days and 1 aged 11 days) one mile west of the house. The 
wind was blowing from the house toward the males. Four of 
the 10 returned, one after 214 hours and 8 the next night, 
after an absence of 24, 25 and 28 hours. On this moonlit night 
their actual time of arrival was 11:38 p. m., 1:10, 1:50 and 4:10 
a.m.. During the period of dawn two native males also flew in. 

Exp. 6. May 27. Wind, east; station, 134 miles west. Five 
native males which had come to the roof were liberated at 10:50 
p.m. One came in at the following dawn. 

Exp. 7. May 27. Wind, east; station, 1% mile east. Three 
males, all one day old, were liberated in the park, in a most 
unfavorable position in regard to the wind. To our surprise, 
after an hour and forty minutes, one returned. Another was 
picked up by a schoolgirl next morning, two blocks south of the 
point of liberation. 

Exp. 8. May 27. Wind, east; station , 144 miles east. Two 
native males, one old and one young, which had recently come 
in, were set free at 11:10 p. m. One of these wandered in three 
nights later, during the dawn hour. 

Exp. 9. May 28. Wind, southeast; station, 3 miles north- 
west. When the cecropias were taken out for their long dis- 
tance test, 19 polyphemus were also liberated. Four were bred 
Moths 1144 days old, and 15 were captive wild males. Not one 
of these 19 ever returned. Of course the ceeropias did scarcely 
better; only one came back, and that tardily. : 

Exp. 10. May 29. The night was clear, with the wind 
blowing from the east; at 9:00, the moon arose and remained 
bright. At 11:20 three native polyphemus flew in. At mid- 
night the moon became hazy, and soon dark. Three more came 
in with the cecropias at dawn. This again shows that their 
flight is not confined to one brief period of the night, as the 
cecropias, but these flew for a short period before midnight and 
again during the dawn hour. Whether these periods are deter- 


140 Trans. Acad. Sct. of St. Louis 


mined by rhythmic activity or by light stimuli (moonlight and 
dawn) cannot yet be determined. 

Exp. 11. May 30. Wind, east; station, 14 mile east. Three 
native males which had come in at dawn were liberated at 9 
p. m. in this unfavorable wind; none returned. 

Exp. 12. May 30. The moon shone all night, and the wild 
moths came in at the following hours: one each at 11:00, 11:40, 
11:55, 12:01; 12:05 and 3:15. Here again their activity is 
centered in the two periods, the midnight and the dawn hour. 

Exp. 13. June 1. One more wild male came in at dawn 
with the cecropias. 

Exp. 14. June 1. The moon that night was half obscured 
in a haze. One native polyphemus came in at 11:45, and 8 more 
during the dawn hour. This, added to the evidence of previ- 
ous nights, certainly indicates two periods of activity in the 
night, the same as the sister species. The wind was blowing from 
the south, and all these moths came in from the north. 

Exp. 15. June 6. During the dawn, one native wild poly- 
phemus flew to the roof. There were 6 cages of female 
ceeropias there, but no polyphemus; the only females of their 
own species in our possession at the time were on a table inside 
the laboratory. The arriving male spent no time on the roof, 
but flew in at the open window and went directly to the cage 
of females of his own species on the table. 

Exp. 16. June 10. One native polyphemus came in at 
dawn. 

Exp. 17. June 15. Wind, imperceptible; station, 4 mile 
north. The 8 bred males used in this test were 4, 2, 1 and % 
days old. They were liberated at 10:58 p.m. Only one of these 
returned ; it was 2 days old and came in with the cecropias the 

following dawn. 


Exp. 18. June 18. Despite the fact that the female poly- 
phemus had been displayed constantly, since June 10 no native 
males had come in until this morning when at 2:20 one came 
and alighted on the cage. There were cages of female cynthias 
all about, but this male made no mistake in his selection. This 
is probably the end of the polyphemus season. 


The Nuptial Flight 141 


Summary. 


Polyphemus males did not show any reaction to the many 
cecropia and cynthia females on the roof. No males, either 
native or bred, ever came to the roof excepting when females 
of their own species were present. During the period of ex- 
perimentation, May 21 to June 18, 31 native males came in and 
went directly to the cages of their own species only. 

Tabulation of all the data* reveals that out of the 64 marked 
males that were liberated at various points, only 9 returned to 
the roof; 7 of these were inexperienced and 2 had had previous 
trips. On a percentage basis, we find that 10 per cent of those 
taken out for the first time and 8 per cent of those that had had 
previous experience, returned. These figures are too small to 
be significant, excepting that they indicate faintly that experi- 
ence is of no advantage. Of the 9 that did return, 4 came in 
during the first night, 3 the second night and 2 the third night. 

Tn the small number tested for long distance flights, even in a 
wind which seemed favorable to them, none returned from a dis- 
tance of 3 miles, or even 2 miles, but some did come back from 
¥, 1, 1%, and 134 mile points. The above evidence gives one an 
idea of what one may expect when more extensive work is done. 
It must be borne in mind that polyphemus are native to this re- 
gion, and undoubtedly many of our marked bred males flew to 
native females. Throughout the season the native polyphemus 
males did not come to the roof in such abundance as did the 
cecropias. We do not know whether this is because these moths 

9 not occur in such large numbers as the sister species, or 
Whether they are not responsive to the third-floor condition, 
which is probably above the normal level of their flight. 

The time consumed in making the trip to the roof from dis- 
tances varying from 14 to 34 miles varied from 1% to 40 hours. 

The normal time of flight of the eecropias was found to be 
(with a few exceptions under certain conditions) the hour of 
dawn; for cynthias, a period in the middle of the night and 
again at dawn. This species also has two distinct periods of 
activity, the hour before midnight and the hour of dawn. The 
hour of arrival of the 39 males, both native and bred, which flew 
to the roof, was as follows: 


ee 
*See Table 5. 


Trans. Acad. Sct. of St. Louis 


TABLE No. 5 
POLYPHEMUS 


| ul 2 ‘ Bg ge re : 
aured 7843 ‘Ag PAQBN : — Nn : : : — OA Orr ie _ 
IN} $197 q31 feet Pn Sata 
cosa Tagg oe 5 BP gs ceo a eee nee) eng eee 
44a ee tg ee ee ee ear: 
ang peneg main oe ee ene ee eee 
18301 Ho lol ww mmole lillian: e 
z WU3IN PALL SS Fs ee ee 
5 : Se ae ee 
a VUSIN Puocoseg —— ee ies ss 
ZUBIN 3sIL om Brea? nt ar 
me ae aes eats tet oe ere 
S20 8 BERR: Paes a 
skeq ‘o8y os (ARR fee Dt bisa 
rye Spe Pa sl Lili isiine 
pee Ge eee 
S}YBILJ SNOT sae ae : 
-AdIg PVH IY, Joqunyy 21 fe ae a 
oulLy, eee 
WILT JOJ NO Joquiny inet ae ey Wg sere hae 
Pepezegry qunN & ae So MMNe ‘MH Bor o: x 
a ere Zs ee 
euloy] Woy UOTeIIG, i od (og Beigi i : = 
. Ae 
82) Ur 90 s : 
TAL Ur eouezstq, hs - ce See Ss e 
ae 
ee “3: g goog :o: 
AIASIOATT PUTAL g& ‘eo AA Oe 
eee co 
um, cog eat eS Eines Oo 
Wor PUTA is ge lee at z 
me ee S 
sotek ee oa 
o 11: § $898 '8::::8 
"JA ‘qd ‘UOneieqry jo uly, Be! pr Sane a) . S 
i _ See CS) a OP ea a 
‘ON quouttedxyy a It MH SCHHSOUAGSSSRA 
a SNR 8 AS arr 
Dap 
ea | 2 Bee 2 222R2 3 
S Sea 2 Aaaae EEEEEE 2 


The Nuptial Flight 143 


11:00 to 12:00 11 
12:00 to 1:00 4 
1:00 to 2:00 2 
2:00 to 3:00 : 
Dawn, 3:20 to 4.30 21 
Total 39 


Thus the two periods of activity are apparent at a glance at 
the figures. In certain experiments there was evidence that the 
activity of these moths was correlated also with the moonlight, 
and that perhaps these moths are more susceptible to the moon- 
beams than are their sister species. Further tests and reactions 
in this line will be discussed in later pages. 


Experiments on Callosamia promethea. 


Because I could not always be on the roof in the late after- 
noons to study the flight of promethea, my notes are fragmen- 
tary, but are sufficient to get the time of flight and to show the 
trend of activities in these moths. The cages containing the 
females were placed both on the roof and down in the back yard. 

Exp. 1. June 1. Wind, southwest; station, 1 mile north- 
west. The 9 male prometheas (4 bred and 5 native) were liber- 
ated in Forest Park at 5:05 p. m., in or near the path of the 
Wind from the house. Four of the 9 returned promptly, making 
the distance in 10, 11 and 12 minutes and 1% hours. The first 
3 were native ones which had voluntarily flown to the roof be- 
fore, and the last had emerged in the laboratory. 

. 2. June 10. The day was rainy and without wind. 
At 9 o’clock a fog formed, which was very dense by 11 :30 p. m. 
Oceasionally there was a trace of breeze from the east or north- 
east. At 9:14 3 marked males one day old were liberated % 
mile southwest of the house. None returned. 

. 3. June 10. Wind conditions same as m Exp. 1. 
Seven males were liberated in the park 225 yards east of the 
house. Five of these were aged 1 day, one 4 days and one 5 days. 
One, aged one day, came in with the cecropias at dawn. Let 
Me state here, before the reader formulates fascinating theories 
about the moth that came in at dawn, instead of its usual time 


144 Trans. Acad. Sct. of St. Louis 


before dusk, that this was the only one in any of the experi- 
ments to come in at dawn. It is easy to speculate that, since 
one promethea came in at the dawn period when cecropias 
usually fly, that phylogenetically the prometheas once had the 
same habit as cecropias and now occasionally revert to it. 


Exp. 4. June 15. At 11:30 p. m., I liberated 26 male 
prometheas 100 feet west of the house, to see if they would 
break their set habit of flying before sunset and come back to 
the cages of the females during the night. Eighteen of these 
were 14 day old and 8 were 2 days. None came back during the 
night or the period of dawn, but, true to their colors, 12 came 
back at the appointed hour, between 4 and 5 p.m. Of those 
which were 1% day old when liberated 50 per cent (9) came in, 
and of those 2 days of age, 27 per cent (3) returned. The 
strongest point here is that, while they were only 100 feet away, 
they did not bestir themselves to come until their accustomed 
time, seventeen hours later. 


The foregoing work on the prometheas does little more than 
to show that their time of flight is shortly before the close of 
day. Records of the bred and native males showed their period 
of flight to be as follows: 


3:40 to 4:00 
4:00 to 4:20 
4:20 to 4:40 
4:40 to 5:00 
5:00 to 5:20 
5:20 to 5:40 
5:40 to 6:00 
6:00 to 6:20. 
6:20 to 6:40 


peo OoONPANAH Ow 


Total 33 


It is at once apparent that of these 33 males which came in 
before sunset (we have socially ostracised the one who so far 
ignored conventionalities as to come in at dawn!) the majority 
eentered their activity about 4:20. It is exceedingly strange 
that promethea should fly by daylight; at present I know of no 


The Nuptial Flight 145 


other Saturniid species that does so.* Here then is excellent 
material for experimental studies in rhythmic periodicity. 
The tests have proven that it is possible for the bred as well 
as the wild prometheas to fly to their mates from a distance of 
one mile, and in surprisingly short time too—ten to twelve 
minutes. When part of the cages were placed on the ground, 
they came to those on the roof just as readily as they did to 
those on the ground. I have never seen these moths come in 
during the rain, but I have seen them come in between showers. 


*Fabre gives a few instances. 


PART II. 


EXPERIMENTAL STUDIES ON ODOR, WIND AND LIGHT 
IN RELATION TO RHYTHMIC PERIODICITY 
IN SATURNIID MOTHS. 


INTRODUCTION. 


In part I of this paper, we have already seen how a tiny mass 
of flesh and blood ealled a Saturniid male braves the elements 
and overcomes nature’s obstacles for a distance up to three 
miles to reach another mite of flesh and blood, the female 
Saturniid. In the coming together of these two masses, space is 
annihilated, and we seem to get a combination which is rivaled 
only in the chemistry laboratory. I say ‘‘seem to get’’ advisedly, 
because these moths possess sense organs which surely must 
function in a way that is not analogous to anything in the 
chemistry laboratory. 

While to most organisms we accede five senses, in the case of 
the adult Saturniid moths we must eliminate the sense of taste. 
So here this organism traveling so actively toward its goal can 
be credited with possessing the olfactory, auditory, tactile and 
optical senses. Some or all of these four senses function, either 
in distant or proximate orientation. _ 

What is the vehicle of the stimulus? What do these four 
sense organs brush up against as this tiny organic mass shortens 
the space between itself and the object of its flight? The at- 
mosphere, and the vibrations which transmit light, sound and 
possibly other sensations of which we are not aware, since We 
have no organs to receive them. The atmospheric currents and 
gases, oxygen, nitrogen,* ete., are capable of bearing odors ; 
which ean be received by the olfactory organs. Vibrations 
transmit the light of the moon and stars, light of various de- 
grees of intensity from the sun, and in the city where the ex- 
periments were conducted, light from street lamps, houses and 
automobiles. These, presumably, can be perceived by the optic 
organs. Sound vibrations as a means of communication are 


*In the heart of a city, many other gases and impurities. 


Experiments in Rhythmetic Periodicity 147 


similarly. transmitted. We know from the experiments of 
Turner that Saturniids posses auditory powers, but we have no 
reason to suspect that they would function from great distances, 
although they might be of service in locating the female at close 
range. Other vibrations, akin to radio or wireless or in fact 
akin to the vibrations upon which our known senses function, 
are also carried on the atmosphere or ether. That such vibra- 
tions, as yet unknown to us, should function in bringing to- 
gether the sexes, we neither affirm nor deny, but until experi- 
mental proof is offered, we place the burden of proof upon any- 
one who wishes to argue in their favor. So of the four familiar 
senses, there are two, olfactory and optical, that seem to function 
for distant orientation, and possibly two, tactile and auditory, 
for proximate orientation, the latter, of course, in addition to the 
olfactory and optical senses. 


Now when you have at one end of the line a mass of matter 
which shows an affinity for another mass at the other end, and 
this affinity is made manifest through the functioning of cer- 
tain sense organs, the masses cease to be so much inert or non- 
conscious matter, but become at once living, psychically en- 
dowed animals. Since this organism does respond to lights, 
odors, winds, ete., to the fullest extent of its being, it would be 
Well to see experimentally if it is only a tiny mechanism that 
blindly reacts to environmental conditions, or if in a large num- 
ber of them under observation, some individuals might display 
Something akin to selection or emotions. 


The experiments recorded in Part II were performed for the 
purpose of trying to discover by what means the males do find 
the females from a great distance, as the preceding pages have 
revealed they really do, and also to discover if the females are 
anything more than mere bodies of odoriferous substance which 
Passively wait the coming of the males. In Part I, I hav casi 
covered to my own satisfaction that wind, odor and hoege — 
ditions of light are the environmental requisites for their com- 
ing together ; in Part II, I shall try to show experimentally 6 
they have the ability to perceive odors borne on the wings of the 
wind, and that they perceive light vibrations, and react to them 
in various ways, according to the make-up of the individuals. 
This combination of perception and reaction to stimuli, mm con- 


148 Trans. Acad. Sci. of St. Louis 


nection with the rhythmie periodicity of each species, leads one 
into entanglements which are not easily solved. 

It would be best, therefore, before giving details of the ex- 
periments, to give a brief resume of the work that has been done 
on the rhythmic periodicity of organisms. 

‘Living matter is rhythmic; it is always doing something at 
intervals; these intervals often seem to have no relation to out- 
side influences, like breathing or the recurrent beats of the 
heart, but in many cases the intervals of the acts correspond 
with the cosmic changes. Night and day control sleep; the tides 
have a marked influence on the habits of many of the shore liv- 
ing invertebrates, and so ingrained are these periodic habits that 
they are retained even when the animal showing them is re- 
moved inland and kept in a perfectly still aquarium. Summer 
and winter, seed time and harvest play perhaps the greatest 
role in this rhythm. One has only to think of the breeding 
habits of most animals, and the annual appearance and disap- 
pearance of the foliage of deciduous trees to recognize this.’’ 
So says Arthur E. Shipley, in his introductory chapter of 
‘‘Life.’’ In a later chapter on Rhythm he interestingly touches 
upon various kinds and types of rhythms in both the animal 
and the plant world. He writes on the rhythm of cells, rhythm 
of parts of cells, rhythm in tissues, rhythm in organs, rhythm 
in organisms, and rhythm in communities. 

Our general interest in the present work is rhythm in insects, 
and especially in moths. In Shipley’s work there is no mention 
of this for moths. Bouvier has a chapter in his ‘‘Psychie Life 
of Insects,’’ entitled ‘‘Vital Rhythms and Organie Memory,’’ 
and while there is little mention of night and day activities of 
moths, he does discuss the work that has been done on rhythms 
of insects and other invertebrates from the time of Reaumur to 
the present day workers. 

Charles Elton, in his Animal Ecology, tells us that many 
animals in a community never meet, because of the fact that 
they become active at different times. This is because the 
environment is subjected to a number of rhythmical changes 
which result in corresponding variations in the nature of the 
animal communities at different times. There is a day and 
night rhythm which affects both free living animals and some 
parasites. This rhythm may be of practical importance, and 18 


Experiments in Rhythmetic Periodicity 149 


most strongly marked in the deserts. There is not always a 
Sharp limit between day and _ night communities; in polar 
regions there is no night fauna, and in the tropics the latter is 
very rich. 

Such night and day changes are found not only in free living 
animals, but also exist among parasites of mammals and birds. 
Owing to the fact that most mammals sleep regularly either by 
day or by night, there exist corresponding rhythmical changes 
inside their bodies, especially in temperature. In both birds and 
mammals, the body is slightly colder during sleep. This rhythm 
depends entirely upon the activity of the animal, since nocturnal 
birds like owls have the normal rhythm reversed (i. e., they are 
warmer at night), and this in turn can be reversed by changing 
the conditions under which they live so as to cause the birds to 
come out by day and sleep by night. There are certain nematodes 
parasitic in man which show the effects of sleep rhythm in a 
very remarkable way. The first species (Filaria bancroftt) lives 
as an adult in the lymphatic glands of man in tropical countries, 
but its larvae live in the blood. In the daytime these larvae 
retire to the inner parts of the body, mostly to the lungs, but 
at night they issue forth into the peripheral circulation, appear- 
ing first about 5 to 7 in the evening, reaching a maximum about 
midnight and disappearing again at about 7 or 8 o’clock in the 
morning. This reaction can be reversed if a person stays up all 
night and sleeps in the day, which shows that the round 
worms’ activity is affected by the rhythmical changes in the 
conditions of the body like those described above. Another 
Species of Filaria (loaloa) has larvae which live in the blood of 
man, but unlike the other species, these larvae come out only 
In the day, disappearing at night. It is stated that this perio- 
dicity is not affected by reversal of sleep, but presumably it 
must originally have been caused by some rhythm in bodily 
environment. Manson-Bahrn* mentions a third species which 
has larvae in the blood, which occur in the peripheral circulation 
equally by day or by night. 

The habits of these worms have a very important bearing 
upon the means of transmission from one man to another; 
F. bancrofti is transmitted by blood-sucking mosquitoes which 


eee 
*Manson’s Tropical Diseases. 


150 Trans. Acad, Sct. of St. Louis 


fiy at night, while loaloa is transmitted by Tabanid flies which 
bite by day. 

Most animals have more or less definite migratory movements 
during the twenty-four hours of the night and day, and in some 
eases these are regularly rhythmical but not necessarily cor- 
related exactly with light and darkness. The result of these 
movements is to alter the composition of animal communities in 
any one place. Sanders and Shelford* found that among 
animals of a pine woods there was a certain amount of diurnal 
migration in a vertical direction. For instance, one species of 
spider was to be found among low herbs at 4:30 a. m. and 
among shrubs at 8:30 a. m., while another species occurred in 
trees at 4:30 p. m. and in herbs at 8:30 p. m. 

The distinction between day and night communities is not 
necessarily a sharp one. The length of dusk varies throughout 
the year; in England it is longest in midsummer and mid- 
winter, and shortest in spring and autumn. Again the amount 
of light at night varies regularly with the moon and intermit- 
tently with cloudy weather. In fact, the distinction between day 
and night communities may turn out to be less marked than we 
might at first suppose. 

In polar regions there is no such alternation of day and night 
except during spring and autumn; and since during these times 
the temperature is too low or the ground too snowy to support 
animal life, the species living there are nearly all typical day- 
light ones. Conversely, below a certain depth in the sea, or in 
large lakes and in subterranean waters, and inside the bodies of 
animals, there is continual darkness, so the animals living there 
also form homogeneous and permanent communities. Sometimes, 
however, the bodies of animals reflect the rhythm of their 
outer environment, and cause corresponding differences in thelr 
parasitic fauna. Probably the most conservative, smooth work- 
ing and perfectly adjusted communities are those living at @ 
depth of several miles in the sea, for there can be no rhythms 
in the environment such as there are on land.’ 

As we pass from poles to equator, the night fauna begins to 
appear and becomes gradually more elaborate and important, 
until in such surroundings as are found in a tropical forest it 


*Ecology 3:306. 


Experiments in Rhythmetic Periodicity 151 


may be more rich and exciting and noisy than the daylight 
fauna. Tropical day and night are always twelve hours long 
throughout the year, while the night in southern England or 
northern United States is only eight hours long in midsummer. 


Very little is known on the day and night rhythms of moths 
and butterflies. | With Lepidoptera collectors almost outnum- 
bering the Lepidoptera, it does seem strange that all we know 
about these activities is that moths fly at night and butterflies 
in the daytime. But this information is not sufficient. A day- 
flying moth is not in flight during all of the daylight hours, and 
neither is a nocturnal moth thus active throughout the night; 
each creature has its hours of activity; what are these hours 
for each species, and why are these certain hours chosen above 
all others? In behavior work this is an important point. For 
instance, Turner’s careful work on behavior in the hearing of 
Saturniid moths with its excellent conclusions probably would 
have given him even better results if he had considered for each 
Species its natural period of activity. It is logical to expect that 
the reactions of the moths would have been different during their 
hours of intense alertness and activity than during their period 
for slumber. 

Regarding the material now in hand, we have stated in the 
previous pages that the cecropias become active during the hour 
of 3:30 and 4:30 a.m. The polyphemus are abroad from 3:20 
to 4:30 a. m. and from 11 p. m. until midnight. The prometheas, 
for no reason which we have yet fathomed, choose to fare forth 
at 3:40 to 6:40 in the bright daylight, while the cynthias are 
active from 3 a. m. until dawn, and from 9 p. m. until mid- 
night. Other observers have found the period of activity for 
allied moths to be as follows: Mayer, too, finds the prometheas 
active between 2 p. m. and sunset. According to Fabre, the 
reat peacock moth requires the dusk of the early part of the 
hight, 9 to 10:30 p. m., while the lesser peacock requires the 
brilliant light of the middle of the day. The banded monk or 
oak-egger flies between 3 and 6 in the afternoon. C. M. Weed 
Says that cynthia moths occasionally fly on cloudy days. 


Before we can determine that rhythmic periodicity per se ie 
Controlling factor in these moths, we must first eliminate t : 
reactions that are purely sensory. There is nothing we can eal 


152 Trans. Acad. Sct. of St. Louis 


purely rhythmic if the response can be attributed to sensory 
reaction. The following experiments will help clear up this 
point. 


Experiments to Test Perception of Odor. (Cecropia). 

The results of the long-distance experiments justified the 
assumption that the odor of the females is carried by the wind 
and is perceived by the male some distance away. The follow- 
ing close-up experiments were made to test this theory. 

Exp. 1. May 18. At dawn many male cecropias came to 
the roof. Thirty-nine of these were placed in the glass box.* 
The temperature was 68° F. In an hour they were all quietly 
settled; then I gently placed two females (each in a small wire 
eage), aged 4 and 8 days, in the box. This change elicited 
absolutely no movement on the part of any of the individuals 
of either sex; all rested so quietly that they appeared in pro- 
found sleep. The females were not expected to be aggressive, 
and the males may have been fatigued after their long morning 
flight over the roof-tops to reach the cages. At 7:17, after a 
lapse of 17 minutes, the young female began slowly to move 
about, then suddenly vibrated her wings in a very excited man- 
ner. Within a very few minutes, two males nearest her cage too 
became thoroughly excited. As she continued rhythmically 
vibrating her wings, another small group in the opposite dark 
corner began to show activity. (The glass box was at this time 
covered with a heavy blanket, which was lifted from one end, 
thus admitting the dim light of a cloudy day. The males were 
all near the dark end of the box, and the females in the center.) 
As the fluttering of the few males at the dark end continued, I 
thought they would settle on the cages of the females in the 
center of the box, but therein I was mistaken; all those which 
were aroused to activity fluttered past the females and on into 
the light portion of the box, and there fluttered violently up 
and down, bumping their heads against the glass. When the 
females rested a few minutes later, I counted eleven males 

ing against the glass at the light. The males, ar : 

from quiescence at the dark end of the box by the agitation © 
a thirty- 

glass 


*This glass box used throughout these experiments was 
two-gallon yreetnenh with glass sides and iron bottom; either 4 
or an opaque cover could be improvised as desired. 


Experiments in Rhythmetic Periodicity 153 


the females, all flew past the females, ignoring them en route, 
and crowded to the light. Not all the moths behaved alike ; 
only 11 out of the 39 responded thus. This may be explained 
by the fact that this was an off hour for their activity, or by 
the hypothesis that physiologically and psychologically, the 
moths show individual differences. This demonstration shows 
beautifully that it was not the females per se that aroused the 
males, but the odor that emanated from their bodies after they 
had begun to vibrate their wings, and the reaction of the males, 
after having been aroused by the circulating odor, was to fly 
to the light. There were still 28 males that remained unaffected 
at the dark end, the same area from which the 11 active ones had 
come. Why did they not respond? I placed the two females 
in their individual wire cages in the midst of this group, but 
they failed to stir. I prodded the young female with a pencil 
and soon she became intensely active again, vibrating the wings 
rapidly. This aroused to activity some of the 28 males near her, 
and almost simultaneously the eleven at the lighted end, which 
had been quiet for a time, renewed their agitation, rapidly 
vibrating the wings as they moved up and down the glass and 
beat their heads against the barrier. 

Before this one young female had vibrated for one minute, 
three of the 28 males left the crowd and joined the eleven at 
the light end of the box. These were quickly followed by other 
males, and when she quieted down after two and one-half min- 
utes of vibration, there were only 14 left at the dark end of the 
box. Even during the ten minutes following, 6 more males 
responded to the disturbance and flew to the light side, leaving 
only 8 unaffected by her influence. I tried again to prod her 
to activity, but there was no response, perhaps due to fatigue. 
So here were 31 out of 39 males responding to the excitement 
created by this female becoming active and beating the air with 
her wings, while all had been stolidly indifferent so long as she 
had remained quiet and there had been no circulation of air in 
the box, although she was very near to them. The males did 
not all react at the same time; some responded to the stimulus 
Promptly, and others much more slowly. This may indicate 
that some of them were out of the path of the circulation of 
the air at first, but it seems to me more likely that some males 


154 Trans. Acad. Sci. of St. Lowis 


are less sensitive, and hence harder to arouse than others, The 
fact that some males were aroused almost simultaneously with 
her first wing movements, and at the end 8 were still indifferent 
in the same environment suggests a wide range of individual dif- 
ferences in a very essential character in the life of the species. 
These males were native moths which had flown into the 
laboratory at dawn that morning; in the next experiment we 
shall study a similar phenomenon with males bred from cocoons 
in the laboratory which have had no outside experience; hence 
any possibility of the interference of fatigue will be eliminated. 


Exp. 2. May 29, 11 p. m. In the glass box I placed 41 
male ceeropias which had emerged in the room; 14 were 4 to 4 
day old, and 27 were from 1 to 1% day old when they were 
placed in the box at 11 p.m. Since the males in the last experi- 
ment had shown such positive reaction to the light after having 
been awakened by sex excitement, it was decided to test these 
for their reactions to the light alone before introducing the 
females into the game, to see if after spending a period in 
absolute darkness they would react to light rays when no female 
odor was present. The whole box was darkened by covering 
with several layers of blankets and roping these about the table 
legs so not even a pencil ray of light eould penetrate from below. 
At 10:10 the next morning, I found 32 males precisely where I 
had left them, and 9 had wandered about a bit. This little 
incident shows of course that if they become active each night 
at stated hours because they are instinctively attuned to do so 
(rhythmic periodicity), then all or the majority of them would 
have changed their positions, especially since during this period 
of confinement in the box (from 11 p. m. to 10:10 a. m.) they 
passed through this time when they are usually active. Hence 
in the absence of light or sex stimulus, their rhythmic perio- 
dicity failed in this case. 


When the blankets were folded back from one end of the box, 
at 10:10 a. m., one male immediately became active, and after 
ten minutes ae more were wildly fluttering the wings; these 
three moved to the light end, while two more at the rear (dark) 
end slowly moved their wings up and down. This is the sum 


total of the activity of 41 males for a period of 30 minutes after 


Experiments in Rhythmetic Periodicity 155 


the mild light of the room was admitted at one end of the box. 
I then created another period of darkness by covering them 
securely for 35 minutes. The cover was lifted again, and during 
a period of 30 minutes not one of the 41 males had moved an 
iota. All of the males were then shifted, as gently as possible, 
to the rear end of the box, and a wire cage containing five young 
females (aged 144 days) was placed at the light end. One 
female proceeded to slowly open and close her wings, and during 
the following ten minutes five males flew to the light end and 
beat against the glass wall. Then a second female began to 
vibrate her wings, and in five minutes three more males came 
out of the dark end and joined in the excitement at the light end 
of the box. With the activity of the males very near to them, 
the excitement of the females ran high. If one suspects that 
cecropia females are entirely devoid of emotions and that they 
mate only by virtue of being passive bundles of odoriferous 
substance, let him watch a group of females placed as these 
were near a group of excited males. First one and then another 
would flutter or vibrate the wings with great rapidity for a 
few minutes; this was followed by a wave of intense excitement 
on the part of the males—one is tempted to call it an agony of 
desperation. The females in their little cage were near the 
light end this time, instead of in the middle as before, and the 
males paid more attention to them than they did in the last 
experiment, and many attempts at mating through the wire 
were made. Strange to say, the females were the more agressive 
in these attempts. At noon the excitement was still high, but 
by 12:15 all had subsided to quietude, with 12 out of the 41 at 
the light end of the box. 
Thus these five females were able to arouse only 12 out of 41 
young males in this ease. This is a much smaller proporiion 
than in the last experiment. The cause of this difference remams 
@ question; there are several possible reasons. First, our day- 
time is their midnight, and we could not expect them to be 
active during their normal period of rest. Second, the males 
may have been too young to be as sensitive and responsive at 
this early age. Again, these had emerged in the laboratory and 
had never had any out-door experience with either the extremes 
and variations of light and darkness, or in responding to the 


156 Trans. Acad. Sct. of St. Louis 


female emanations. This would imply that experience aids and 
augments instinct in this activity—a hypothesis which we men- 
tion but shall not champion at present. Lastly, the moths used 
in this experiment were a random sample of the population, 
that is, all that emerged from a certain lot of cocoons, while the 
males in the preceding experiment had in a way selected them- 
selves from the whole population of wild cecropias in having 
found their way to the roof the first time from the wilds; in 
this preliminary test any of their brothers who were too weak 
or stupid, or did not possess the delicate sensitiveness to respond 
to the call of their mates were of course left behind in the 
woods, so those which responded so obligingly for us in the last 
experiment had really been selected by Nature for this very 
activity, and had proved their ability. This latter condition 
appeals to me as a more plausible explanation for the difference 
in the response of the two groups of males than either of the 
two former factors. This difference in the reaction of the two 
lots of material here shows clearly the danger of drawing sweep- 
ing conclusions from material of unknown history. Here two 
lots of material, outwardly alike, have psychological states, and 
possibly also physiological foundations, quite diverse. 

Exp. 3. This is a continuation of Exp. 2. At 12:15 p. m. 
the females were removed and the box darkened with blankets 
in the usual way. For seven hours the cage was left so, and at 
7:10 p. m. the south end was uncovered. There I saw all of the 
moths in a state of profound quiet, apparently asleep. The 
room was lighted by a 50-watt lamp hanging from the ceiling 
twelve feet away, and in front of the uncovered end of the box. 
When the curtain was lifted a few of them started to flutter 
about, and after ten minutes seven of them had assumed activity 
of some sort. In 25 minutes, this number had not increased. 
This surprised me, because they had now had a long period of 
rest, and instead of midday it was almost night, the time when 
one would expect them to be aroused easily, even without arti- 
ficial stimulus or the presence of females. 


The males, now all quiet, were placed at the dark end of the 
box, and at 7:50 a wire cage containing 8 healthy females was 
placed in the light end. The females remained quiet, . 
motionless, and after three hours only 6 males had worked their 


Experiments in Rhythmetic Periodicity 157 


way to the light end. At 11:10 I approached cautiously and 
fanned a current of air over the cage of females and toward 
the males in the dark end of the box. Almost immediately many 
wings began to quiver, and in five minutes 13 more had 
wandered to the lighted pane. The fanning was continued only 
at intervals, but up to 8 o’clock no more had responded. This 
shows that the males may remain in the presence of female odor 
plus light and only 6 out of 41 stir in three hours, whereas in 
female odor plus light plus breeze, 13 more respond within five 
minutes. But in this test again where moths bred in the labora- 
tory were used, more than half of the males failed to react at 
all. How is this to be explained? Are these laggards the stupid 
ones which Nature would eliminate in the wi 

Exp. 4. June 3, 2:30 p. m. Thirteen young males were 
gently placed in the box with 32 females; all were quiet at the 
time. Heretofore, the females when placed in the glass box had 
been enclosed in a wire cage, but this time they were all placed 
together free. For 45 minutes there was no reaction of any kind 
by any of the moths of either sex. Then I began to fan the 
group gently with a folded newspaper; after about five minutes 
of this a few males awakened to gentle response, and then two 
females; in ten minutes more, five females were participating in 
wild fluttering, and three of these had done just as the males 
in previous tests had done in fluttering to the light end of the 
box, and there beating their heads and wings against the glass 
nearest the light. Whenever their activity lessened or ceased, 
a little fanning would quickly arouse them to renewed activity. 

This experiment shows, as did some of the previous ones, that 
some females do show aggressiveness, react to light vibrations, 
and possibly also are influenced by the emanations of the op- 
posite sex, just as are the males. 


Electric Fan Experiments. 


In the foregoing experiments we have seen how, ordinarily, 
quiet moths are not influenced to activity by the presence of the 
opposite sex in close quarters until a breeze, either artifically 
induced or naturally ereated by the flapping of wings, dissemin- 
ates the odor. The following supplementary experiments were 
made upon moths of both sexes in separate cages placed before 


158 Trans. Acad. Sct. of St. Louis 


the steady stream of air from an electric fan. These tests give 
us data on: (a) the reaction of male moths when placed before 
an electric fan, (b) the reaction of female moths when placed be- 
fore an electric fan, (c) the reaction of male moths when fe- 
male odor was blown upon them, (d) the reaction of female 
moths when male odor was blown upon them. Since each of 
the experiments gives data on more than one of the above four 
points, it is not possible to classify the work under the above 
headings, but the experiments are given in the order in which 
they were undertaken. 

Exp. 5. May 30, 12:30 p. m. A cage containing 10 male 
cecropias and one male polyphemus was placed in front of an 
electric fan, which was set to the slowest possible speed to throw 
a steady flow of air. All these were native males that had come 
in with that morning’s dawn. For fifteen minutes they were 
subjected to the slow, steady stream of air from the fan. There 
was absolutely no voluntary action or reaction on the part of 
any one of the males during this period. The motion of the air 
would sometimes force a wing to one side for a moment, but 
there was no voluntary movement. The only reaction, if it may 
be so called, was that the males clung the more tenaceously with 
their tarsi to the meshes of the cage. The fan was turned off 
and they were given a rest of 15 minutes. 

When the fan was turned on again, a cage of six females, from 
one to two days old, was placed half way between the fan and 
the cage of males, in such a way that the breeze would pass 
through it before reaching the males. After just two minutes 
of the rain of this tainted air on the erstwhile motionless males, 
3 began vibrating the wings with intense rapidity, and in five 
minutes the male polyphemus was fluttering wildly about (for 
a cecropia female!) and another cecropia joined in the activity. 
During this period of ten minutes there were four other males 
which made, not a frantic demonstration, but a gentle move- 
ment of the wings up an down. There were only two which 
showed no response to this modified air, whereas a little while 
before none of the lot showed even a slight response to a breeze 
of the same intensity of pure air. When the fan was stopped, 
the moths soon became quiet; after a ten-minute rest the war: 
rent of air was renewed, very gently; this revived their activity 
and within five minutes all but one male showed some reaction 


Experiments in Rhythmetic Periodicity 159 


to this stimulus, either by flying about, fluttering or waving the 
wings. 

To again see if they would act in the same manner in a 
breeze of clear air of the same strength, I gently removed the 
cage of females from the path of the breeze. There was no 
period of rest given the males between these two trials, but 
when they were in their greatest activity the cage of females 
was gently slipped away. It was interesting indeed to see that 
in just three minutes, eight of them became quiet, and in two 
minutes more the other two subsided. And so they continued 
motionless, even when the breeze gently pushed a wing this 
way or that. After a quarter of an hour, the cage of females 
was again pushed between them and the fan, and within five 
minutes three males were in a state of excitement. The fact 
that the response was not so general this time may have been 
due to one of three things: the males may have been fatigued ; 
they may have become accustomed to this stimulus to which 
they could not normally respond while imprisoned; or the wind 
from the fan may have had a cooling effect on the pores or 
organs of odor of the females and reduced their efficiency. 


This experiment substantiates the results from the glass box 
experiments, and the theory that the males come great distances 
to reach the females by following the odor on the wind. This 
test indicates also that not all males react in the same way, but 
while this seems to be so, we must be cautious about saying it 
with too much positiveness because with our crudely improvised 
technique it seems quife possible that the odor-laden air was 
not equally distributed over the entire cage. These reactions, 
please remember, were not made at the hour of their natural 
time of activity, which is early dawn, but at high noon, which 
is their midnight. These males were wild native ones which 
had come to the females on my roof; it would be interesting to 
see what responses we would get from males which had emerged 
from their cocoons in the laboratory, in other words, a strictly 
random sample, unmodified by experience or selection. 

Exp. 6. May 30. 6:25 p. m. This experiment was made 
upon 18 males which had come in at dawn of the day before. 
The fan was placed three feet away, and a stream of pure alr 
was thrown upon them. After ten minutes of this treatment, 


160 Trans. Acad. Sct. of St. Louis 


there was no movement or any other indication that they were 
aware of it, just as in the previous experiment. 

A cage of ten females from one to two days old was gently 
inserted between the males and the fan; after five minutes, 
six males were opening and closing their wings. After a few 
minutes, four of these relaxed and only two remained active, 
one of which escaped and flew out the open door. Not content 
with the slowness of their response to the magnificent treat 
which I was offering them, I suspected that through poor tech- 
nique much of the odor was missing the mark, or more likely, 
was being carried through the cage of the males too quickly. 
Therefore I built a wall of books and boxes behind and beside 
the cage, so this air could be retarded and would accumulate. 
Two minutes after this change was made, several of the moths 
began to vibrate their wings, and five minutes after the wall 
was done, five males were beating their wings in intense excite- 
ment, and all were struggling against the side of the cage facing 
that of the females. Of course, it appeared that they were 
pushing their way toward the source of their excitement, but 
we must consider also that the window was in that direction, 
so it may well be that, after having been aroused by the odor 
stimulus, they were struggling to go toward the light, as the 
moths did in similar circumstances in the glass box. After 
seven minutes of this arrangement, six were active; after 13 
minutes, eight were excited, and since no more of the 18 showed 
signs of responding, the experiment was concluded. Thus re- 
tarding or piling up the tainted air caused eight to become 
violently active, whereas in the first part of the experiment, six 
(four of which soon relaxed) made only a languid response. 

Exp. 7. This is really a continuation of Exp. 6, excepting 
that the sexes were reversed in their, position before the fan. 
Heretofore the females had always been so placed that they 
received only the pure air direct from the fan, untainted by 
male odors. The reactions of the females, when the pure air 
passed through their cage, was exactly the same as it was 
for the males under similar conditions. Their only reaction, 
if it might be called such, was to cling the more tenaceously to 
the meshes of the cage. The wind often pushed a wing to one 
side, but there was no voluntary response on the part tf 
single female to a current of pure air. 


Experiments in Rhythmetic Periodicity 161 


Now the cages were shifted, so the air was blown from the 
males upon the females. Within a few seconds after the ex- 
change of positions, the hitherto active males quieted down in 
the breeze of pure air and remained motionless; the females, 
now placed in the stream of air from the males’ cage, just as 
readily showed response. Within two minutes, four of the 
ten, heretofore stubbornly indifferent, became violently active, 
and in five minutes two more gently responded. The others 
remained unmoved up to the conclusion of the experiment 
ten minutes later. 

This experiment shows clearly that some of the females do 
respond to the odors of the males, and the proportion of these 
compares well with the proportion of females which responded 
when the air was agitated by fanning in the box experiments. 

Exp. 8. June 3. The material was 12 male cecropias which 
had come in that morning at dawn, and 22 from the previous 
Morning. The two cages were placed side by side, with two 
cages of females from one to three days old between them and 
the fan, as in previous eperiments. However, before the females 
were placed there, the stream of pure air was permitted to 
Play upon the two cages of males for an hour. During all 
this time there was not a quiver of response, although at seiaeig 
the strong breeze deflected the wings. Almost immediately 
after the two cages of females were placed between the males 
and the fan, there was very active response among the 22 males 
which had come in the day before; this activity soon developed 
into a very excited flapping and fluttering, and was partici- 
pated in by almost all of this group; this riotous excitement 
lasted for fifteen minutes. The 12 moths in the other a 
which had come in at dawn that morning, were strangly differ- 
ent; despite the fact that they shared equally the wind as it 
came from the cages of the females, and despite the fact ae 
their cage touched that of their neighbors where they could 
undoubtedly hear, see and smell the activity, there was abso- 
lutely no reaction on the part of even one ma e. I si at a 
loss to explain this exceedingly strange behavior; if at sind 
not for the fact that other males responded to such stimuli in 
experiments conducted during their first day in the laboratory, 
One would conclude that the fatigue of the flight that morning 
had made them numb to sounds, odors, etc, whereas those 


162 Trans. Acad. Sct. of St. Louis 


which responded had had a longer period in which to rest. 
However, this lack of response gives us some evidence in an- 
other problem. In going over the experiments, one might ex- 
pect that activity in some cases might be due to imitation, that 
the activity of one moth in a group influences the rest to 
motion, that movement to light or odor might not be due to 
light and odor per se, but merely to sharing a neighbor’s excite- 
ment by imitation. Here we see 12 males remaining immovable, 
even in close juxtaposition to 22 very active ones. This indi- 
cates that each male asserts its prerogative of being a separate 
entity, physiologically and psychologically, and reacts only when 
he himself is ready. 

Exp. 9. In this experiment, the positions of the cages were 
reversed and the actions of the 20 females observed. When the 
pure air was passing through their cages, they made absolutely 
no response of any sort. As soon as the cages were transposed 
and the air from the males came upon them, there was a 
startled stir; for five minutes three females quivered their 
wings, then there was not further action although the breeze 
was continued for twenty more minutes. Thinking that pos- 
sibly the wild life that these males had led might have depleted 
their attractiveness, and not knowing how old they were, I re- 
moved these two cages of wild males and put in their place 
two cages containing 27 males that had emerged from their 
eocoons in the laboratory two days before. For forty minutes 
the breeze from these was blown upon the females, but not one 
would stir. Here too it is apparent that the response to stimull 
is not extraneous, but occurs only when the individual insect 
is ready physiologically. d ; 

Exp. 10. This was not a set experiment, but certain acecl 
dental discoveries were made on the wind, odor and mating 
which should be recorded here. They seem to show that wind is 
necessary for proximate as well as distant orientation ; in other 
words, even though the male is close to the female, the wind 1S 
a factor in bringing them together. oe 

On June 3, at 6 p. m., 26 wire dish covers, each containing s 
male and a female from 114 to 3 days old, were arranged on y 
table back in a corner of the room. I needed a number 0 
fertile females for another experiment, and J thought, of eee 
I could get them in this way. Mating usually oceurs ™ ©" 


Experiments in Rhythmetic Periodicity 163 


early hours of morning. The next morning I was surprised 
to find that only six pairs had mated, and four of these pairs 
were at the edge of the group of cages nearest the open window. 
On another occasion when six young males were placed with 
32 healthy females in a large box with close-fitting glass lid 
so all circulation of air was excluded, only one pair mated. 
In contrast to these incidents, a cage on the roof blew over one 
morning, and in a very short while, before the females had had 
time to fly away, they had all mated with the native males 
which were coming in. These accidents seem to indicate that 
close proximity of the two sexes is not in itself sufficient to 
bring about the union unless a eireulation of air plays upon 
them and assists them in locating each other. 

Exp. 11. This too is only a group of observations pertinent 
to the subject in hand. That each of the five species of 
Saturniids has a specifie odor. no one will deny. The odor of 
any one species is perceptible to the human olfactory organs, 
but if a difference exists in the odor of the two sexes of each 
Species, it will take a very acute sense to distinguish between 
them. The following notes, meager as they are, will throw 
some light on the subject. 

On May 6, when I entered the laboratory, I immediately per- 
ceived a strong cecropia odor, although there were only fifteen 
moths of both sexes there, and five windows on the east and 
west walls were all open. This shows the heaviness of the 
odor and its staying qualities. From this time on it was no 
uncommon thing for the members of the family, when on the 
Street in front of the house, to catch a strong whiff of cecropia 
odor on the breeze. Moreover, on several occasions when they 
Were out riding, they would pass through a ‘“‘streak”’ . 
cecropia odor in the atmosphere; in these cases the odor seemed 
actually to form a distinct, clear-cut stream through the air, 
like the Gulf Stream through the Atlantic. My wife sniffed the 
limits of one such stream and found it, according to = 
olfactory sense, to be about fifteen feet wide, and distinet 
enough that she felt sure that she could have followed it ard 
against the breeze to its source if the traffic on Pennsylvania 
Avenue had not been so heavy at that point. Of course she 
had no way of knowing whether the moths were near or far. 
This characteristic form of dissemination of the odor is of im- 


164 Trans. Acad. Sci. of St. Louis 


portance in an understanding of the quest of the male. If 
the odor were light and volatile, and diffused in all directions 
equally, like ripples on a pond, there would be little chance 
for the male to locate the source. The course followed by the 
moths in approaching the roof where the females are gives 
slight indication of the nature of these emanations. Sometimes 
the males would approach from a distance flying near to the 
ground and only when near to the house would they turn their 
course upward and over the edge of the roof; at other times 
they could be seen for some distance flying at the level of the 
second-story roof, 

At one time the only females that we had out on the roof 
were those which had hatched from the New York cocoons, yet 
for several days the native Missouri males flew to them in great 
numbers; this would indicate at least that the odor was not 
noticeably different in the moths. from two widely separated lo 
calities. Of course, one would only expect that geography would 
make no difference in the odor glands of the moths, but so many 
queer things happen in nature, and so many unexpected factors 
have come to light in the details of the present problem, that I am 
glad of the opportunity to know positively that Nature sub- 
stantiates our expectation in this matter. 

When many cages containing female cecropias were on the 
roof and there was more choice for the males, they spent much 
more time fluttering and hesitating before alighting. Early in 
the work when there were only three cages of females at the 
window, the flight of the males was very direct, but when the 
odors emanated from a dozen cages scattered over the roof, the 
males had difficulty in choosing the desirable cage. Quite often 
they would spend from two to five minutes fluttering about the 
roof, apparently in confusion. In several instances the males 
were seen to fly in a straight line past the roof and a few feet 
beyond; then, apparently discovering that they had gone too 
far or at least lost the trail, they turned squarely around and re- 
traced their wingsteps to the right place. ae 

There were on the roof at one time three cages contaiming 
polyphemus females, but not one of the cecropia males ever made 
the mistake of even alighting on one of these. Likewise, z 
though polyphemus males came to the roof oceasionally, they 
did not rest on the cages of the other species. The relationship 


>» 


Experiments in Rhythmetic Periodicity 165 


between cecropia and cynthia is closer, for there was an inter- 
specific attraction and on one oceasion a mating. Other investi- 
gators have found it possible to cross cynthia and cecropia and 
get fertile eggs. 

Exp. 12. Everything so far points to the probability that the 
males find the females through odor perception. The problem 
whether certain females are more attractive than others to the 
males remains open. If odor is the medium of attraction, it 
seems to me that the degree or intensity of odor would be to a 
great extent regulated by the age of the female. With this in 
mind, the following tests were made on cecropia: 

Six cages were arranged in a row (see figure 1); each con- 
tained 10 females, whose ages were as follows: . 


Cage 1, 1%4 day old. Cage 4, 4 days old. 
Cage 2, 1 day old. Cage 5, 5 days old. 
Cage 3, 3 days old. Cage 6, 6 days old. 


The cages were placed in the path of the wind, and be- 
tweeen 10 p. m. and 4:30 a. m., 26 males flew to them. They 
did not always remain on the cage which first attracted them, 
but they were counted as being attracted to the cage upon which 
they finally rested. The following table shows how many males 
were attracted to each cage: 


Cage Age Males Cage Age Males 
1 Vy, 3 4 4 6 
2 1 i 5 5 4 
3 3 2 6 6 0 


Thus the males clearly decreed that in their estimation the 
females which were one day old were the most attractive, while 
the antiquated females were spurned entirely. In some of the 
earlier experiments some of the old females still attracted males, 
but on these occasions no younger rivals were present. 

While the majority of the males flew direct to the cage from 
Which they were recorded, several flew to various cages, testing 
out, as it were, the qualities of the inmates before alighting. 
If an adherent of the theory of chemotropism still thinks that 
the males are drawn to the females as iron filings are drawn to 
a magnet, let him weigh and consider some instances which I 
observed in detail. 


166 Trans. Acad. Sct. of St. Louts 


At 10:50, male No. 18 flew to cages 5, 3, 2 respectively, and 
then flew away. After a few minutes he returned and flut- 
tered again, this time stopping at cages 2, 5, 4, 2, and then a 
second time flew away; returning a third time he flew to cage 
2 and soon settled down to remain there. 

At 11:30 p. m., male No. 33 flew to the roof and fluttered 
for several minutes each at cages 4, 5 and 6, and then flew 
away; returning he examined cage 4 again and soon settled 
down to remain there. 

At midnight eecropia No. 54 appeared and fluttered about 
cage 6, then 5 and flew away; for some minutes he fluttered 
about neighboring roofs-and then came back as if following 
a new trail and alighted on cage 2 where he remained. 

At 12:50 a. m., male No. 303 examined cages 6, 5, 4 and 3, and 
finally chose 4. 

Between 1:00 and 1:05 three males came but flew to the 
brick wall, to a cranny under the third floor guttering, where 
they behaved as though they were looking for something, and 
then flew away. Closer examination revealed that the breeze blew 
from the cages toward the wall where the air was caught in this 
pocket or nook under the guttering. The males probably con- 
gregated where they found the odor, although they were de- 
ceived as to the location of the females. 

At 1:20 male No. 52 fluttered about cage 5, then flew away; 
returning presently he went to the same cage again and alighted 
there. 

At 3:22 a wild male fluttered for a long time about cage 2 

and finally settled on cage 1; a few minutes later another sim- 

ilarly examined cage 1 and eventually rested permanently on 
2 


eage 
Experiments to Test Reaction to Light. 


We have seen in the previous experiments testing the percep- 
tion of odor that reaction’ to odor stimulus occurs only when 
wind is present to convey it. These experiments have shown 
also that when moths have been aroused to activity by odor of 
the opposite sex, they react usually not to the individuals of 
the opposite sex directly, but fly to the light, even though they 
must pass their mates to go there. . 


Experiments in Rhythmetic Periodicity 167 


The following experiments will show that odors are not al- 
ways necessary to induce reaction to light; that under certain 
conditions of light the moths will react to it. 

The tests were made to see to what degree the recurring 
rhythmic periods can be changed. In Samia cecropia, the period 
has become fixed (with certain exceptions) at the hour of dawn, 
or between 3:30 and 4:30 at this time of year. In so far as 
light conditions are concerned, this period covers all the degrees 
from blackest night just preceding dawn to the light of day 
just before sunrise. The idea in this work was to create at 
various hours during the twenty-four a condition of diffused 
light in as close imitation as possible to that which caused their 
reaction at dawn. For a long time preceding these imitation 
dawns, of course, the moths were kept in darkness, to make more 
realistic these make-believe dawns at various times of day. 

The statement is made by Reamur** that ‘‘most of the night- 
flying moths which are at liberty in the country fly only at 
night or on the approach of night. Some, moreover, of the 
same class when kept enclosed in boxes or cages show the time 
when their inclination leads them to flight. During the day 
they are quiet in their prisons, passing hours, often days, with- 
out Moving, in the same place. But when night had come, even 
before the sun is ready to set, they move their wings and are 
ready to fly as much as their box will permit.”’ 

Without having access to Reaumur’s original publication, 
one does not know to what species he refers; however, my wor 
thus far indicates that night-flying moths, at least those herein 
referred to, do not fly at all hours of the night, but the state- 
ment that when they are enclosed in dark boxes they “‘show 
the time when their inclination leads them to flight,’’ and ‘‘even 
before the sun is ready to set they move their wings and “ec 
ready to fly’’ cannot be accepted without further observation. 
The following experiments will show whether in a really dark 
compartment the moths become active with the recurring period 
of their normal activity. They will also show if these periods 
of activity can be changed by artificial conditions. 

During the early morning period of activity, seven male 
cecropias had flown into the laboratory. As very often hap- 
Pened when they flew in from the west, we found them at rest, 


cas 
**Bouvier, Psychic Life of Insects. 


168 Trans. Acad. Sci. of St. Lowis 


not on the cages of the females, but on the windows facing the 
east where the first rays of light penetrated. These wild moths 
were placed in a wire cage, but when handled they became very 
active and beat their wings against the mesh so harshly that 
for their safety they were transferred to the big glass box. 
This box was darkened with several layers of blankets on three 
sides, top and bottom, but all of the moths continued their 
activity at the open end. After five minutes, I covered this 
end and opened the opposite end; within two minutes all seven 
of the males had fluttered to the newly lighted end. After three 
minutes, this end was darkened and the first end again uncov- 
ered ; almost immediately six of the seven flew back to the light 
end and continued their activity. While they were still active 
during a period of five minutes, I suddenly threw off the cover, 
permitting the light (the ordinary diffused light of a room on 
a clear day) to freely enter the box from four sides and top. 
I imagine their interpretation of this sudden flood of light was 
that daylight had come and it was time to rest, while the previ- 
ous condition, dim light from only one direction and elsewhere 
darkness, had seemed to them dawn, for almost immediately all 
of the moths quieted down and rested calmly. The actions of 
these cecropias under these experimental conditions look at first 
very much like a case of pure phototropism. This simple experi- 
ment shows that they are sensitive to differences in degree of 
light (differential sensitivity), but whether the creatures react to 
certain light waves in a fashion entirely mechanical, I think the 
work as a whole will disprove. 

But to resume the experiment, the moths were still exposed 
to the full light of the room, and all were quiet. So they re- 
mained for half an hour when two of them resumed activity, 
fluttering toward the light, despite the fact that there had been 
no disturbance or change in conditions that I could perceive. 
Then I covered the box entirely excepting a small peep-hole 
through which I could see that it took these two moths just two 
minutes to subside into quietude under these new conditions. 
After another half-hour the cage was again completely uncov- 
ered, but this change called forth no response. Whether this 
indifference was due to their fatigue, or whether strong light 
was as much an inducement to sleep as profound darkness, I 
cannot say. 


Experiments in Rhythmetic Periodicity 169 


Exp. 14. The seven moths mentioned above plus three more 
wild ones were allowed to rest until 5:30 p. m. the next day ; 
the box was carefully covered to exclude the light. In the late 
afternoon, 5:30 p. m., the daylight was supplemented by a 50- 
watt electric light about twelve feet from the box. After hav- 
ing gently placed all the moths at the dark end of the box, the 
curtain was lifted at the end nearest the light. In three min- 
utes, three males had made their way to the lighted end, and 
after ten minutes I counted seven there. This movemnt was 
certainly due to the difference of light and not to the period of 
day, for this was not their normal time of activity and the con- 
trols in other cages did not show any activity at that hour. Of 
course the controls were exposed to the light of the room all 

ay. 

During the forty minutes when the moths were subjected to 
the light from one end of the box only these seven responded 
to the lure of the light, so at 6:10 the moths were all quietly 
Placed at that end of the box and covered, and the blankets 
lifted at the opposite end, which was not so brightly lighted 
since it did not directly face the electric light. During the first 
ten minutes, three males fluttered to the lighted end, and after 
twenty-five minutes, eight were there. These did not flutter so 
wildly as they had done in the first part of the experiment, 
but one cannot expect intense activity indefinitely. But their 
Sensitiveness to the light was unquestionably demonstrated first 
by their going to the lighter end of the cage, and second by 
crowding into the lightest corner of that end as they settled to 
rest. Some critics might say that a part of this activity may 
be attributed to imitation; that a few of the moths are super- 
sensitive to the rays of light and become active on slight stimu- 
lation, and the others follow by imitation or simply by being 
disturbed. This is by no means the first experiment in which 
we have found that a small proportion of the moths remained 
persistently quiet while their brothers all about them became 
active; hence we have reason to believe that each individual 
reacts when and only when he himself is physiologically or 
psychologically ready. : 

Exp. 15. The above was of course a test of the reaction of 
the moths to the dim light; now we shall see if they react like- 
wise to bright light. If the dim lights and shadows of evening 


170 Trans. Acad. Sct. of St. Louis 


and early dawn lead the males to activity in the open, natural 
environment, and if the bright light of day induces them to 
rest or perhaps sleep, as it does the owl or bat, one would expect 
the same results in laboratory tests. 

With this question in mind, at 7:30 p. m., a 75-watt electric 
lamp with a reflector behind it, was placed flush against one 
end of the glass box, while the moths were all at the other end. 
Almost immediately one moth flew into the light until it was 
stopped by the glass. This particular male was, it seemed, 
supersensitive to light, for he was without fail, the first one to 
react in every light experiment; he was easily to be distin- 
guished from his companions by black pubescence on his head. 
After ten minutes, two more responded, somewhat languidly, 
and then no more came. These three were marked and replaced 
at the dark end with their companions. After five minutes two 
of these were at the light again, and after two minutes more 
the other marked moth joined them. In a previous experiment, 
eight out of ten responded to dim light; here only three out of 
ten responded to bright light. This shows clearly that the ma- 
jority react to dim light, while only a small proportion are at- 
tuned to the high intensities. One wonders what were the ec- 
eentricities or the special endowments of the one individual 
with the black pubescence that enabled it or drove it always 
to respond first to the lure of the light, both dim and intense, 
while many of his brothers rested. 

One might suspect that fatigue came in about the time this 
test with the bright light was begun, and that for this reason 
few responded. To test this point, I repeated the first part. 
after having kept the moths in the box in darknesss for an hour. 
I then placed the moths in the north end, and uncovered the 
south end of the box next to the small lamp twelve feet away. 
Within ten minutes, eight again out of the ten responded to the 
stimulus by flying to this end. Then I repeated the bright light 
test, placing the 75-watt lamp against the end of the box after 
shifting all of the moths to the other end; it took just twenty- 
five minutes to bring one moth to the light, and no others fol- 
lowed. Once more I tried the dim light. Within two minutes, 
two of the moths reacted, and after ten minutes six were there 
and the other two registered their response by flapping a 


Experiments in Rhythmetic Periodicity 171 


wings. By this time I was convinced that these happenings 
were to be accepted as action and not accident. 

Of course the dim light was some distance away and the 
bright light flush with the side of the box. Now the questions 
come to mind, whether the insects were far-sighted or near- 
sighted, and what difference would their vision make in their 
reactions. Unfortunately, no experiments could be made at that 
time to learn their response to a bright light at a distance. 

These laboratory experiments on the reactions to light bring 
us again to the puzzling question which probably will never be 
answered. In the open these males fly past street lamps, house 
lights and numberless automobile lights in order to reach my 
laboratory to meet the females there. Then when in that lab- 
oratory, they are so influenced by light rays that they leave the 
female nearby and passionately beat their wings on the win- 
dow toward the light until they die of exhaustion. 

Of course this experiment shows also the futility of trying to 
account for this behavior by phototropism. If the reactions 
were actually phototropic, then all of one lot should react, or 
not react, but all in the same way while under the same in- 
fluence. Loeb in citing his instances for animals of various 
orders says they did or did not react thus and so. He does not 
take into account exceptions, individuals that did not go with 
the crowd, and we assume that none existed. But here in this 
work we do find exceptions, and these exceptions should not be 
overlooked. A chain is as strong as its weakest link, and the 
theory is weakened just in proportion to the number of ex- 
ceptions. 

Exp. 16. May 21. The purpose of this experiment was to 
test on a larger scale the reactions of cecropia males to light 
of weak as well as strong intensity. Seventy-eight males came 
in at dawn that day; these were all placed in the large glass 
box and kept tightly covered with blankets. 

At 3:15 p. m., the cover was lifted at one end. The light 
at that time was the ordinary light of a room with two east 
windows. Almost immediately some of the moths began to vi- 
brate their wings, and in five minutes about three-fourths of 
them registered some response. Some waved the Wings, others 
fluttered to the light end, and many crowded and beat ease 
Selves against the glass in great commotion. The vibration o 


172 Trans. Acad. Sci. of St. Louis 


so Many wings created a loud humming noise. Many of the 
males kept their antenne in excited motion much of the time, 
and in one case an individual crowded near to the glass and 
pulsated his abdomen in unison with his wings. 

Seven minutes of this activity gave all the evidence that we 
needed, so I darkened the box again; almost immediately the 
hum subsided, and quiet reigned. This condition continued for 
thirteen minutes. Then the cover was lifted at the opposite 
end and the strong light, the 75-watt lamp with aluminum re- 
flector, was placed against the outside of the glass. It was three 
minutes before any of the 78 moths showed signs of response, 
and then only two slowly vibrated their wings. After seven 
minutes, eight were waving the wings; three of these came to 
the light. After being subjected to this dazzling light for ten 
minutes, five were flying against the glass part of the time, 
and part of the time they flew back into the corners away from 
the light. One more male occasionally moved a wing. Thus 
of the 78 moths, only 6 made response to intense light, and the 
majority of these responses seemed half-hearted or confused, 
and in a few minutes, even while the light was upon them, these 
settled down to quietude. After a quarter of an hour it was 
evident that the show was all over, so the cage was again dark- 
ened. An hour later it was opened again at one end to see if a 
larger number would now respond to a mild light (that of an 
east room at 5:00 p. m.). Immediately when the curtain was 
lifted, three moths broke into fluttering, and in three minutes 
three more were beating against the glass at the light end. After 
the cover had been up ten minutes, twenty moths were doing 
various antics, as before. It was growing darker in the room 
now, and rather than turn on the electric light (since this was 
to be an experiment with subdued natural light), I admitted 
more light to the box by lifting the curtain on one side in addi- 
tion to the one end that was already exposed. In five minutes 
more than half of the inmates of the cage had joined in the 
excitement, but after eighteen minutes many of those which 
were first active began to slow down and a few became quiet. 
Here again we find much greater response to diffused light of 
low intensity than to intense light. To the moths, et 
the opposite extremes in the intensity of light mean eee 
ingly opposite behavior; brilliant sunlight or its counterpart 


Experiments in Rhythmetic Periodicity 173 


correlated with sleep or rest, while dim light suggests to them 
activity and mating. 

In other cages nearby while this work was in progress were 
moths of both sexes bred from cocoons in the laboratory, and 
other native males that had been attracted by our females, but 
none of these showed any signs of activity at this time of day. 
They were exposed all the time to the normal changes of night 
and day, and their program was not disrupted by artificial imi- 
tations of darkness, daylight and dawn. Hence it appears that 
the activity of these creatures is regulated by the changing in- 
tensities of light and not, as has been thought by many investi- 
gators, by the clock. Of course it was not the normal time for 
activity of those in the glass box, any more than it was for the 
others in the room, but they were easily fooled into activity by 
fake dawns, at any time of day we wished to stage them, so long 
as we did not work them to the point of fatigue. The fact that 
their periods of rhythmic response is altered by light conditions 
shows that this habit is not so deeply ingrained in their psychol- 
ogy (or is it their physiology, or is it both?), else it could not 
be so readily changed. The fact that cynthia does not so readily 
change its periods under similar conditions makes one suspect 
that cynthia is phylogenetically older, since her habits are more 
deeply ingrained. 

Exp. 17. June 2,1:30 p.m. Temperature, 66° F. If any- 
one should offer the criticism that my experiments were made 
early in the day, too soon after the moths had come in from 
their flight at dawn and their reactions were merely a result of 
the momentum acquired in that flight, or that some of them 
were made too late in the evening, at a time too near to the ap- 
proach of their next flight at dawn, Exp. 17, which was made 
at 1:30 p. m., a time half-way between the two, should set them 
at ease. : 

Thirty-five males that had flown in at dawn were kept in the 
darkened glass box until 1:30, when they were all gently placed 
at the north end of the box and the curtain was lifted from the 
south end. They were so utterly lethargic that they seemed 
fast asleep. Since, as we know, insects do indulge in sleep, 
why should not this time of day be most suitable for them? 

Within six minutes, however, six males were fluttering at 
the light end of the box, and during the next few minutes this 


174 Trans. Acad. Sci. of St. Louis 


number increased to 17. At 1:50, after the light had been 
played upon them for twenty minutes, 25 moths were counted 
at the light side. When so many were moving together, it was 
hard to tell just how long each moth continued its activity, but 
in this experiment ten minutes seem to be the limit for any 
one individual. Thus we see 71 per cent of this population 
reacting to mild light rays at a time of day midway between 
the two normal periods of darkness. 

Exp. 18. This is a continuation of Exp. 17, but made with a 
purpose of getting additional data on the reactions of moths to 
light of greater intensity. 

These same moths, 35 in number, were placed at the south 
end of the cage and kept in darknesss for 25 minutes. Then 
the curtain was lifted and a 40-watt lamp was pressed against 
the glass at the north end. Now the intensity of the light from 
this lamp was intermediate between the two extremes previously 
used, a 75-watt mazda lamp and the subdued light of the room. 
This being the ease, we should expect the number that respond 
to be intermediate between the numbers that reacted to the two 
extremes. 

During the first five minutes, four moths flew to the lighted 
end, but after a few seconds three of them retired again to the 
dark side and one alone continued its activity. Ten minutes 
after the curtain was lifted, 8 were fluttering at the light; their 
movements gradually became less intense, while slowly a few 
others came, until at the end of 35 minutes, 12 were at rest at 
the light end of the cage. This is 33 per cent of the total, which 
responded to the light of a 40-watt lamp, while less than 8 per 
cent reacted to the strong light of a 75-watt lamp, and 71 per 
cent responded to the diffused or dim light of the room. How 
gratifying it is to find our anticipations fully realized; the pro- 
portion of moths responding to the light of intermediate m- 
tensity was just about midway between the proportion respond- 
ing to either extreme of light! It is also evident that the time 
required to induce the reaction is increased with the intense 
direct light. In 20 minutes we got 25 males to fly at the stim- 
ulus of diffused daylight, whereas in the direct light of a 40- 
watt lamp it required 35 minutes to influence half that number. 
But best of all in this experiment, we prove that the hour of 
the day is no stimulus to action, but light conditions are, Te 


Experiments in Rhythmetic Periodicity 175 


gardless of whether the experiments are carried on morning, 
noon or night. 

Exp. 19. This test was made to test the reaction of the female 
cecropias to light. In the literature one finds little or no men- 
tion of the activities of females, excepting their mating or egg- 
laying. People are satisfied with the assumption that the female 
merely sits and awaits the arrival of the male; hence it is start- 
ling as it is interesting to find, experimentally, that she some- 
times plays an active part in the meeting of the sexes. 

Thirty-two females, all from one lot of cocoons and all three 
days old, were placed in the dark box at 8 a. m. After 614 
hours the cover was lifted at one end and the six which chanced 
to be near that end were gently placed in the dark corner. 
Within five minutes seven of them had come to the light end; 
for a time two fluttered about excitedly, more actively than one 
would expect of a heavily laden female, but they soon subsided. 
Fifty minutes more were allowed, but no more responded to 
this stimulus. Then the light was changed to the 40-watt lamp 
with a reflector on the back, pressed against the end of the box. 
Only two more responded to this dazzling illumination by mov- 
ing ten inches toward it; a half hour brought no further move- 
ments. Lastly, the entire cover was removed, admitting dif- 
fused light of the room from all sides, but not a moth stirred. 

After a half-hour’s rest I placed a cage containing seven two- 
day-old males in the box, at the end nearest the window, and 
fanned the air into circulation. Within ten minutes eight of 
the females had flown to this end of the box and three of them, 
heretofore sluggish or immovable, were clinging to the cage des- 
perately beating their wings against the wire mesh. After 
fifteen minutes eleven females were around the cage of males, 
some of them in wild excitement. 

These tests show, then, that some females at least (7 out of 
32 in this ease) mildly register the perception of light per se, 
but when the stimulant of sex odor plus movement of the air 
is added, a larger number (11 out of 32) show intense excite- 
ment and aggressive action. This experiment clearly shows, too, 
that not all of the females are similarly endowed for the percep- 
tion of light or odor waves. 

To conclude, then, with an answer to the query in our open- 
ing paragraph, we find that some females at least are endowed 


176 Trans. Acad. Sci. of St. Louis 


with sensitiveness and react to certain conditions of light and 
odor; moreover, some display much emotion, and some make 
strenuous advances in courtship. 


Summary 


We find that the phenomenon of the nocturnal periodicity of 
the males is not so deeply ingrained in the psychology of the 
cecropia moth that it cannot be changed with changes in the 
condition of light and darkness. It seems they respond to re- 
recurring periods of light of certain intensity, whether these pe- 
riods occur once or half a dozen times in the twenty-four hours. 
If the measured periods were deeply ingrained in their be- 
ings, whether physiological or psychological, they would react 
only when the cycle (hour) recurred, regardless of whether 
they were in a darkened box or in the brightest sunshine. As 
a matter of fact, they do not become active under either of these 
two extremes, but the optimum activity is reached under con- 
ditions of diffused daylight, which to them is probably similar 
to the light of very early dawn. If this condition is created at 
almost any time, a good percentage of responses may be 
expected. 

In regard to the females, the experiments show that they re- 
spond mildly to proper light conditions, and more actively when 
the odor of males is added. The female is not wholly devoid of 
sex perception; she has the ability to perceive his odor and has 
the power to reach him when he is in the path of light. More- 
over, she displays enough emotion to proclaim to the world that 
she, too, is a party in the courtship. 

The results of this series of experiments on light reactions 
show for the males at least positive response to the stimulus of 
diffused daylight, negative response to direct electric light of 
high intensity, and a response half-way between the two for an 
electric light of medium intensity.* This, of course, is what one 
would expect in a moth whose activities are influenced by day- 

ennedy (Ann. Ent. Soc. Amer. 20: 87, 1927) finds that aren) 


Pon — are so sensitive to light that they are eg eig e 
talepsy in strong light by overstimulation. He 


lf mile away, ignorin. 
stone flies siranted to a 75-watt light ha oS eae 


candle power gas mantle lantern on a creek bank. He also 
hanging on = Bolo motionless, with an electric light on. = ssn 
went out and a single candle was lighted; some two d en tha 


been hanging sattonGaas then became fully active. 


Experiments in Rhythmetic Periodicity 177 


light intensities of the period of early dawn, when their normal 
flight takes place. In nature, bright light means enemies and 
danger if they are in flight; therefore daylight means motion- 
less rest and sleep. The reactions which the moths displayed in 
our tests would be very fitting in the wilds of nature. 


Activity in a Dark Room. 

If the rhythmic periodicity is something innate and is not 
influenced by surroundings, then we shall find in these moths 
the activity returning with the recurring hour each night, re- 
gardlesss of external conditions. If we shut out the stimulus 
of light, by keeping the room entirely dark, we should expect 
to find that the flight has occurred at the regular time, and in 
the morning the moths will be scattered about the room. To 
this end the following experiments were done: 

Exp. Di6. June 4, 9 p. m. Fifty-two moths, comprising 
thirteen each of male eynthias, female eynthias, male cecropias 
and female cecropias, were placed on the south wall and the 
room darkened. The next morning I found 36 moths just where 
I had left them, and 16 were crowded around the door; this 
door was closed, but did not fit tightly at the bottom, and where 
a small pencil of light penetrated, the only streak of light in 
the room, they had congregated. This simple test shows that 
the moths do not act merely because it is their appointed hour to 
act, but without the stimulus of a precise condition of diffused 
light they pass the hour of dawn unmoved. It also shows that 
some supersensitive individuals can sense a meager trace of 
light and respond to it. 

Exp. D17. May 5, 11 p.m. We know that polyphemus are 
abroad in quest of mates during the entire night, and that their 
activity is influenced by moonlight. In this experiment we want 
to see if they can be induced to inhibit their activity during 
the night if they are placed in a totally — If 
they fail to move about when the luminous rays are eliminated, 
then we know that the rays influence or perhaps induce the 
Movement. If they react in spite of the absence of any varia- 
tion in the light, then we shall feel that their reactions are in- 
nately bound up with the physiology of their beings and reap- 
pear at recurring periods, regardless of any outside stimuli; in 
other words, their rhythmic periodicity recurring once In each 


178 Trans. Acad. Sct. of St. Louis 


twenty-four hour period, is as deeply rooted physiologically as 
the rhythmic periodicity of the mammalian heart-beat. 

The room was darkened to the best of my ability; even the 
troublesome crack under the door was plugged. Twenty-eight 
polyphemus of both sexes were used; some of these were 2 to 5 
days old, and had been used in previous experiments and had 
reacted to light stimuli, and some were young moths, 1%4 day or 
less, which had never had such an experience. All of the moths 
were placed on a blanket on the south wall and left undisturbed 
for the night. 

At 7:30 next morning all of the moths were in their places; 
a few of the energetic ones had crept up the wall a few inches, 
but among the older ones not one had moved at all. A second 
examination at 7:45 p. m. showed that there had been no flight 
during the day. Some had crept up the wall a few inches 
more, and a few had fallen to the floor, but lay just beneath the 
blanket. Thus it was evident that they had not at any time in 
the twenty-four hour period been overtaken by the wild 
paroxysms of excitement and flight that they display out under 
the stars every night, or they would have been scattered all over 
the room. Even though the 14 older ones had during the last 
three or four days flown repeatedly to the window in other 
experiments, not one of them now so much as started toward 
the same window, either by day or night, when the light was 
excluded. At 9 p. m. there had been no movement, so the ex- 
periment was changed. 

At the opposite (north) end of the room was a closet with a 
drop electric light. Here a 60-watt lamp was turned on and 
the door almost closed, so that only a pencil of light one-fourth 
inch wide and as high as the door shone out. Between 9 p. m. 
and midnight, 7 moths came to this light (8 males and 4 fe- 
males), and the next morning 6 more were there. These 18 in- 
eluded both young and old of both sexes. When I examined 
those which did not respond, I found 10 dead in their tracks 
and 5 aged females; hence there is evident reason why more 
did not react. 

Thus this simple test shows that these polyphemus do not 
act merely with the recurrence of a certain interval, but they 
must have light rays (of a low intensity), of course, to stim- 
ulate or enable them to go through the usual activity. This 


Experiments in Rhythmetic Periodicity 179 


leads to the conclusion that their movements are caused by ex- 
ternal stimuli and not by something within. 


Relation of the Movement of Male Cecropia and Polyphemus 
to Moonlight 


While waiting through the night hours for the moths to come 
in, it often seemed to me that on moonlit nights an unusual 
number of moths were abroad. To test this point, I remained on 
watch all night, or all but an hour, for seven nights, and kept 
records of the moths appearing on the roof, together with the 
weather and moon-light conditions at the various times. The 
resulting data are too bulky to be presented here, but the fol- 
lowing table gives a summary of the seven nights’ observations: 


No Bright Half Dense 
moonlight moonlight moonlight fog Total 
Bred cecropias.......... 5 $14 35. 1 eS 
Wild cecropias.............. 0.2% 4 4-2 8 7 
Bred polyphemus: 3 "4, 3, 74 <1, © 0 
Wild polyphemus..2 4 0,295 0,4 0 46 
0 


Total number flights 8 86 19 113 
Immediately the figures show that my impressions were not 
in error; the average number in flight on the bright nights 
was more than twice the number on dark nights. The times 
when the moonlight was subdued or when light and darkness 
fitfully alternated brought forth an intermediate number of 
moths. It is easy to imagine that they awoke and started on 
their journey during an interval of brightness, and the tem- 
porary darkness did not arrest them. On one night the moon 
was completely obscured by a dense fog, and all night long I 
waited in vain, for not a single moth of any description came in. 
I cannot believe that the severity of the weather, the difficulty 
of flying in the moist atmosphere, could have prevented their 
flight, since I have seen them come in in large numbers through 
a drenching rain. Rather, this instance may be explained by 
the lack of wind. Our previous evidence indicates that wind is 
the chief factor in inducing the flight of moths in the open, 
and fog indicates a total absence of wind; hence the moths could 


180 Trans. Acad. Sci. of St. Louis 


not orient themselves to the cages on our roof. Of course it is 
possible that the faint light might have aroused them to action, 
and that they were flying aimlessly hither and thither, without 
any trail to follow, and we could not know this. Thus it is 
evident beyond doubt that moonlight is a potent factor in the 
activity of these creatures, arousing them to action in a consid- 
erable number of cases at all hours between 11 p. m. and the 
hour of dawn or 3:30. 

The species also vary in their response to moonlight. During 
these seven nights the wild cecropias came in at dawn in hordes, 
but only 7 responded to the moonlight at other hours, and none 
at all came in early without moonlight. The cecropias which 
had emerged from cocoons kept in the laboratory showed a far 
greater tendency to fly by night, not waiting for dawn as had 
the wild ones. Although the wild ones in the region far out- 
numbered the bred ones which we had liberated, yet 48 of the 
bred ones came in early as contrasted with only 7 of the wild 
ones. 

The polyphemus shows a much stronger tendency to fly at all 
hours of the night instead of confining their activity to the hour 
of dawn. Although they are not nearly so numerous as are 
the cecropias in this region, they came during the moonlight 
(table above) in equal numbers. The figures above indicate that 
polyphemus is more susceptible to moonlight. 


Thermotropism. 


On May 16 at 8 p. m., I had 20 male cecropias and 3 male 
polyphemus in the glass box. The temperature was low (54), 
and they did not respond readily to my light experiments, for 
only 4 moved. Therefore I placed an electric heater in the box 
and watched the thermometer go from 54 to 60. This brought 
an additional 6 to the light side. When the heater was turned 
off, they rested. An hour later the heat was again turned on 
and the thermometer reached 64. One by one the moths which 
were already at the light side of the box resumed their agita- 
tion, and were joined by ten others which had remained indif- 
ferent to all stimuli at a lower temperature, until soon all m 
the box were active. Now this temperature is not high for these 
species, for in Nature, during the period of their adult life the 
temperature is often above 80. The reaction is to be explained 


Experiments in Rhythmetic Periodicity 181 


aS one of differential sensitivity; the change from 54 to 64 
aroused them to a response to the light. The heater was turned 
off; a half-hour later the thermometer still registered 64. The 
light end of the glass box was gently darkened, and the cover 
lifted at the opposite end admitting the light. Within four 
minutes 10 ceeropias and 2 polyphemus (more than half of the 
lot) had traveled to the light side. 


On May 4 the temperature of the room was 59; this was lower 
than that of the three previous days, which had been 71, 66 
and 68. The moths in their cages were very sluggish ; none would 
move about unless prodded. These were 9 in number, 2 male 
and 3 female polyphemus and 4 male ececropias. At 9 p. m. I 
placed an electric heater so that a stream of heat waves would 
pass through all of the cages. Almost immediately they began 
to ‘‘ecome to life,’’ and soon all were fluttering about the tops 
of their cages. There was only one exception; that was a fe- 
male polyphemus only six hours old. When at last the ther- 
mometer among the cages registered 80, she also became active, 
but moved downward. Thus it is apparent that a sudden rise 
in temperature is conducive to the activity of these creatures, 
whereas at a lower temperature they remain motionless. The 
only thing that puzzles me in this matter is the question of just 
how this factor would function in the lives of the wild moths. 
All marked rises in temperature are very sure to occur during 
the day, at which time they are never abroad; hence it seems 
to me there would always be a conflict of reactions, whether 
they should respond to sunlight by sleeping or respond to rising 
temperature by waking. 


Normal Activity. 


I have shown in the electric fan experiments how the occu- 
pants of a cage in close proximity to another cage wherein the 
moths were in a high state of activity were not susceptible to 
suggestion, and remained uninfluenced by the activity of their 
neighbors. In other words, despite the fact that the males could 
See, smell and hear the activity of others near them, they offered 
no imitation. The moths became active only when, in the lan- 
guage of the street, ‘‘they got good and ready.”’ Of course that 
Means when their physiology became attuned to something or 


182 Trans. Acad. Scr. of St. Louis 


other. The following data, gathered at odd times among other 
tests, substantiate the electric fan experiments. 

On the evening of May 5 the temperature was from 58 to 
64 F. There were four males (polyphemus) in separate cages 
and 5 females in another cage side by side on the table. No 
contrivances for artificial wind, heating or lighting were used, 
excepting the ordinary electric lighting which illuminated the 
whole room. I merely watched to see if any of them seemed 
to be influenced by the activity of one, or to imitate it. Now 
when the males become active in these secreen-wire cages, the 
vibration of the wings against the mesh creates a humming 
which is almost musical, and loud enough to be heard from the 
floor below; the motion of their wings can certainly be seen by 
their near neighbors, it is probable that the motion of the air 
thus caused could be felt for a short distance, and lastly, the 
beating of the wings must stir up and disseminate the odor from 
their bodies which the others should be able to perceive. In 
short, it seems reasonable to think that one of these moths 
might become aware of his neighbor’s activity through sound, 
sight, odor or touch. 


Male 5, age 2 days, became active at 8:00 p. 
Male 4, age 2 days, became active at 9:10 p. 
Male 2, age 5 days, became active at 11:05 p. 
Male 3, age 5 days, became active at 11:30 p. 


BREE 


Each of these remained active for five to ten minutes, and 
then stopped. Thus each conducted his own affairs without 
the slightest consideration of the dictum ‘‘everybody’s doing it.”’ 
The five females in an adjacent cage showed no response what- 
ever. : 

One sees much variation in the duration and strength of the 
activity of the individuals in their cages. The activity of groups 
is in great measure regulated by weather conditions. Cool 
periods, especially in the early months, cause long periods of 
lethargy, while warm days call forth periods of activity. It 1s 
not surprising that the females are much less active than the 
males, in both frequency and strength of movement. For two 
weeks I made careful note of two polyphemus females, and found 
them almost never moving from the very spot where they were 
placed on the wires, where they clung with great tenacity. Dur- 


Experiments in Rhythmetic Periodicity 183 


ing a period of two weeks there was never a voluntary movement. 
I think this unusual lethargy may be attributed to the low 
temperature of that time. The minimum for the fourteen days 
varied from 38 to 64 F. When a female was handled or prodded, 
it slowly opened and closed the wings, and lapsed again into 
repose. 

One evening from 10:30 until midnight I permitted a very 
lively male to flutter about the room, and soon he turned his 
attention to the ten cages containing 18 females. The position 
of each of the moths was marked with paint on the outside of 
the cage. As his flutterings among them became more and more 
wild, I expected some sort of response, at least a movement of 
the wings, but not one of them stirred during the hour and a 
half, and the marks at the end of the time showed that no un- 
noticed movement had occurred. The temperature was 55. This 
temperature did not cool the ardor of the energetic male, but 
the females were indifferent in his presence when the tempera- 
ture was below optimum. On other similar occasions, when this 
factor was favorable, the females have displayed emotion. On 
May 18, when the temperature was 75, one female which had 
just concluded mating fluttered at intervals for six hours. 

Rythmic Periodicity in Platysamia cynthia. 

Cynthias are sluggish in cages and are seldom seen to move. 
They are good fliers, however, and in moving them from cage to 
cage one must be careful, for they are quick to escape, and oor 
out of the window they fly high, even when the sun is bright. 
But they do not like the sun, for they always come to rest in 
some shady spot. The females often remain motionless for days 
at a time, but if one is liberated in the open it flies high and 
more lightly and swiftly than cecropia. : 

We have seen in the cecropia that light of the optimum 
intensity at any time of day regulates the activity of the males 
and to a lesser degree that of the females. In nature, the normal 
time for the flight of cecropias is just before and during the 
hour of dawn; it seems that some of the males can perceive the 
approaching dawn and fly before dawn overtakes them. Under 
very exceptional circumstances, cecropias fly at other hours dur- 
ing the night, as noted in the early experiments on homing. The 
time of flight of cynthias is several hours before midnight. They 
present a distracting list of variations in their flight ; sometimes 


184 Trans. Acad. Sci. of St. Louis 


male cynthias fly in at dawn just as cecropias do, and others 
even when liberated near the windows where the females are, 
wait until dawn to come in; on moonlight nights they respond 
to some extent to the light of the moon, and they never fly by 
day, although Weed* states that on cloudy days they fly during 
the day. All this, though confusing, indicates that the flight 
of cynthias is regulated by light conditions and that in the eve- 
ning at certain periods and at dawn the light intensities are 
such as to cause response. This, of course, means that cynthia 
finds more periods out of the twenty-four hours when light con- 
ditions are optimum for its activity, whereas cecropia under 
natural outdoor conditions reacts during a very limited period 
of one hour during dawn. Since cecropia with its usual limited 
period for response reacts to light conditions (experimental) at 
any time during the twenty-four hours, what must we expect 
under experimental conditions for cynthia, which has been found 
active at various times of evening, dawn, night and even cloudy 
days? In the face of these difficulties, experiments were under- 
taken to see what their reaction would be to definite light con- 
ditions. Since the glass box was then in use for the cecropia 
experiments, the following tests were made in the third-floor 
room with two east windows. The following year two box ex- 
periments were made, and these are given first. 


Exp. 20. June 23, 1924. At 7p. m., five cynthia moths (3 
females and 2 males) were placed in the glass box and this was 
completely darkened and kept so for thirty hours. At 1 p. m. 
the next day, the cover at one end was lifted, but none flew to 
the light then. When I examined the box at 6:30, none had 
gone to the light, but at 7:30, all had flown to the light end of 
the box. This indicates, of course, that they are not influenced 
to activity by conditions of light or darkness, but that their 
activity oceurs periodically. 

Exp. 21. June 6, 1924. At 7 a. m., twelve eynthias of both 
sexes were placed in the darkened glass box, with the cover 
lifted at the north end. They were given an opportunity durmg 
the entire day to move to the light, but up to 7 o’clock all re- 
mained precisely where they had been placed. Between 7:15 
and 8:05, all but one flew to the light. At this time six more of 
both sexes were added at the light end of the box and the cover 


* Butterflies Worth Knowing, p. 14, 1917. 


Experiments in Rhythmetic Periodicity 185 


dropped, and the light was admitted now from the opposite end. 
There were now 18 moths in the box. By 8:15, two were at the 
light, at 8:45, six and by 10 p. m., twelve were at the light end. 
During the night the others followed, so by day-break all were 
there. This of course was their normal period of flight. 


All of the 18 were left there, and the lighting was again re- 
versed by dropping the cover and raising it at the opposite end. 
This was done to see if they would travel to the light during the 
day. Up to 6 p. m., only three had moved to the light, but at 
that time the migration seemed to occur, for by 8 o’clock six 
more were there, and at 10:30, sixteen were there and the other 
two were dead, so the result may be considered 100 per cent. At 
11 p. m., the curtain was again dropped over the end where they 
were congregated and lifted at the opposite end. No detailed 
observations could be made during the night, but the next morn- 
ing at 6, all were again at the light end. 

Exp. 22. June 26, 1923. At 8 p. m.,, six eynthias which had 
emerged during the day were at rest on the south wall. Highteen 
males which had successfully made a flight to the roof two 
nights before were placed on the north wall. Then I shaded a 
60-watt lamp which hung in the middle of the room in such a 
way that the six moths were brilliantly lighted, and the wall 
with the 18 males was dimly lighted. This arrangement was 
left from 8 to 10 p. m., but it gave rise to no response in either 
direction, either toward the bright light or to the subdued light. 
Then I reversed the illumination, throwing the six in the dim 
and the eighteen in the strong light. During the next two hours 
there was no response from either group of moths. 

Before retiring, I placed whatever cynthia material I had on 
hand on the south wall, and left the room darkened excepting 
the light from the street which entered a small window with 
the shade half drawn near the north end. There were now 82 
moths, of which 54 were males and 28 females. At 3 a. m., ae 
of them had moved. I was not on hand at sunrise, but a little 
later I found great numbers of the moths at or near the window ; 
on the window and sash were 46 males and one female; on the 
walls near-by were 7 males and 7 females, making a total of 60. 
When a census was taken of those which had made no attempt 
to come to the light, there were 21 females and one male! 

Thus we see that practically all of the males moved to the 


186." Trans. Acad. Sci. of St. Louis 


light, and about one-fourth of the females also. In all prob- 
ability these cynthias did respond to the light of early dawn, 
because in the homing experiments many of them did come in 
with the cecropias at about 4 a.m. In this case, as in the other 
species, it is surprising that the moths did not respond to the 
glare of the automobile headlights flashing intermittently in the 
windows before the hour of 3 when I examined them. 

In the first part of the experiment there was no reaction to 
the intense light, because physiologically they were not attuned 
to become active in those conditions, but later experiments will 
show that even when the hour recurs for their activity, they 
will not react if the stimulus of correct light is lacking. It is 
interesting to note that, when once they are in the light, there 
they remain quietly at rest throughout the day, regardless of 
the fact that the hot sun is curtailing their lives*; they have 
never been observed to make the slightest move to seek a more 
sheltered place. When once in the light they seem to be trapped. 
During these periods they cling tenaceously to their support; 
unless one has the task of pulling them off, one little suspects 
that their feeble-looking tarsi possess so much power. With the 
return of night, they fly wildly about the window pane. 

In this experiment where all of the males and 25 per cent of 
the females went to the light, one would expect all of the females 
to have mated; on the contrary, only one pair mated, even in 
this close proximity. In this species as in the cecropia, the pur- 
pose of the action is to fly to the females, and the stimulus is 
light rays of a certain intensity, but in the excitement of the 
reaction or for some unkown cause, they pass by the females 
even when in close proximity and the vital purpose is defeated. 
Someone may stretch a point to say that the passing by of the 
males when too near to the females may be an adaptation to in- 
sure cross fertilization, since probably all the adults of a limited 
area are from the eggs of one mother. But who, pray tell me, 
would be so bold as to make a case of this speculation? It is 
much more likely that there was no mating at the window be- 
cause there was no motion of the air. 

Exp. 23. June 27, 11:50 p. m. Room dark; only three-quar- 
ters of one window in the northeast corner uncovered ; no wind 

*In the case of an insect that takes no food, the duration of life 
See Rau, Trans. 


is shortened by warmth and lengthened by coolness. 
Acad. Sci., St. Louis, 23:1-78, in 1914. 


Experiments in Rhythmetic Periodicity 187 


in room. Fifty-three males were placed on the south wall, and 
on the floor a few feet in front of them was placed a cage con- 
taining 40 females. The object was to see if they would be 
attracted to the females in preference to the rays of light at 
dawn, despite the fact that the air was motionless, 

Heavy rain and wind prevailed during the night, and at 5 
a. m. when I went to the room I found a cool, gray dawn, with 
less light than usual at that hour, but at the lighted window 
were 48 males; only 5 remained unmoved. All of these had 
passed by the cage of females, but not one had paused in his 
response to the lure of the soft light of dawn. But furthermore, 
I had placed at the window 10 females without a cage, but 
despite the fact that there were here five males to each female 
and in close proximity, there was not a single case of mating 
among them. 

I left them there and could pay no attention to them until 
evening. The sun shone intermittently during the day, and at 
times they were in the hot June sun, but none retreated to 
more comfortable quarters. During the evening, I watched them 
at short intervals to see at what hour their activity would begin. 
Until 8:30, all were quiet, but at 9 o’elock I found about half of 
the males fluttering wildly against the pane, as if they were 
trying to reach the moon, which was by this time shining in 
front of them. It seems that this action was actually influenced 
by the bright moonlight, for only ten minutes later when the 
moon was suddenly hidden by a cloud, all but two of the moths 
as suddenly ceased their activity. All this time the two cages 
of females, one with 50 that were four days old and the other 
with 40 moths 114 days old, were in the room, about ten feet 
away, but not one male showed the least indication of leaving 
the lighted window to pay them the slightest heed. This eter 
tling condition cannot be without significance in determining the 
Senses of these creatures, Lutz,* in referring to the case of 
Moths where the males are supposed to locate the females by 
odor, says: ‘‘that none of the experiments believed to have 
demonstrated that odor is the guiding factor in the case of moths 
have absolutely ruled out sound, and male moths have antennas 
quite as plumose, apparently as well fitted to receive sounds, 
as those of male mosquitoes.’ This statement, of course, pre- 


~ “nsect Sounds, Am. Mus. Nat. Hist. 50:337. 1924. 


188 Trans. Acad. Sci. of St. Louis 


supposes that the sounds must be emitted by the female, if the 
male is equipped for hearing such sounds. Here in two cages 
were 90 females of attractive ages at one end of the room, and 
if they had emitted a sound which the males could hear, surely 
at least one out of the 48 which were at liberty in the same 
room should have responded. 

After the moon had reappeared and the moths had resumed 
their fluttering against the pane, I turned on the 50-watt lamp 
in the middle of the room to find if, while they were in this 
state of excitement, their attention could be directed from the 
moonlit window to the bright light near by. It will be remem- 
bered that in Exp. 22, when the moths were quiet, there was 
no reaction to this type of test. After 30 minutes, 23 of these, 
or about half the number, were flying vigorously about the room. 

At 10 p. m. the room was darkened and all of the males, now 
47 in number, and 10 females were placed on the south wall. 
At 3:25 I awoke, early enough I thought to observe the migra- 
tion, but I was mistaken, for already 43 males were resting on 
the window sash at the northeast corner of the room. Whether 
they had responded to the lure of the moonlight during the 
night, or whether they had been guided by an impulse to move 
at the accustomed hour, I do not know, but at that time the 
moon was low in the west, while the window faced the east. 

At 9 a. m., there was no change in their. positions, so all were 
replaced on the south wall, to see if they would react to the 
lighted window in the same way during the day. They were 
watched at frequent intervals, but not one moved to the window 
during daylight hours. Between 8 and 9 p. m., however, there 
was a general exodus, 40 males and 3 females making their way 
to the window at that time. The moon could not have caused 
the exodus, for it did not rise until 9:30. I have wondered what 
part the flashing headlights of automobiles, as they came out 
the park gate opposite, might have had to do with their action 
after dark. 

At 11:05 the old and decrepit males were eliminated, thus re- 
dueing the number to 27. These were again placed on the dark 
south wall. The next morning, all but 3 were again at the win- 
dow. It had been my intention to take a nap until two o’clock 
and then watch them constantly until dawn, to get the actual 
time of their movement, but the weakness of flesh prevailed, and 


Experiments in Rhythmetic Periodicity 189 


I missed this observation, so this night means but little. In the 
morning I once more placed them on the south wall, to see if 
they would respond to the light of the window during the day. 
This test, with identical surroundings and material, had pre- 
viously given negative results during daylight hours. This time, 
however, there was some reaction, which shows that the moths 
can as they grow older, or through place memory, create new 
periods of activity. Before noon six of the males, almost one- 
fourth of them, had flown to the lighted window. These moths, 
remember, were the identical ones which had declined to do this 
trick for us on previous days, under conditions which were, so 
far as we could see, identical. 

These six were replaced on the wall. At 8:30, I found them 
all fluttering about the room; 9 went to the window during my 
five-minute visit, but I could not remain with them. At 11 p. m., 
25 of the 28 males were on the window. The moon did not ap- 
pear until 9:15. 


N 
wt 
> 


& 
x Darkened Window. 
a 
Mm 
£ 
= Light Window 
(Shode 74 Open) 
¢ 


a 


Exp. 24. June 28, 9:55 p. m. This experiment was arranged 
as indicated in the diagram above. All of the moths were % 
day old, 28 males were placed in the northwest corner and 28 
females in the southwest corner of the room. One window on 
the east was darkened, and the other had the shade lifted four 
feet. The objects were to see: 

(a) If both sexes would go to the light; 


190 Trans. Acad, Sci. of St. Louts 


(b) if one or the other sex would cross over and reach 
the opposite sex instead of following the light. 

(ec) if these moths would react in the same way to this 
arrangement of stimuli on successive days and 
nights, i. e., as their age and experience advanced. 


An examination at 3:30 a. m. revealed that 14 males, exactly 
one-half, had travelled to the lighted window, diagonally across 
the room from where they had been placed, and one had gone 
along the wall to the adjacent corner and mated with one of the 
females. Not one of the females had moved from where I had 
placed them. At 8 o’clock the next day examination showed all 
of the males (excepting the one in copulo) at the lighted win- 
dow, in the bright sunshine. None of the 28 females had reached 
the light; only four had attempted to do so, but had traveled 
only, 1, 2, 8, and 5 feet. This window faced the street with 
automobile lights also. 

At 9:15 a. m. all the moths were placed in their original posi- 
tions on the wall; 8 returned to the window before noon. It 
seems that they were now breaking down some of their. stiff 
instinets by responding to lights at periods that differed from 
the set rule. ‘These moths were in prime condition, a little more 
than one day old, when 8 out of 28 moved to the light in midday. 
If this reaction to light of this intensity is truly phototropic, 
we should rightfully expect to see all of them respond in the 
Same way, just as they all did to the rays of dawn in the pre- 
vious tests. In Exp. 21, the six males that responded to the 
light during the day were much older than these and, since they 
had failed to do so before, I attributed their reaction to their 
age and experience. The fact that these younger ones behaved 
similarly immediately thereafter leads one to wonder if there 
might be something in the season or the light conditions of these 
late June days which modified their action. 

At noon all of the males were returned to their original places; 
I then had to leave them until 9 p.m. At that time all of the 
males were again on the window and 15 of the 28 females were 
on the sash or near it. 

Exp. 25. June 29,10 p.m. This is a continuation of the last 
experiment, with the same room arrangement, but in addition 
to the 28 males and 28 females, 53 females were also placed at 
the southeast corner of the room. These 109 moths included: 28 


Experiments in Rhythmetic Periodicity 191 


males 114 days old, 13 females 14 day old, 28 females 11% days 
old, 20 females 2 days old, and 20 females 5 days old. The 
moths of each lot were given a distinguishing mark for their 
identification. The object of this experiment was to see at what 
age the females were more likely to be influenced by the light of 
the uncovered window. The males were retained in the room 
to serve as a check. At 8 a. m. next morning, all of the males 
were at the window, and the following females: 


Number’ Percent 


Age, Number attracted attracted 
days. used. tolight. to light. 
% 13 0 0 
1% 28 18 64 
2 20 16 80 
5 20 17 85 


This shows most remarkably that age is a factor in the activity 
of the females; the figures in the per cents column speak more 
distinctly than words. 

At 9 a. m. the moths were replaced in their respective corners ; 
they were all, of course, a half-day old in this test. Up to 
noon, 3 males (2 of which had made two flights and 1 had made 
one flight previously) moved to the window; these were replaced 
and the experiment left alone until evening. At 9 o’clock, the 
census revealed that all of the males were again at the window, 
fluttering excitedly about the pane. Of the 81 heavily laden 
females, 62 had left the wall in their respective corners and were 
making their way slowly eastward, vibrating the wings intensely 
as they crept, as though being slowly but irresistibly lured or 
even dragged across the floor toward the light. Only 3 had 
actually reached the goal, and were climbing to the frame. The 
females were of all ages as follows: 

Number Per cent 
Age, Number attracted attracted 


days. used. tolight. to light. 
1 2 54 
2 28 24 85 
244 20 17 85 
514 20 14 70 


192 Trans. Acad. Sci. of St. Louis 


Here is more evidence of delightful clearness; the moths 
which, when half a day younger, remained indifferent, now under 
identical surroundings, respond to the extent of 54 per cent of 
their number, to the light stimulus. The second group, those 
now two days old, had increased their efficiency from 64 to 85 
per cent; the third group, still in their prime, improved upon 
their old record only slightly, while the oldest, now verging on 
senescense, were beginning to wane. During the night 3 more 
females became travellers, and next morning three pairs of the 
moths were in copulo on the window sill. Unfortunately, I did 
not ascertain whether the air in the room was in motion. 


Exp. 26. June 29, 10:45 p.m. In the previous experiment, 
we found the males going to the window and the females follow- 
ing, but after all we do not know whether the latter responded 
to the light rays or followed the odor trail to the males. For 
this reason we wished to repeat this test in a room where no males 
were present, and to make the conclusions absolute, in a room 
where there was no possibility of male odors lingering about the 
windows. Therefore the family meekly submitted to ejection 
from still another room in the house, this time the living-room, 
which was transformed into an improvised laboratory. All 
windows were darkened excepting one in the southeast corner, 
likewise facing east, and 54 moths were placed on the wall in 
the northwest corner. There were 13 females 14 day old, 5 were 
one day, 17 were 2 days and 19 were 5 days of age. All were 
marked and placed on the wall at 10:45 p. m. 

The next morning revealed but slight activity during the 
night; only two moths (aged 2 and 5 days) had reached the 
window, three had moved about a foot toward it, and about @ 
dozen had crept upward a few inches on the wall. This seems, 
when compared with the previous test, a rather discouraging 
result. However, one must not lose sight of the fact that the 
others had rested all day and had done practically all of ther 
moving between 8 and 9 o’clock, while these had not even been 
placed on the wall until after that hour. 

At 9 a. m., all were replaced on the wall, but none moved to 
the light during the day. Between 8 and 9 p. m., their cus- 
tomary hour, their agitation began; 43 moved all or part Way © 
to the window; only 11 remained on the wall, and these moved 
slightly. Of course they were now one day older than recorded 


Experiments in Rhythmetic Periodicity 193 


above. Eventually all of the travelers reached the window or 
sash. Unfortunately the actual numbers in each class were lost, 
but all groups were represented, while in each group were from 
1 to 4 which failed to respond. The experiment adequately 
demonstrated that in a room without males or the possible odor 
of them, the females react to the light just the same as if the 
males were there; hence the light per se is the stimulus. 

Exp. 27. July 1. This was to be the final experiment of the 
season, so I took all the cynthia moths that I had on hand and 
placed them on the south wall of the third-floor laboratory. The 
light was admitted at only one window. I merely wanted to see 
how the moths of various ages, sexes and conditions would re- 
spond to the lure of the light. The lot consisted of: 

Normal moths: 8 females 2 days old, 6 females of unknown 
age, 6 males 2 days old, 17 males 4 days old. 

Moths with right antenna off: 3 females, 4 days old, 6 females 
7 days old. 

Moths with left antenna off: 5 females 2 days old, 3 females 
4 days old. 

Moths with both antennae off: 10 females 2 days old, 4 females 
4 days old. 

Moths with half of each antenna off: 2 females 2 days old, 3 
females 4 days old, 5 females 7 days old. 

Moths with paint-covered eyes: 7 males ¥y day old, 13 males 2 
days old, 7 males 3 days old, 15 females of unknown age, 13 fe- 
males 3 days old. 

These 133 marked moths were placed on the wall at 4 30 p. m., 
in time for them to become composed before their evening hour 
of activity. 

By 6:45 p. m., 22 moths (10 males and 12 females) were on 
the window; 6 of these were normal and 16 were mutilated, and 
in the lot were 2 blind males only % day old, for ye 
was the first night in this world, and 2 other blind males 3 days 
old, which of course had experienced twilight previously. These 
22 which responded about two hours earlier than their usual 
period of activity constituted about 17 per cent of the total popu- 
lation under experimentation. This test shows also that the 
moths are able to make the flight under the handicaps men- 
tioned above. In the entire lot 72 per cent were handicapped, 


194 Trans. Acad. Sci. of St. Louts 


and among those accomplishing this early flight 73 per cent were 
thus modifie 

These 22 fenton moths were put in a cage until I could 
return to them. At 7:30 I opened this cage and stationed myself 
to observe the conduct of the entire group during their busy 
hour. Within 15 minutes, 10 of them had succeeded in making 
their way to the window; at 7:52, when the last gleams of day- 
light were leaving the sky, 21 moths were fluttering about the 
window. During the next 3 minutes, 9 more joined them, At 
about this rate, more and more of them joined in the migration, 
until about 9 o’clock, when the excitement began to wane. At 
that time 66 were there, or about one-half of the population. 
The moon did not rise until 10:30. A census at 11 p. m. gave the 
following data: 


TABLE No. 6. 
No. in No. that Per 
Exp. Responded Cent 
Normal females 1 4 28 
a ales 2 22 96 
Females, right antenna off, 7 days..... 0 0 
Females, right ant off, 4 rtdels 0 4 
Females, left antenna off, 2 days...... 5 100 
Females, left antenna off, 4 days....... 3 100 
Females, all antenne off, 2 days........ 1 5 50 
Females, all antennz off, 4 days....... : 0 4 
Females, % h antenne off, 7 days 5 100 
Females, 4% both antennz off, 4 days 3 100 
Females, 4% th. antenne off, 2 days 4 2 100 
Males, blin 5 71 
Males, blind, 2 reed 13 8 61 
les, blind, 3 days 2 28 
Females, blind, 3 days 13 1 4 
Females, blind, ? days rT 1 7 

Summary of Table: 

Normal moths 37 26 70 
All moths, right antenna off........... 9 0 ® 
Females, left antenn: off, all ages 8 8 100 
Females, all antenne off, all ages...... 4 5 36 
Females, % both ante enne off, all ages 10 10 100 
Males, blind, all a 27 15 . 
emaies, blind, an 4 ages 28 2 uJ 


The summary of the data gives some highly interesting evi- 
dence. Of course the numbers are too small to be accorded much 
serious consideration, but nevertheless they are very interesting 
indicators. It appears at first as an unusual case of accident or 
chance that all moths with the right antenna off failed to come 

the window, while all moths of all ages with the left one am- 
putated, succeeded. However, these results conform nicely to 
the results of Loeb’s experiments with certain insects with anten- 


Experiments in Rhythmetic Periodicity 195 


nae removed. If the left antenna is removed, the insect moves 
in a circular direction to the right, and if the right one is re- 
moved, it turns to the left. Now the light came in at the window 
from the right of the insects’ position, and all of them lacking 
the left antenna moved toward the right into the influence of 
the light, while those lacking the right antenna did not drift 
into the path of light and hence did not succeed. Of the moths 
(all females) with both antennae entirely removed, one-third 
came to the light; this is as good a record as any group of able- 
bodied females has ever made for us. This clearly indicates that 
when the female does come to the light she receives the stimulus 
through some organ other than the antennae, although it, 
through mutilation, they are unequal, she may be unable cor- 
rectly to orient herself in making the journey. It is unfortu- 
nate that the lateness of the season prevented our having at 
hand enough males also to thoroughly test this question, but it 
seemed better to keep an adequate supply of them unmodified 
to serve as a check. This they did very well, responding to the 
light to the extent of 96 per cent of their number, thus proving 
that the conditions of the experiment were not at fault. 

The case of the ten females from 2 to 7 days old, with one- 
half of each antenna amputated, is the most perplexing. Since 
females seldom respond to the light to a greater extent than 25 
per cent, I cannot explain why these should have made 100 per 
cent response, except by mere meaningless chance or by some 
intricate arrangement of sense-organs in the basal portion of the 
antenna which we have not yet even suspected. 

The moths with paint-covered eyes made far better returns 
than had been expected; 55 per cent of the males and 7 per 
cent of the females found their way to the light. 

The puzzle remains, what combination of sensory responses 
in relation to environment really brings the sexes together? We 
see the males leaving the females and going to the light, there 
to find their mates, but evidently not following the odor and 
thereby arriving at the light. In this group, since there is so 
much greater response to light when the antennae are mutilated 
than when they are normal, it seems that normally the percep- 
tion of stimuli, either odor or light or both at the same time, 
creates a conflict of feelings in the creatures. If the antennae, 
the organs of perception, are removed, then there follows a 


196 Trans. Acad. Sci. of St. Lous 


stronger response to light, because odor is ruled out; if the eyes 
are blackened so that light is excluded, one ought to get better 
response to odor stimuli. The lack of material at the end of 
the season prevented me from putting this point to test. This 
could be done by blowing a stream of odor from one sex upon 
the other and when the insect is thus aroused, see whether it 
follows the odor trail to the source or flies away to the light 
instead. 


In the blind tests, without the artificial currents of air, the 
response to the light was surprisingly high, but this may have 
been due to faulty technique. When the moths were examined 
later, a few tiny cracks were perceptible in the hard paint on 
the eyes; this may have been sufficient to admit enough light to 
guide them in their flight. 


MeIndoo insists that the olfactory organs are not situated 
in the antennae. 


If we remove the antennae of males or females, and get better 
reactions to light because they can perceive no odors, and if 
then we blind others and get better olfactory responses because 
they are not distracted by light, would not that show the seat of 
the olfactory sense ? 


Experiments on Cecropia and Polyphemus in Reaction to Light. 


It seemed to me that if phototropism were the cause of the 
reaction of these moths to the light, we should find all of the 
moths of one age responding at the same time, and if after they 
had flown to the lighted area they were immediately replaced 
they would again react in unison, so that when the experiment 
ended, all would have made the same number of trips to the 
light. With this in mind, planned experiments with the fol- 
lowing technique. 


A room, 15 by 10 feet, had a small, uncovered window at one 
end; the opposite end was dimly lighted, closely resembling 
twilight. At this dark end, a blanket was tacked to the wall, to 
give a comfortable foothold to the moths. The insects were 
placed on this at the beginning of the experiment, and as soon 


EXPERIMENT A 


TABLE No. 7 


NORMAL CECROPIA, MALES 


Experiments Commenced May 29, 6:30 A. M., Ended May 31, 7 P. M. 


Date and Temperature 


5-30 5-31 
— ne, 60-68 °F Remarks 
A.M | P. M.* A. M.** 
ae Beas 
bos | 8 aR n ot besa Serbs 
507 3 Be Ne EP ae 
509 3 44, 11..... | AGRE AMES an Urges | [Ba’ A OARS OMAR, aS 
§12 3 ce Te Rae ae aN 
513 3 41 
514 3 te, ORE RUE a ae a” RR as 
611 3 GAS eos ees |) OSE Sarre 
454 6 
456 6 9 
| [3 vi 
Vase Ona e 3 
445 7 6s de 2 
451 7 S538 Sa 2 RON aetna toa 10 16 %’s made 97 flights 
442 Te oo Dy Reese ett CPG Mees Wea Ale tc ccecn sees 2,9 4 =o ene per male 
a 
Total. | of tarts 
\ \ | 
*At 11:30 all were placed on wall. No oheseration made until 7:00 A. M. next morni 
**All moths at einen replaced at 7:00 A. M. No observation made between 11:30 A. M. and 6:45 P. M. 


Aporpowag nomyjhyy ut spuaunsada 


L6T 


TABLE No. 8 
EXPERIMENT B 
Experiments Commenced June 3, 9:30 P. M., Ended June 6, 7:00 A. M. 
6-3 6-4 6-5 6-6 
Male Age 68-70 °F 70-80 °F 70-80 °F 70-80 °F Number 
No. Days of Remarks 
Responses 
P. M. A.M. | P. M.* A. M.** P. M. A. M. P, M. 
ie * hing ght Pe 3, 514, 8 74,9, 11, 1134]| 7 12 
27 OM Si... UB ee ae SORA RIOR TABS UR A ae 6 
19 aay a8. ipso stoen 7 me) a MEIGS) NAIM i ens a ae 4 
EN TS SANS aR nt CNET Gar tT aac | Rita Ae ey ye (Tee gs y ERED IPAS (os teeta i aR 6 
23 Oi... 344, 9...|. Pi ee ik ume cee Cee i 4 
Bhi ee a ee Bi 9.) Pa. Va a5, | 744, 9 1 Baiada eft Geechee hice 8 
30 i 8% 108% 3 ROP perce | Ben nd ec Cece uae | GER anssne Hevea 3 
; fs  aeataay 8 es iii | Died... Be Ali : 
36 2 URE i BN aA teehee ich eae a TORRID EN AN 6 
37 2 ouauley 3s Gre hal Peon eteda LIES oun Cave Bera Lei ate Ce Ra NE i st nt: 1 
40 LD RARENCRS OMS) OMG ACUMEN lene pea fy DA RB ee ae ae, oy | 1 
45 AES Daun av 314, 8%, 
9, 11 eee ie Baie |G | 3 Re ee vot ve. Gage |e Lo amp ir gly Uitte a bala 11 
46 3 sh ae Mig re TG | ERR an Geta Bet: ps ARO IR CSO ge 4 
TERUG Ese Sed al wie, hfs Wie, 8.055 Hh NW NG Ro Te age 5 
49 BA) ACY Te ea ee noe 3 
43 Be tas OSS ha CPT, A TED Nie SEG FA re A emt | er Ge Re ONY Neatek RC A aml 3 17 6's made 87 flights or 
5 2/17 flights per ao in 
OM ee iiied chee suds acces oad 87 temperature of 70-— 


*At 11:30 all were replaced on wall. No Pag age made until 7:00 A. M, next earns 
All moths at window replaced at 7:00 A. M. No observation made between 11:30 A. M. and 6:45 P. M. 


861 


sino ‘3g fo ‘wy ‘poop ‘suny, 


Experiments in Rhythmetic Periodicity 199 


as they had flown to the lighted area each was immediately re- 
placed on the blanket. 

The experiments A and B, recorded in Tables 7 and 8 for 
male cecropia moths show that males do not react similarly or 
simultaneously or an equal number of times, although condi- 
tions and handlings were maintained as nearly uniform as pos- 
sible. The column of totals reveals that the number of flights 
varied from 1 to 12, but there was no relation between the age 
of the individuals and the number of flights accomplished; 
moths young and old made both few and many flights. It is 
especially interesting, however, that all of the 33 males gave at 
least one reaction. 

During the daylight series of experiments (A), begun at 
6:30 a. m., some individuals reacted to the light within a half- 
hour, others were indifferent for varying lengths of time up 
to 13 hours. During the second series (B), begun in the eve- 
ning, the first ones responded within a few minutes, while 
others were motionless for 3, 6, 12 or even 45 and 53 hours, be- 
fore finally they were aroused and flew to the light. Not only 
was there great variation in the delay before their first flight, 
but even after the moths had once been aroused to action there 
was equally marked variation in the interval between their 
flights. 

It seems that if the definition of tropism actually is ‘‘a form 
of externally induced behavior in which the organism automa- 
tically so adjusts itself as to have morphologically symmetrical 
portions equally stimulated,’’ then why does not this external 
inducement treat all of the organisms that come under its in- 
fluence alike, when age and conditions are alike? 

The foregoing data were for the cecropia males. Tables 9 and 
10 give the results of similar tests of the females, at the same 
time and conditions. 

In the group of males, every individual in the lot responded 
to the call of the light (Tables 8 and 9). Among the females, 
there were five individuals which made absolutely no response 
during the entire period of experimentation. It happens that 
all of these were among the first lot, which were tested while 
the temperature was 64 to 68 F. Among those which were 
tested while the temperature was 70 to 80, every one of the 
females responded. Moreover, the latter averaged 444 flights 


TABLE 9 


EXPERIMENT C 
NORMAL CECROPIA, FEMALES 
Experiments Commenced May 29, 6:30 A. M., Terminated May 31, 7:00 P. M. 
Date and Temperature 
9 Age Number 
5-31 of ks 
No. | Dave Ve 8 Rendinsen | ‘ema 
A.M P.M | .M. P.M ] A.M P.M 

582 5 OM di || 43 414, 8, 11 , \| A 7 6 
Send I] UG P Dees eee I Be 
574 1] 1] None 
587 || | None normal fem 
500 {| 1 None sk 29 flights or .2 iit 12 
501 TES AOE NCG A 6i.. || || Died 1 flights per 9 with a 
506 9 H 1, 2,9 1] 4 perature of 64-68 
508 3 y CS a... \| | 9 
510 3 8 1% 1| 9 | My, 
499 3 TES EE apo STRICT Sila a | aa one 
455 } 7, 8, 9, 10, 11, \ | 

TM ia a: 2,7% 8 
Total | 1 29 


T 18 {0 wy ‘poop ‘sup. 


Sino 


TABLE 10 


EXPERIMENT D 
NORMAL CECROPIA, FEMALE 
Experiments Commenced June 3, 9:30 P. M., Terminated June 6, 7:00 A. M. 
6-3 6-4 6-5 6-6 Number 
x Age 68-70 °F 70-80 °F 70-80 °F 70-80 °F ° Remarks 
0. Days Responses 
P.M. A.M, P. M** A. M, P. M.* A.M. Pr. Mi, 

26 ‘ A Lp” Uy Ange | DER eS Dae ec) E t 2 
(GASES RSIRMSSG cama Real bri | Uaioe rs SOU RDM Tem “ove inee de | B 
ee Hi ek cee Noe oe ve, eee Wal ae EE Uh ere ae be a UNG ATU UCI rinen san" 1 
20 9%4.. RE BED ASS | REE ASS RRR) SS aRlereei Sta Uri | MOURN RRS TRICO, 8 Ce URC Nida 2 
eh, Se Aca: a4 hiss 0 OLN aha | PURE DEA aay SUSE RUS CEN 2 
32 -| 3h, 8, 8s made 63 flights 

MVC SOREN Es eee , oleyo nL BG Cece es Bun as 6 ie flights g re 
33 1 1034 ARR PGS I | ORE ete NINE ae Ge ea oles ies ee Nei b ecg oe 3 temperature 68-80 °F 
34 1 .| 344, 8%, 
os j 10% 3s "Big. Rigs Wie) le ek ea te a ll 24 aoe ae ate WU GRD CANE: hg: TunIC : 
39 2 ans Sou ee et oe eer, 1 eS ONES ects 
+ : Savew eS 4 8ig : Big eearlicsistv es goer et é “ays leas 354 od We eta Labi SUN oR aes eRioe, Gi) . 
50 2 RRR Saal Misptinand | a Cakes sian, Garey cc Parc Coe eee CHT 
44 4 ee 34, 8, 

CR Tn NS | NS ene ae We: TR 8 

Total. Roo EE a SSBC L SSE AD | SOR saris (bho dee mnie noes 63 


*No experiments were made or observations recorded on June 5, between 11:30 A. M. and 6:45 P. M. 
**The teh opm responded tot replaced on wall and no experiments were made 0; baer vations recorded before 10:00 A. M. next morning. It is strikingly 
strange that during this period 8:00 P. M. to 10:00 A. M. ne: xt day only one female reaponded. 


ipoporwag mowyshygy ur spuausada yg 


106 


202 Trans. Acad. Sci. of St. Louis 


each, as compared with 214 flights each for those of the first lot 
when the weather was ten degrees cooler. This indicates a 
marked increase in activity during the warmer days, but since 
the males which were under experimentation at the same time 
showed a slight decrease in activity at that time, the difference 
is probably due to something other than temperature. 


These, like the males, showed no tendency to move simultane- 
ously ; some flew promptly and often, and others waited as long 
as 48 hours before making a start or repeating a flight. 


An attempt was made to study the reaction to light of blind 
cecropias. This work was done simultaneously with Exps. A 
and C. The eyes of 17 males and 10 females (see Table 11) 
were painted with two coats of black stove enamel; this, it 
seemed to me, should have permanently ended their vision with- 
out causing them to suffer the shock of mutilation, but I have 
no guarantee that it actually did so. The males under these con- 
ditions averaged just one-half the number of flights accomplished 
by normal males, in the same place and time; out of the 17, Table 
F, only 4 failed to respond. This shows at least that some were 
materially affected by the change, although the surprising thing 
is that any of them found the light. Of the females, only 4 out of 
10 found their way to the light. This amount of efficiency may 
indicate the presence of some unknown sense whose very exist- 
ence we have not suspected, but I am more inclined to attribute it 
to faulty technique, such as cracks forming in the painted area. 
I should like very much to see these experiments repeated, if 
some method could be devised which would be more efficient than 
painting the eyes without causing a severe shock to the moths. If 
the rhythmic periodicity of these creatures is a thing inherently 
fixed within their beings as a physiological process instead of a 
psychological one, then we should see those deprived of light 
stimulus reacting at certain periods of the day. Even after 
making generous allowance for faulty technique, I see no indi- 
eation of this concerted reaction. 


The same work was carried on simultaneously with polyphe- 
mus males and females. They displayed much greater varia- 
tion in the number of trips to the light than did the cecropias. 
Among the males, some waited long and seemed satisfied with one 
trip; others kept coming to the light as fast as I could carry 


TABLE No. 11 
EXPERIMENT E : BLIND FEMALE CECROPIAS 
Time, Temperature, Technique Same as Table 9 
soy , 5-29 I 5-30 I 5-31 | Number 
oO. ge 0 
A.M P.M. A. M. P. M. | A. M. P. M. Responses 
592 , i} Vie a he Reb Ore web \| waarwite Ce: None 
We a a, \| Hei cree so Gee koi None 
579 \| {| None 
577 \| AES PORT SS Lie PSE enc ae None 
580 \| 6%.. ee ee ree 1 
540 1 eG Cate Ea Hig eet ae eee ya eae None 
498 3 \\ oreo re CE Une eh aca.) None 
482 3 Oe. Weaiz ea I PE Saou, 2 
477 3 | Beit EGE OLLI US WACOM HAUS ea None | 10 blind 9's made 4 
| \ i pb cig an average of 4/10 
UM es id oc eee scab ce cee wreaths oak Wie Chee ec oe te ee bee oe CNP a lala w lle Ee IER TGs 4 per 9. 
EXPERIMENT F BLIND MALE pct ont 
Experiment Set on He at 11:15 P. M., First Observations ve Morning at 7:00 A. M. 
Temperature, Technique Same as Table 
ae, eam | ve 
on % ce | SS © Tae eat ean ee oe Sasi 
544 1 he) | 2 
543 1 7 | Se 2. 1} HI ; 
542 1 | \| ne Ree eats Pe Pea: I 
541 1 10 | Wake... 
532 1 7, 1406). 5055; ll. \| WH ee woke \ Lee A a ae | 
531 1 As Big 44 7 
530 1 Scat ce 634, 74...... | UP aay aoe 9 pete. as | : ga | 
520 1 ids ht ee \ I] Frerteer ees Sy GSP Ne oes Nina 
483 3 Be ae 514, 64, 744..|| 11144......... a ae i 7 || 
480 3 t wees DBM 4% thr 3 Cat Ae } 
ok ; hee oe eed Mech ede 4% | Wi ieiiaipemdonec ot ache abies aes 
462 6 | \| \| || None a blind %’s made 52 
Total. | \ | I 52 bt ane leas of 31/17 


hporporag njamyjhyy ur spuaunsada gy 


£06 


204 Trans. Acad. Sci. of St. Louis 


them back, and would have come oftener if I could have kept up 
with their speed. The number of trips made by the 17 males 
were as follows: 


Trips. No. of Males. 
i te S$ 7 

10 to 19 6 

20 to 29 1 

30 to 39 1 

40 to 42 2 


The high or low number of reactions did not occur on any one 
day, so one cannot say that conditions of environment caused 
them. 

The polyphemus females showed surprising promptness in 
flying to the light, but the experiment was set at 9 p. m., the hour 
at which the moths become busy. In fact, 7 of the 12 females 
had responded within the first 45 minutes, in spite of the fact 
that the only light was that which came in at the third floor 
window from the street lights below. They did not continue 
their activity, however; one of them remained absolutely indif- 
ferent during the three days of experimentation, 9 responded 
only once or twice, and the other three made 7, 10 and 18 flights 
respectively. The very fact that some females should respond 
so many times would lead one to suspect that learning or the 
innate possibilities to reaction is much more pronounced in some 
than in others. These simple experiments reveal that there is 
abundant variation in their reactions to light stimuli. Photo- 
tropism, at least, does not victimize the entire population at the 
same time and in the same way. 


The Light of Dawn. 


The time of flight of the majority of wild cecropias was the 
hour of dawn, about 3:30 to 4:30. This hour was divided into 
thirds, and records kept for eight days of the number of moths 
that came in during the darkest 20 minutes, the medium and the 
lightest 20 minutes, which was the full morning light just be- 
fore sunrise. 


Experiments in Rhythmetic Periodicity 205 
May. 3:30t03:50 3:50t04:10 4:10to4:30 Total 
21 25 31 37 


93 

22 58 30 11 99 
23 5 2 1 8 
24 33 28 12 73 
25 13 22 6 41 
27 16 4] 12 69 
28 aes 21 12 33 
29 16 6 6 28 
ees 166 181 97 444 


Thus, of these 444 males, 38 per cent came in during the 20 
minutes when the light was scarcely distinguishable from night, 
and 40 per cent during the medium light, leaving only 22 per 
cent of the moths abroad as the full light of day approached. 
We are safe in assuming that the majority of those which ar- 
rived after daybreak had probably aroused themselves and 
started on their journey during the darker portions of the hour. 
Some further records were kept to see if this distribution over 
the period covered the various classes, the wild old males, the 
wild young males and the bred males, but no evidence was 
found to indicate that one period influenced one class more 
than another; all three periods contained members of all three 
groups. 

I have frequently referred to the cecropias coming in at dawn. 
This would imply that the moths become active with the first 
streaks of light, which was not true, for at 3:30 a, m. the blackest 
night prevails, that proverbial blackness which precedes the 
dawn. This brings up the question, ‘‘When does dawn begin 
and when does it end?’’ At first this seems a foolish question, 
but since these creatures are very sensitive to light, and it is a 
factor of so great importance in their existence, this is an im- 
portant question. It is difficult indeed to believe that light 
alone at 3:30 a. m., can be the stimulus to their action, when it 
seems to the human eye in no wise different from the light of 
other night hours. : 

A ecritie of course might say, that this is the hour of their 
activity, and come what may, when that period recurs they must 
and will fly, and they ean not evade it. If he made that state- 
ment about cynthias, he would be more nearly right, but it is 
not true for cecropias, for their movements are actuated not by 


206 Trans. Acad. Sci. of St. Louis 


the hands of the clock, but by optimum conditions of light. This 
has been adequately proven in the experiments. 

In order carefully to study the light conditions of this period 
I set the alarm at 3:25*, and was on the roof at 3:30, waiting 
for the first moth to aprive: At that time there was in my 
estimation, absolute darkness, broken only by the stars and arti- 
ficial lights of the city. My brief notes were made only by 
means of a flashlight, which I could turn on for only an instant. 
Not until 4:08 did it become sufficiently light that I could 
elumsily guide my pencil on the paper without the aid of the 
flashlight. By the time their flight ceased, about 4:30, the gray 
light of day awaited the sunrise. Hence, to my senses, dawn was 
at about 4 a. m. Of course it is easy to understand that if the 
conditions at 3:30 aroused the moths to flight, those which were 
near would come in at once, while those which came from great 
distances would arrive later, unless the dazzling light of sunrise 
overtook them en route and stupified or lulled them into quiet 
for the day. This sounds logical, yet in my attempts at imi- 
tating in the laboratory this condition of intense darkness, I 
eould get no reaction, but when I produced a condition of light 
similar to that at 4 o’clock, there was some response. Of course 
the artificial lights of the city modified the darkness, but they 
had been there all night, as had also the females in the cages, 
which were emanating their odors from my windows all through 
the night when no males came in. Hence it seems that in na- 
ture there is an optimum condition of diffused light to which 
alone the cecropias react. Some supersensitive males can per- 
ceive the coming of the dawn before it is evident to others; 
some are so dull that the light of day is not perceived until it 
is well upon them, and come in at the last end of the proces- 
sion, in very human fashion. Then there is the great class 
of respectable citizens who do the right thing at the right time, 
and come in midway in the period. Then there is the excep- 
tional individual who reacts to the light he sees or thinks he 
sees long before his fellows. Lastly there are those of dull sen- 
sibilities who never arrive at the goal; how great this horde is 
I shall never know. So while the moths as a class respond to 4 
certain intensity of light, their response is modified by individ- 
ual temperament. 


*On many nights, as the data show, I was up on the roof all —_ 
and —- that (with the exceptions recorded) none came in before 


FINAL SUMMARY. 


A few outstanding facts may be gleaned from the foregoing 
pages, as follows: 

1. The sex life of the various species of Saturniid moths is 
very definitely interlocked with rhythmic periodicity, and that 
rhythmie periodicity is affected by conditions of light. 

2. During the period of their flight, recurring once in each 
cycle of twenty-four hours, the males fly to the females from 
different distances, varying from a few yards to a maximum 
distance of three miles. (No greater flights were attempted.) 

3. The various distractions encountered en route, city street 
and automobile lights, house-tops, street odors, city smoke anc 
beating rains offer no hindrance to males responding to the at 
traction of the females. 

The work shows that the number of marked males that fly 
to the females is in inverse ratio to the distance from the point 
of liberation. 

5. Evidence throughout the experiments proves that the 
males reach the females by odor perception, and that wind is 
the agent by which the odor is carried. When the males are 
liberated elsewhere than in a current of air blowing direct from 
the females, few or none find the female. 

6. The general term ‘‘night fliers’’ should not be applied 
to these moths, for each species has its own brief period of flight 
during the cycle of twenty-four hours. The moonlight some- 
times influences the period of flight in some species. 

7. While odor is the influencing medium inducing the nup- 
tial flight, the attraction cannot be termed chemotropism, 
since trial and error method play an enormous part in locating 
and finding the female. 

8. The male is an ardent lover, and while the females are 
often inactive, not all are mere bundles of inactive, odoriferous 
matter, but some females strongly display sex emotions. 

9. Each species regularly has its short period of activity. 
This rhythmie periodicity can be changed to a considerable de- 
gree in Cecropia by simulating dawn conditions at high noon. 
In Cynthia, the hour of activity is more deeply set and cannot 
be changed so readily ; therefore we think Cynthia is phylogenet- 
ically the older of the two species. The fact that the various 


208 Trans. Acad. Sct. of St. Louis 


species of Saturniids in one locality have different periods of 
flight helps, of course, to keep the species from interbreeding. 

10. The seat of odor perception is probably located in the 
antennae. Complete removal of these appendages renders the 
male incapable of finding the female. The part of the an- 
tenna containing this sense organ is undoubtedly the basal re- 
gion, since removal of only a portion of each antenna does not 
impede the action of the male, and neither does blinding the 
eyes of the males adversely affect it. 

11. Light rays of certain intensities exert greater influence 
in first arousing the males of all four species than do females, 
for they will often ignore a nearby female to fly to a stream of 
light coming in at a distant window. While the heavily ova- 
laden females are supposed to be more or less sessile, they too 
attempt, in a goodly portion of cases, to struggle (they are too 
heavy to fly) to the light. 

Throughout these pages the reader is often reminded of the 
erudity of the technique, of the improvised apparatus, and 
the limitations encountered in turning one’s home into a Sa- 
turniid laboratory. By this time the thought doubtless enters 
the mind of the reader that experimental work on light reac- 
tions, odor responses and wind velocity should have the benefit 
of a well appointed laboratory. The writer had not gotten far 
into the experiments before he keenly felt the need of such ap- 
paratus, But making the most of any material at hand, he suc- 
ceeded without refined machinery in clearing up several puzzling 
problems in the lives of these mysterious creatures. 

However, the last word has not been said on sex attraction 
and rhythmic periodicity in these moths. Some of the problems 
can be solved with crude, improvised apparatus, and others re- 
quire the use of the highly technical apparatus of a psycholog- 
ical laboratory. From time to time during the course of the 
work, I jotted down these unsolved problems, and I record them 
here in the hope that some one with adequate facilities will un- 
dertake their solution. 

Long distant experiments, five- or ten-mile flights, with 4 
careful study of wind direction and velocity, and a study of the 
relation of wind velocity to speed of flight. 

Horizontal flight vs. vertical flight. In these tests all the 
work was done on a horizontal plane. In a vertical test flight 


Summary and Discussion 209 


the females could be placed on the roof of a very high office 
building and the males liberated on the street immediately below. 

Rhythmic periodicity in relation to sleep, hypnosis, catalepsy, 
lethargy and wakefulness. 

Differences of odors given off by the sexes of each species. 

Homing flights in brisk, cool winds of early spring, and in 
the warm breezes of summer. 

The function of the eyes. Their eyes shine with cat-like bril- 
lianey at night, but since they need not eyes for either food or 
mating, what can be their use besides perception of light? 

If the rhythmic periodicity in certain species is fixed and 
cannot be changed by experimentation, does this set rhythm 
vary in different strains of the same species (i. e., material from 
different localities) ? 

Effect of temperature on the action of the odor glands, i. e., 
does an increase of the temperature of the wind passing over a 
female increase the emanations? 

Experiments in progressive liberation ; liberate various lots of 
moths in a favorable wind, at intervals of an hour, and at various 
distances, and then time the returns. A concrete example would 
be to liberate many male prometheas at 2:30, 3:30, 4:30, and 
5:30 p. m., at distances of 2, 114, 1 and 14 mile respectively. 

Experiments in response to moving lights in contrast to sta- 
tionary lights. é 

Rule out light completely, and see if odor plus wind excite 
response. 

Reaction of males to odor of females of other species. 


DISCUSSION OF SENSES 


The five senses possessed by Man may also reasonably be at- 
tributed to most of the insects. In the Saturniids, however, the 
sense of taste is eliminated, since they take no food. This leaves 
only four senses of which we have positive knowledge: hearing, 
seeing, touching and smelling, for the guidance of the males of 
these moths when they fare forth in their quest of mates. We 
have seen that the males travel distances up to three miles to 
reach the females. They set out when light conditions reach 
the intensity at which their species is aroused to activity. I have 
no reason to believe other than that this light perception is re- 


210 Trans. Acad. Sct. of St. Lous 


ceived by the eyes. The light condition perceived by the eyes 
influences the moth to the activity of promiscuous flight by 
which he comes sooner or later into the odor stream of the fe- 
males. This odor is perceived by the organs of olfaction prob- 
ably situated in the antennae. Under natural conditions the 
sense of touch might assist in finally bringing the sexes to- 
gether, but this is only secondary, since I have seen males try- 
ing to mate with females inside a wire cage where contact was 
impossible. Sometimes the vibration of the female’s wings 
against the cage produces a musical sound, but in the open I 
doubt if they produce more than a vague rustling. No other 
evidence has at any time been observed which would indicate 
the functioning of auditory powers in the meeting of the sexes; 
nothing has indicated the presence of sounds outside the range 
of the ear of Man. This, then, reduces the number of senses in- 
volved in the coming together to two, seeing and smelling. We 
must not forget that without a condition of light to arouse the 
males to flight, and without wind to earry the odor which they 
follow in flight, there is no mating. 

Mayer thinks that the attraction of the male to the female 
promothea is due to chemotaxis. If following an odor trail to 
its source by hit or miss methods is chemotaxis, then the term 
may stand. If I walk along the street and catch a whiff of 
boiling sauer kraut, and poke my head into several restaurants 
until I find the one which stews the kraut, my action could 
hardly be called chemotaxis. If, however. you only saw me snif 
and enter the last restaurant without having seen me explore 
the others, you would interpret the behavior as chemotaxis. 
Mayer comes upon the scene and, finding males about his cages, 
he immediately says ‘‘chemotaxis’’; had he singled out num- 
bered or individual males, and with note-book in hand recorded 
their gyrations to and fro, up and down, in and around, leaving 
and returning, he would dispense with this term and simply 
describe the action as trial and error in response to odor. 

While Mayer and Soule say that the phenomenon which they 
witnessed in C. promethea and P. dispar, is chemotaxis, they 
surely do not mean to use the term in the sense of Loeb. 
They really mean finding the female by sense of yet for ber 
say: ‘‘frequently we have observed a male flying 
the wind until he passed by the side of and beyond the female, 


Summary and Discussion 211 


where he would often remain poised on the wings and the wind 
would drift him back until he came leeward to the female, when 
a few vigorous strokes of his wings would bring him more or 
less toward her again.’’. . . ‘‘In other words, speaking of the 
male being attracted and ferreting out the female in these two 
species of moths, the male pursued the method of trial and error 
so ably shown by Jennings to be prevalent in the animal king- 
dom.”’ 

Turner has shown that Saturniid moths, polyphemus and 
cecropia, perceive sounds, and moreover have been taught to 
associate certain sounds with pain. It seems to me that hearing 
in these creatures is for the purpose of avoiding enemies, and 
not to locate mates. I cannot agree with Mr. Frank E. Lutz* 
when he says: ‘‘In the case of some moths, the males are sup- 
posed to locate the females by odor. . . . Incidentally, it may be 
said that none of the experiments believed to have demonstrated 
that odor is the guiding factor in the case of moths, have abso- 
lutely ruled out sound, and male moths have antennae quite as 
plumose, apparently, as well fitted to receive sounds, as those 
of male mosquitoes.’’ 

I think my simple experiments where males were in close 
proximity to females in the same cages, and mating did not oc- 
cur, because there was no wind to carry the female odor, demon- 
strated the error of this view. It might be possible for the 
female moth to emit sounds that transcend the human ear, but 
surely it would influence the male if such sounds were emitted 
by the female when he was only an inch or two away. 
Likewise in the glass box experiments, where the females could 
have emitted sounds and probably would have done so at this 
time if they ever do so, to attract the males, we see perfect indif- 
ference so long as the air is motionless. Again it seems logical to 
assume that a five- or six-day old female would be more profi- 
cient in the art of communication than one a few hours old if 
her attractiveness depended upon audible expression. It is 
well known that fresh, young ones wield the greater sex attrac- 
tion. Of course Mr. Lutz will admit that something other than 
sound excites the males to copulation when he remembers the 
work of Freiling! and of Kellog? on the silkworm moths, Bombyx 

*Bull. Am. Mus. Nat. Hist. agli 1924 
Dp. a 


1Quoted by McIndoo, loc. Li 
2Biol. Bull. 12: 152-154. 1907. 


212 Trans. Acad. Sci. of St. Louis 


mori. The former made a careful study of the scent producing 
organ of this moth, and considers it the most highly developed 
scent producing organ in the Lepidoptera. With pieces of filter 
paper he succeeded in drawing from these saes some of the secre- 
tion, and then placed the paper in front of freshly emerged 
males. The males at once threw themselves upon it and behaved 
as if the paper were a female. Kellogg obtained similar results, 
and says: ‘‘If the cut out scent glands are put by the side of 
but a little apart from the female from which they were taken, 
the male always neglects the nearby live female and goes di- 
rectly to the scent glands’’ and tries to copulate with them. 


Of the butterfly, Pieris protodice, Rau* says of a pair that 
were trying to remate after having separated, ‘‘The female 
dropped several inches to a lower stratum of leaves and re- 
mained for a few seconds, and then darted away. I expected the 
male to go in hot pursuit; instead, for the next ten minutes 
while the female was dancing over some shrubs a hundred yards 
away, this male was frantically going in and out among the 
leaves in the spot where the female had paused.’’ His frantic 
search was pathetic to see, while a short distance away the fe- 
male was dancing in full view. If the attraction were sight or 
hearing, he could easily have followed her, but the only thing 
that held him was the odor left by the female in the bushes. 


Fabre, in Chapter XI of ‘‘The Life of the Caterpillar’’ is 
much impressed with the behavior of the males of several species 
of moths nearly akin to the material experimented upon in this 
paper. In order to give the foundation for some of his con- 
clusions we here give details from his experiments. 


A captive female of the ‘‘Great Peacock’? moth brought 
hordes of males ‘‘coming from every direction.’’ He removed 
the antennae of six males that came in, let them fly out at lei- 
sure: and then apologizes because only one returned. In the 
light of the experiments of Kellogg, Mayer, myself and others, 
it is surprising that even one returned. I suspect that the one 
never got far from the room, and the find was accidental. In 
a second experiment in a similar situation, involving 16 an- 
tennaless males, none returned. In a third test, 14 marked 
males with full antennae were permitted to escape from the 


3Journ. Anim. Behav. 6, 367, 1916. 


Summary and Discussion 213 


room; of these, only two returned later. This fact worried 
Fabre greatly, and he tried to account for the non return of 
the twelve by the surmise that the ‘‘Great Peacock is worn out 
by the ardours of pairing time.’’ He forgot for the moment 
that the two that did return were under the same strees of 
pairing time. Fabre says that they lived only two or three days 
and in the same breath says that the female lived eight days. 
It seems probable, therefore, that their failure to return was 
due to other influences than short life. 

Perhaps Fabre’s reluctance in accepting odor and wind as 
the factors which bring them together is due to his impression 
that they came from all directions. Without careful outdoor 
observations, how could he tell but that the behavior was the 
same as Mayer and Soule found for promethea flying against 
the wind as mentioned above. 

Fabre, however, at one period in his peacock work, really 
suspected odor as the agent, but when males were still attracted 
ie females even when he placed napthaline in the room, his 

“‘eonfidence in the olfactory explanation is shaken.’’ He for 
the time forgot that the napthaline odor meant nothing pro or 
con in the life of this moth; it was something entirely outside 
its experience in the natural world. But really Fabre must have 
thought better of the ‘‘olfactory explanation’’ than he was will- 
ing to admit, because next year when he got poor results he 
says: ‘‘low temperature is unfavorable to the tell-tale effluvia, 
which might be enhanced by warmth and decreased by cold, as 
happens with scents.”’ 

The third year he got large numbers to fly to the females; he 
moved the latter about each morning and then says: ‘‘all of 
these sudden displacements contrived to se seekers off their 
scent do not trouble the moths in the least.’’ Even then he was 
not ready to give odor and odor perception any credit, for he 
suspected ‘‘wireless telegraphy by means of Hertzian waves is 
the means for attracting the males.’’ He soon rejected the idea 
of wireless telegraphy as a means for attracting the males, when 
he lodged females in air-tight boxes of various materials and 
got no males to respond, but he did get them to come when he 
placed the females in poorly closed and cracked receptacles. In 
his work on the Lesser Peacock moth, Aitacus pavoma minor, 
he says they arrived ‘‘with a tortuous flight.’’ The flight, it 


214 Trans. Acad. Sci. of St. Louis 


seems to me, would not need to be tortuous if the moths were 
flying with the wind, responding to a wireless telegraphic mes- 
sage. 

His next species for study was the oak-eggar or banded monk 
moth. A female brought males ‘‘hurrying from all directions-’’ 
about sixty keeping up their frenzied movements for three 
hours. He found that in this species also the males would find 
the females hidden in various kinds of receptacles, provided 
they were not too tightly closed, but they also did not find them 
in vessels hermetically sealed. Fabre then placed stenches of 
various kinds near the female in such abundance that he nearly 
asphyxiated her, thinking thereby to make her unrecognizable 
to the males. Numerous males arrived just the same, and made 
desperate efforts to reach her. Fabre then placed the female 
in a bell-jar on the window ledge, in full view of the incoming 
males, and threw the old wire cage upon which she had rested 
into a far dark corner of the room. The incoming males com- 
pletely ignored the female in full sight and flew to the far 
eorner of the room, and spent all the afternoon dancing around 
the deserted home which had held the prisoner some hours be- 
fore. Of course since it seems improbable that the old wire 
dome threw out Hertzian waves to which the males responded, 
Fabre concludes that ‘‘it is smell therefore that guides the 
moths, that gives them information at a distance.’’ Fabre then 
playfully placed his females for various periods on glass, wood, 
marble and cloth, and watched the males come to the objects, 
attracted there by the odor left by the female. He gives wind 
credit for naught, says nothing about it except of its impotence 
in the behavior of the moths. He does not face the final ques- 
tion of why the males came to that very room in that very 
house, if it were not that some of the odor-laden air passed out 
of the house and mingled with the passing winds. He concludes: 
‘*But what we are to say of the great peacock and the banded 
monk making their way to the female born in captivity? They 
hasten from the ends of the horizon. What do they perceive at 
that distance? Is it really an odor as our physiology under- 
stands the word? I eannot bring myself to believe it. * * For 
all his finess of scent the dog is incapable of such a feat, which 
is performed by the moth, who is put off neither by distance, nor 
the lack of any traces out-of-doors of the female hatched on my 


Summary and Discussion 215 


table.’”’ Unfortunately, he has no actual knowledge of whence 
they came or how far. Because he suspects that they travel very 
great distances, so great in fact that he cannot conceive that 
odors can travel so far, he tries to account for the behavior in 
new and mysterious ways, for he says: ‘‘Like light, odor has its 
X-rays. Should science one day, instructed by the insect, en- 
dow us with a radiograph of smells, this artificial nose will open 
out to us a world of marvels.’’ 

No new device now seems needed to open up a new world of 
marvels in this instance. My investigations show clearly that 
there is a limit to the distance males can travel to reach the 
females. The further away from the females they are liberated, 
the fewer will return. Fewer will return from three miles than 
from a.half-mile, and those which do make the long distance are 
exceptional individuals. Without wind bearing the female odor 
there would be no attraction of the males. It is easy for me to 
believe this, since I have myself repeatedly caught whiffs of 
cecropia odor on the breeze, although my olfactory organs are 
not especially attuned to these emanations. O. W. Richards* in 
speaking of Mayer’s work on Callosamia promethea, makes this 
very pertinent remark: ‘‘The distance that males are attracted 
is probably often exaggerated and, in this connection it must be 
remembered that the males of these forms have often a very 
erratic flight, coursing about in all directions.’’ I judge, from 
observations in the laboratory, that they are inactive until the 
time for flight, and then fly at random until they find an odor 
trail 


Fabre and others constantly remind us that there is no sim- 
ilarity between our sense of olfaction and that of the insects, but 
Belloncif finds, in studying in a comparative way the olfactory 
lobe of the lower vertebrates and the antennary lobe of insects, 
that the histological structures of these organs in the arthropoda 
have a very close relation to that of the olfactory lobe of verte- 
brates, and concludes therefrom a physiological if not a mor- 
phological homology. Forel is willing to admit ‘‘that the olfae- 
tory bulb and the nasal mucuous membrane of the vertebrates 
are derived from the invagination of the antenna and the an- 
peaeary ganglion of an invertebrate. The nerve terminations, 


a. Reviews 2:320. 1927. 
+Cited by Forel, Senses of Insects, p. 96. 


216 Trans. Acad. Sci. of St. Louts 


formerly protruding, are sunk in a eavity which is placed in 
communication with the pulmonary organ of respiration, which 
allows of a current of air continually renewed to bring odors to 
them.’’ ‘‘For my part, I believe that this homology is true. 
Then the antennary ganglion will become the olfactory bulb, 
its nerve terminations will be the numerous little olfactory 
nerves, the antennary nerve will become the tractus olfactorius 
and the antennary cerebral lobe will become the olfactory lobe.’ 


‘‘But the antennae of insects are an olfactory organ turned 
inside out, prominent in space and certainly very mobile. This 
certainly allows us to suppose that the sense of smell may be 
much more relational than ours, that the sensations thence de- 
rived give them ideas of space and direction which may be 
qualitively different from ours.’’ ‘‘In reality a sense of smell 
which admits of distinguishing space is a kind of sixth sense 
very difficult for us to describe. But all evidence points to the 
fact that insects with mobile antennae have such a sense. In 
this way the sense of smell directs them much better than mere 
perception of odors. This fact also explains how ants distin- 
guish the right side from the left side, the front from the back, 
by their sense of smell, and know when following a track or a 
trace, in what direction they are following it. Finally» pur- 
suant to the laws of association, it allows insects an olfactive 
memory of places such as relational sense alone posesses.”’ 


It is gratifying indeed to find that comparative anatomy thus 
gives us morphological substantiation for our findings in the 
field. Forel says, ‘‘A sense of smell which admits of distinguish- 
ing space is a kind of sixth sense very difficult for us to de- 
seribe.’’ It may be difficult in the case of the tiny creatures, 
ants, with which he worked, but a little careful imagining on 4 
— scale and comparing with other sense organs will make it 

ear. 


Among our own five senses, only three—sight, hearing and 
possibly smell—bring us information on distance and direction 
of distant objects; touch and taste have no part in this. Let 
us consider the simple mechanics of these three organs in our- 
selves. We receive visual impressions of an object by the turn- 
ing of the eye, the adjustment of the muscles, in that direction; 
we can estimate distances only by the muscular converging of 


Summary and Discussion 217 


the two eyes. This is a marvelous feat. We can tell the direc- 
tion whence comes a sound only by turning the head to and 
fro and focusing, as it were, the two ears on the sound. This 
seems unbelievable, yet we do it every day. In like manner 
we turn our heads this way and that in an attempt to de- 
termine from which direction the odor is strongest, or we feel 
the breeze, the vehicle of odor. The olfactory apparatus with 
which we are now equipped functions very poorly in helping 
to determine the direction of an object emitting an odor. Our 
receiving organ is merely a single immovable area of mucous 
membrane, within the head, where the air drawn in by respira- 
tion may touch it. Now let us imagine ourselves equipped with 
such olfactory organs as he ingeniously describes for these 
moths, ‘‘ a branching olfactory system turned inside out.’’ This 
would be a pair of external olfactory organs, much branched, 
symmetrically placed on the body as are our eyes and ears, 
mobile as are our eyes, and lastly, extending out in front of 
us one-fifth the length of our bodies. It is easy now to under- 
stand how such an apparatus could serve the organism better 
than either visual or auditory powers (as we know them) in 
guiding it to the source of the emanations. There is reason to 
believe that wonders would be accomplished by means of such 
a mechanism which would far exceed the marvels of sight and 
hearing. But, we must not forget, while this apparatus would 
be more powerful or efficient in detecting directions, its scope 
would be limited to a narrower field, because, unlike light rays 
or sound waves, which radiate in circles, odors are carried on the 
wind in a stream in only one direction. The greatest distance at 
which Man’s degenerate olfactory sense will function is not 
known to me, but I once heard a man, whose scientific accuracy 
could be relied upon, say that in the wilds of Montana, where 
only wood was used for fuel, he had often smelled coal smoke 
from a train from a distance of fourteen miles, in the clear air. 

Thus the ‘‘magie’’ and ‘‘mysterious sixth sense’’ which have 
been adduced to account for the attraction of these moths to their 
mates may readily be brought within our comprehension. I 
still maintain, however, that the creatures do not come ‘‘from 
the ends of the earth,’’ but that their flight in this quest is 
limited by the area of dissemination of odor in currents of air. 


218 Trans. Acad. Sct. of St. Louis 


DISCUSSION OF RHYTHMIC PERIODICITY. 


Bouvier, in his already mentioned chapter on ‘‘Rhythms,’’ in 
agreeing with Loeb, says that in certain moths ‘‘This periodicity 
is independent of actual luminous stimulations.’’ To some ex- 
tent the experiments of Reaumur, whom he quotes, influences 
this decision. Reaumur says of moths enclosed in boxes and 
eages that during the day they are quiet in their prison, ‘‘pass- 
ing hours and often days without moving in the same place. 
But when night has come and even before the sun is set, they 
move their wings and fly as much as the box will permit.’”’ Of 
course this quotation seems contradictory inasmuch as they can- 
not spend days in their prison without moving and at the same 
time become active when night comes. What probably hap- 
pened with these moths was that some were placed in light-tight 
boxes, and these spent days without moving, while those which 
were in cages, where natural light could penetrate, responded 
to the dim rays of optimum intensity. By referring to our 
experiments, one can readily see that this is what happened in 
cynthia, cecropia and polyphemus. In tests in light-tight con- 
tainers, they did not move from their marked places for several 
days at a time, but became active only when dim light was ad- 
mitted. Obviously the statement that ‘‘ periodicity is independ- 
ent of actual luminous stimulations’’ does not hold for the above 
three species. Despite the fact that Reaumur’s statement, quoted 
above, gives us no assurance that his ‘‘boxes and cages’’ were 
light-proof, and hence there is nothing to show that the moths 
react in absolute darkness, Bouvier goes on to say that ‘‘this is 
a periodicity acquired by the organism. This is graven upon 
the being in the course of generations under the phototropic 
influence of periodical luminous stimulations and may show it- 
self today without their intervention. It has separated itself 
from the stimulating actions which have produced it.’’ 

Also from Loeb’s observations on the sphinx moth carried 
on ‘‘during two or three days,’’ Bouvier concludes: ‘‘Thus the 
periodicity appears to us to be manifest and independent of 
luminous variations.’’ But unfortunately, in the next para- 
graph, also based on the experiments of Reaumur and Loeb, he 
concludes: ‘‘Thus understood, the periodicity shows itself to 
be a simple manifestation of phototropism with these insects.” 


Summary and Discussion 219 


Concerning Roubaud’s observations on the larvae of the African 
fly which come out of the earthen floor at night to feed upon 
the natives sleeping on the bare ground, he concludes: ‘‘This 
periodicity is the result of thermic sensibility. This rhythm not 
only is acquired in the course of the larval existence, but is 
changeable at the will of the experimenter.’’ These and other 
conclusions drawn for the most part from inadequate observa- 
tions, are obviously self-contradictory. 

But this condition of chaos in the literature regarding 
rhythmic periodicity serves to bring to light a significant point 
in this new field of study. It is evident that this comparatively 
new term, rhythmic periodicity, has caught the ear of many in- 
vestigators, and intrigued them to either attempt to explain the 
phenomenon without defining it, or more often, to apply the 
fascinating term, as though it were a final explanation, to any 
regularly recurring action discovered in their material. Thus 
in the above instance, the action of the African fly larvae in 
coming out at night to feed upon the natives when they lie 
down on the ground is ponderously explained ; ‘‘This periodicity 
is the result of thermic sensibility,’’ although a few lines fur- 
ther on the author naively explains that the creature’s ‘‘rhythm 
is changeable at the will of the experimenter.’’ To call this 
action ‘‘rhythmie periodicity,’’ when the creature merely turns 
to its food supply when the latter intermittently comes near, 
is obviously far-fetched. Many phenomena explained by various 
authors as ‘‘rhythmic periodicity’’ are merely adaptations or 
even temporary adjustments to a regularly recurring feature 
of the environment. The clover spreads its leaves to the sun 
during the day to make its growth; the rabbit slips out to 
nibble the clover at night so he may escape the hawk; the owl 
sleeps during the day so he may come out and get the rabbit. 
All of these actions, taken separately, have been attributed to 
rhythmic periodicity, yet not one of them would continue its 
action rhythmically (by the clock) at all if the object of its 
quest changed habit. Of course these adjustments to environ- 
ment or fellow-creatures entail morphological modifications in 
the organism—the eyes of the owl, the eyes of the hawk, ete., 
but whether the habits have caused structural variations, or 
whether morphological changes have induced new habits is a 
problem that is outside the scope of this paper. Pursuing a 


220 Trans. Acad. Sci. of St. Louis 


little further the example given above, the night and day tem- 
perature of the owl has already been cited as an example of the 
action of rhythmic priodicity. Most birds are slightly warmer 
during the day than at night, but the owl’s temperature rises 
during its nocturnal time of activity. In most cases the observer 
neither asks nor answers the question of which is the causal and 
which the resultant character; but, fortunately, in this case 
Elton makes his data significant by telling us that the tempera- 
ture variation of the owl may be reversed by reversing its 
periods of activity and rest. 

Our search for authoritative rhythms, rhythms which dictate 
terms to the organism, continues. The sleep of birds seems 
rhythmic; a rooster makes an excellent alarm-clock, provided 
you are willing to be called at four in the summer and six in 
the winter and allow him an extra crow after a midday eclipse. 
Probably one of the most persistent rhythms we can cite is that 
of the menstrual interval in mammals, yet climate, environment, 
disease and even occupation break the measure of that rhythm. 

But despite the fact that our experiments on these three moths 
show that light of a certain quality is the controlling factor for 
activity, and the habitual or rhythmic program of these crea- 
tures may be caused to vary by manipulation of the light, yet 
we must acknowledge the presence of some undiscovered con- 
trolling factor, or else something ingrained in the organism that 
makes them respond in the open at the period when they do. 
The unanswered question which still baffles us is this: If light 
rays of a certain intensity were the sole cause, why do the moths 
not flock to the females when the sun is at an equal distance 
below the horizon in the west (evening) instead of the east 
(dawn)? It may be that the physicist will be able to tell us 
that the light of dawn comprises rays which are different in 
kind from the rays of numerous artificial lights of the city. It is 
quite possible that the visual organs of these creatures are 
adapted to receive the violet rays or something akin, which our 
eyes do not perceive, and which are not present in the artificial 
lights, but I can hardly imagine that the physicist can tell us 
of differences in the rays of light shooting out from the sun an 
hour below the horizon in the west and an hour before appear- 
ing in the east. We may, with equal fitness, apply this same 
question to the activities of the day-fiying prometheas, which fly 
only in the late afternoon. 


Summary and Discussion 221 


Thus the powers and limits of rhythmic periodicity are ex- 
ceedingly difficult to define. That such a condition exists, that 
these actions occur regularly in nature, we shall not for a mo- 
ment deny. Yet we find that most of these rhythms are modi- 
fied by changes in related conditions, either within or without 
the organism. Of course, we ultimately arrive at the realization 
that the rhythmic periodicity of any organism is only that crea- 
ture’s share in the ‘‘Harmony of the Universe’’; so long as the 
planets swing in rhythm, with regular seasonal and day-and- 
night changes on our earth, all living matter must of necessity 
move in harmony with these (or other resulting) cycles. Hence 
many kinds of behavior are explained as rhythms, which are 
only adaptations to the rhythm of the whole. Only a small 
beginning has been made thus far in the study of this fascinat- 
ing subject. It can probably never be singled out alone, for it 
is inextricably intertwined with adaptation, habit, sleep, fatigue, 
stimulations, psychogenesis, ete. 

The results of the present study regarding rhythmic period- 
icity are two-fold. First, our findings agree with Davenport’s 
interpretation of earlier experiments when he says that noc- 
turnal moths are so constructed that they react only to feeble 
luminous intensity, whereas diurnal lepidoptera react to rays of 
high intensity. The second is that rhythmic periodicity within 
the organism can rarely be regarded as a causal factor or phe- 
nomenon, but only as relational, showing the interdependence of 
creatures or a creature and its environment. It is usually no 
more than a ecreature’s habitual adjustment to its surroundings, 
but there are no doubt many instances wherein rhythmic action 
is truly an innate character of the tissue, as the pulsations of the 
heart-tissue of the early chick embryo. At the present moment I 
am inclined to say that those actions which require a stimulus to 
start them are only reactions, or adaptations in behavior, while 
those actions which require outside interference to stop them 
or modify them may be truly termed rhythms. 


List of Officers, 1931 


President 
Atrrep F. SarrertHwait, U. S. Entomological Laboratory 


First Vice-President 
Water E. McCourt, Washington University 


Second Vice-President 
Joun J. Licuter, Chemical Building 


Treasurer 


James D. Ropertson, Security Building 


Recording Secretary 
ALEXANDER S. Lanesporr, Washington University 


_ Corresponding Secretary 
James I. SHANNON, Saint Louis University 
Librarian é 


ALBERT Kuntz, Saint Louis University 


Directors 


: -Lestre Dana, 1 Brentmoor Place 
. H, E. Wiepemany, Chemical Building 


Curators 
_ Josepx Grinpon, Lister Building 
Puit Rav, Kirkwood Ee 
“Gronce & Ten Missouri Botanical ee 


PLATE I 


Plate 
Nes 


I (Frontispiece). The Prairie Horned Lark Reviews Her 
tlings, 


Transactions of the Academy of Science of 


een, 
St. Louis 


VOLUME XXVII 


THE PRAIRIE HORNED LARK 


Gayle B. Pickwell 


Issued August, 1931 


THE PRAIRIE HORNED LARK 
By 
GAYLE B. PICKWELL 


- THE PRAIRIE HORNED LARK 


By Gayle B. Pickwell 


CONTENTS 
PAGE 
Introduction 1-2 
The bird 1 
The problem 1 
Acknowledgments 2 
History of the Prairie Horned Lark 3-23 
General 3 
Extension of range. 5 
Primitive range 21 
Migration 93-28 
Genera 93 
Summary of general migration 26 
Migration of sexes and individuals... oes: BO 
ummary of migration of sexes and fediviiunia, 28 
The Lark in autumn and in winter 29-34 
Flocking 29 
Habitats 29 
Associates 30 
Nightly quarters 31 
Food as ae 
Call notes col Be 
lights : 33 
Reproduction 34-113 
Breeding habitats 34-37 
General .. B4 
At Evanston, Il = 8 
At Ithaca, N. Y 37 
Song 38-49 
Sas f song. 38 
Monthly variation in song 38 
Variations in a nesting p period saeiass 


Variations throughout a . day 
The relation of the song of the Prairie ‘Horned eo 


Lark to that of other birds igae comin 
Descriptions of the SOQ n-ne . 


song... Coenen 
Quantitative studies of s Fite 
Height of the Lark in "fight song SLE eee 
Visibility of Lark in flight song 47 
Duration of flight songs... 
Number of songs per minute ‘during ‘the flight. 48 
Relation of singing male to incubating female... 48 
Summary of song... 49 


ee ee 


Molt 


The nesti 


ritories 50-55 


ser Sing Tl 50 
At Ithaca, N. Y 50 
a of ‘esting territories in subsequent nest- a 
Feeding j in felation to nesting territories. 55 
Summary of nesting territories 5d 

Courtship 55-58 
Fightin 


ng 56 
oe a of male and female Larks to each see? - 


Season of nesting 

Explanation of March n ni a 

Weather control of eek and April nests 62 

On ing nests, and the reactions of nest-building 
and egg-laying Te 68 


Nest building ee f 
Seasonal variations in nest Structure een 73 
‘*Pavings”’ nts! | 
Rete A a . 80 
Pe PN 84 
Reactions of female and male Larks during incuba- 
tion period . a 
The young 91-113 
ccpmionin,, Be ee ee tees oe 91 
Feedings . ca BO 
Food of Nestlings. . 96 


Reactions of adult Larks with young in the nest... 97 
SOG LRN ag a 98 


irae oe reactions of young...____._____-. 98 
Wide OE" FOUN 5 99 
Description of young at various ages a 
Cowbird nd bate oe 106 
Protection ... 2 308 
Nest leaving Ener 112 
eee Biot BO 


Ecology of ‘the nesting site of the Prairie Horned 


Lark in 
relation to other breeding birds, at Evanston, Ill.......113-122 


Non-breeding birds of the territory oceupied by the Prairie 
Horned Lark, at Evanston, Ill 122-127 
OMA 128-145 
elemon oe 
Ribograrhy ss 146-153 
ex 54 


INTRODUCTION 


The Bird. —Out at the bleak end of that ecological series of 
bird habitats, that begins with the heavy forests and ends with 
the barrens, lives America’s only Lark, Otocoris alpestris 
(Linn.). In that region extending from the Missouri to the 
Atlantic and from Kansas to Ontario the particular form of 
this Lark is Otocoris alpestris praticola Hensh., the Prairie 
Horned Lark. Far from the treeless Arctics, far from the 
deserts, Otocoris alpestris praticola finds as his barrens the 
plowed fields of the Midwest, the tree-denuded, wind-swept hill 
tops of the Northeastern States, those peculiarly unnatural and 
artificial barrens, the hazards of modern-day golf courses. 

If for no other reason than that here is a bird nesting where 
no bird has a right to nest; a bird in a niche that demands not 
vegetation but lack of it; a bird alone and unique in its nesting 
site without a competitor and far out at the end of the series— 
if for no other reason than this purely ecological one the Prairie 
Horned Lark invites close study. But if we add to this the 
fact that it is a Lark, a representative of our only Lark, with the 
song of a Lark, the ways of a Lark and many a habit and 
idiosynerasy peculiarly its own, then this account has its full 
excuse for being, needs no apology. 

The Problem.—Desultory observations of the Prairie Horned 
Lark were begun many years ago in eastern Nebraska where 
the writer was born. Recollections of winter rabbit hunting 
carry also associations of Larks on the wind-cleaned pastures 
and great fields of fall plowing. Their nests were found on 
the ridges of listed corn and an observation of a song still 
remains clear and trenchant. We were shocking wheat. (hence 
mid-July) when a Lark was seen climbing the air for his song. 
We watched him against the vivid sky during his long min- 
utes aloft; were amazed by that final headlong drop to earth. 

The intense work upon the observations for this paper was 
begun in June, 1925, at Evanston, Ill, continued there until 
the fall of 1926, transferred to Cornell University in the fall of 
1926, and continued at the latter place until late summer 1927. 
Twenty-six nests were located at Evanston, twenty-three of 
which were visited daily from the time of their discovery until 

1 


2 Trans. Acad, Sci. of St. Louis 


they ceased to be occupied. Seven occupied nests were found 
in Ithaca, N. Y., and their history recorded as at Evanston. 

Trips were made on two hundred and twenty-three days to 
observe the Larks and on many of these days the breeding 
grounds were visited twice. These visits were distributed by 
months, as follows: Six in January, fourteen in February, 
twenty-five in March, forty-six in April, forty-four in May, 
fifty-two in June, twenty-one in July, one in August, two 
in September, three in October, five in November, four in 
December. 

Though efforts were made to cover all activities of the Prairie 
Horned Lark, yet as data accumulated there accumulated also 
desiderata almost as large. So that, as the problem is now 
brought to an arbitrary close, the things yet to be learned seem 
more momentous by far than the few things learned—so inade- 
quate are two years of work, no matter how intensive. 

Acknowledgments,—Daily visits to an area five miles from 
the Campus of Northwestern University where the writer was 
teaching would not have been possible except for the hearty 
co-operation of the members and assistants of the Department 
of Zoology there. Sincere thanks are extended here also to 

r. P. A. Taverner of the National Museum of Canada, to 
Mr. H. F. Lewis and Mr. R. W. Tufts, Federal Migratory Bird 
Officers of Quebee and the Maritime Provinces respectively, for 
information relative to 0. a. alpestris and O. a. praticola of 
various regions of eastern Canada. To Clarice Pickwell much 
eredit is due for assistance throughout the entire period of 
preparation of the manuscript. Lastly the writer is greatly 
indebted to Dr. A. A. Allen of the Laboratory of Ornithology 
of Cornell University for the opportunity he gave that the work 
might be brought to a successful conclusion and for his advice 
on many phases of the problem. 


HISTORY 


General—The Prairie Horned Lark was described as a sep- 
arate subspecies by Henshaw (1884, p. 263). Prior to that 
time all accounts of eastern writers are concerned with the 
“Shore Lark’’, or ‘‘Horned Lark’’, which was, most likely, 
Otocoris alpestris alpestris since praticola did not, apparently, 
penetrate to the eastern states until the later part of the 19th 
century. 

The Horned Lark was described by Linnaeus (1758) as 
Alauda alpestris based upon the Alauda gutture flavo of Catesby 
(1731), whose figure of the bird is that of the northern form and 
not of praticola as Oberholser (1902, p. 809) has shown. 
Wilson’s Alauda cornuta (1808, p. 87) was also what is now 
known as Otocoris alpestris alpestris (as witness his description : 
“‘Forehead, throat, sides of neck, and line over the eye is of a 
delicate straw or Naples yellow . . . .’”) and Audubon’s account, 
from notes made in Labrador, was of this bird in its home. 

Since, then, most early writers are concerned with a sub- 
Species other than the Prairie Horned Lark, their accounts will 
be but briefly summarized here. Wilson (1834) says of the 
Horned Lark: “There is a singular appearance in this bird, 
which I have never seen taken notice of by former writers, viz., 
certain long black feathers, which extend by equal distances 
beyond each other, above the eyebrow; these are longer, more 
pointed, and of a different texture from the rest around them; 
and the bird possesses the power of erecting them, so as to 
appear like some of the owl tribe. Having kept one of these 
birds alive for some time, I was much amused at this odd 
appearance, and think it might furnish a very suitable specific 
appellation, viz., Alauda Cornuta, or Horned Lark.’ —— 
he says: “I have never heard of their nest being found within 
the territory of the United States.” 

Audubon (1834) knew more than just the littoral bird of the 
Atlantic Seaboard for he journeyed to Labrador and found 
the Lark at home. His vivid description was the basis for all 
subsequent accounts of the Horned Lark for fifty years and 
little was added between the time of his writing and 1875. He 


says, in part: “The face of the country [Labrador] appear 
3 


4 Trans. Acad. Sci. of St. Louis 


as if formed of one undulating expanse of dark granite, cov- 
ered with mosses and lichens, varying in size and color, some 
green, others as white as snow, and others again of every tint, 
and disposed in large patches or tufts. It is on the latter that 
the lark places her nest, which is disposed with so much care, 
while the moss so resembles the bird in hue, that unless you 
almost tread upon her as she sits, she seems to feel secure, and 
remains unmoved. Should you, however, approach so near, 
she flutters away, feigning lameness so cunningly, that none 
but one accustomed to the sight can refrain from pursuing her. 
The male immediately joins her in mimic wretchedness, utter- 
ing a note so soft and plaintive, that it requires a strong 
stimulus to force the naturalist to rob the poor birds of their 
treasure. 

“The nest around is imbedded in the moss to its edges, which 
is composed of fine grasses, circularly disposed, and forming a 
bed about two inches thick, with a lining of grous’ feathers, 
and those of other birds. In the beginning of July the eggs 
are deposited. They are four or five in number, large, greyish, 
and covered with numerous pale blue and brown spots. The 
young leave the nest before they are able to fly, and follow 
their parents over the moss, where they are fed for about a 
week. They run nimbly, emit a soft peep, and squat closely 
at the first appearance of danger. If pursued, they open their 
wings to aid them in their escape, and separating, make off 
with great celerity. On such occasions it is difficult to secure 
more than one of them, unless several persons be present, when 
each can pursue a bird. The parents all this time are following 
the enemy overhead, lamenting the danger to which their 
young are exposed. In several instances the old bird followed 
almost to our boat, alighting occasionally on a projecting crag 
befor =e, and entreating us, as it were, to restore its offspring.” 

Swainson and Richardson (1831) did not add to this account. 
Samuels (1887) and Baird, Brewer and Ridgway (1875) quote 
Audubon though the latter add that Nutall ‘‘started a Shore 
Lark from her nest on the banks of the Platte. It was in a 
small depression on the ground and was made of bent grass and 
lined with coarse bison hair’’, (undoubtedly 0. a. praticola or 
0. a. leucolema). Nutall (1832) himself gives an account very 
similar to that of Wilson. In an earlier edition, Baird, Brewer 


History 5 


and Ridgway (1874) in speaking of the Horned Larks say: 
“‘starting with North America north of the United States we 
begin with a style absolutely indistinguishable from that of 
Europe, this, to which the name cornuta belongs, visits the 
Eastern States only in winter, but breeds over the prairie region 
of Wisconsin, Illinois and westward.’’ These authors believed 
thus that cornuta included also what came to be praticola, though 
they remark at the peculiar breeding distribution. 

The first suggestion that the Horned Lark breeding east of 
the Mississippi is not the same as OQ. a. alpestris of the Atlantic 
coast came from Allen and Brewster (1882) who suggested that 
it is nearer Leucolaema Coues than the former. Two years later 
Henshaw (1884) erected the subspecies Otocoris alpestris prati- 
cola and gave as the range the upper Mississippi Valley and 
region of the Great Lakes. 

Extension of Range—Partly as a result of the stimulus that 
followed the erection of a new subspecies in one of the most 
thoroughly worked ornithological regions and partly due to an 
actual extension of range of O. a. praticola, there appeared forth- 
with an extensive list of published notes of the occurrence of 
this form where previously it had not been thought to exist or 
had not been separated as distinct from O. a. alpestris. 

However a few years prior to the distinction of the Prairie 
Horned Lark as a separate subspecies there are two or three 
references to a Horned Lark breeding in New York and Ontario 
that was, undoubtedly, this subspecies though not at the time 
recognized as differing from O. a. alpestris. The earliest of these 
appears to be that of McIlwraith to whom Coues (1874) refers 
as giving information of Larks breeding about Hamilton, Canada 
West (western end of Lake Ontario). The earliest publication 
by Mcllwraith in this regard that has been located is that of 
his 1883 ‘Bird Notes from Western Canada”’: ‘Getting out- 
side of the city we at once lost sight of Passer domesticus, who 
has not yet betaken himself to the farm houses, but almost 
immediately met with another recent addition to our birds which 
promises ere long to be as abundant in the country as the Spar- 
row is in the city. This is Eremophila alpestris, Shore Lark. 
When I first made the acquaintance of this species twenty years 
ago [italics mine], the few individuals observed came and went 
with the snowbirds, and kept along with them while here. They 


6 Trans. Acad. Sci. of St. Louis 


were stout, well-developed birds, with the black and yellow 
markings clear and decided. Some ten or twelve years since 
[italies mine] a new race made its appearance, smaller in size, 
the colours paler and having altogether a bleached, washed-out 
look about them when compared with the others. These have 
remained permanently and increased from year to year, have 
now become our most common winter resident in the country. 
They breed very early by the roadsides and in the low commons 
everywhere, and at this season of the year are seen running in 
the road tracks or sitting in rows of fifteen to twenty along the 
fences waiting till you pass that they may return to their regu- 
lar feeding ground’’. 

The above account is of great importance for several reasons. 
First, MelIlwraith’s “stout, well-developed birds, with black and 
yellow markings clear and decided . . . that came and went 
with the Snowbirds’’ were, beyond question, Otocoris alpestris 
alpestris seen by him on their migrations to and from their north- 
ern breeding grounds. His ‘‘new race’’, ‘‘smaller’’, with ‘‘colours 
paler’’, that ‘‘remained permanently’’ was, as assuredly, what 
came to be Otocoris alpestris praticola, the Prairie Horned Lark. 
Secondly, critics of the supposed eastward movement of the 
Prairie Horned Lark (for which see further) cannot impute 
that these records are the results of a new interest and more 
careful observations which might possibly have accounted for 
many of the records made after publication of Henshaws’ 
(1884) paper on the Horned Larks. Thirdly, here is an unques- 
tioned date of the Prairie Horned Lark’s first appearance in 
Ontario, viz., “ten to twelve years” prior to 1883, that is, 1871 
to 1873. In 1894 Mellwraith, writing again of the “Birds of 
Ontario”, says of this Horned Lark: “So far as I can remember, 
this species first appeared in Ontario about 1868.” 

The first New York record of a breeding Lark was that of 
the Rev. Wm. Elgin, who, as reported by Langille (1892), 
found a nest at Buffalo April 28, 1875. Merriam (1878, p. 53) 
in his ‘“‘Remarks on Some of the Birds of Lewis County, North- 
ern New York” quotes A. J. Dayan, who, in turn, quotes Dr. 
C. P. Kirley of Lowville as follows: ‘‘I first observed Eremo- 
phila alpestris July 16, 1876, when I shot one two-thirds grown 
and saw the parents. In the same locality June 24, 1876, I 
noticed a pair of old birds, and on searching for their nest, I 


History 7 


found it not more than eighteen inches from the main road. 
It contained three unfledged young. Since then I have both 
seen and taken it during the breeding season.” Again Merriam 
(1878, p. 54) in reviewing Rathbun’s “Complete List of Birds 
of Cayuga, Seneca and Wayne Counties’’ published in the 
Auburn Daily Advertiser, August 14, 1877, draws attention to 
the statement that Eremophila alpestris is ‘‘resident and toler- 
ably common in winter . . . a few breed.’’ Howey (1878, 
p. 40) at Canandaigua, N. Y., saw the ‘‘Shore Lark’’ (Zremo- 
phila alpestris) with a worm in the bill, May 29, 1876, ‘‘fly into 
a meadow”. On June 11, found “an old bird with three young 
ones in a highway”. 

Merriam’s (1878, pp. 54-55) comments on the above records 
are, in the light of later knowledge of the Prairie Horned Lark, 
of interest. Says he: “Mr, Dayan’s note (on the authority of 
Dr. C. P. Kirley) is particularly interesting as it extends the 
known breeding range of the species (Eremophila alpestris), 
within the United States, eastward to the western border of the 
Adirondack wilderness, beyond which it must pass to the 
northward (through Saint Lawrence County) into Canada, and 
thence to Labrador. Whether it has for many years bred 
within the limits of the State of New York, or has recently 
extended its breeding range, as seems to be the case with the 
Lark Finch (Chondestes grammaca) and some other species, 
remains to be decided; I incline to the latter view. It breeds 
about Hamilton, Canada West (MclIlwraith) and abundantly 
along the Labrador coast (Audubon and Coues)’’. 

Thus Merriam, after reference to Coues’ (1874, p. 38) re- 
striction of all Horned Larks (except Eremophila alpestris 
‘‘breeding northerly’’) to Iowa and Minnesota westward, eon- 
cludes that the New York forms were of the northern subspecies, 
had extended their range from Labrador south and west! 
Whereas, as will be shown later, the reverse proved to be the 
case. Those birds ‘‘on the dry interior plains from Iowa and 
Minnesota westward’’ (Coues, 1874, p. 38) had extended their 
range east and north! 

Further records of a breeding Lark in New York, that was 
undoubtedly praticola though published before that subspecies 
was erected, are as follows: Davis (1878) tells of a nest of 
“‘Eremophila cornuta’’ found at Utiea, N. Y., April 15, [year ?]. 


8 Trans. Acad. Sci. of St. Louis 


Lattin (1881) reports ‘‘Eremophila alpestris’’ quite common in 
Orleans County, N. Y., and on April 17, 1880, found a nest in 
an old pasture at Gaines. Later (May 28) another in a straw- 
berry patch and June 15 (circa) yet another in a tobacco patch. 
Merriam (1881, p. 231) in his “Preliminary List of Birds Ascer- 
tained to Occur in the Adirondack Region, Northeastern New 
York’’, says of ‘‘Eremophila alpestris’’, Shore Lark: ‘‘ Rare, but 
becoming common. Breeds on the sandy fields along the west- 
ern border of the wilderness and probably at other localities.” 
Park (1881), tells of young Horned Larks taken at Green 
Island, N. Y., April 22, 1881 (junction of Mohawk and Hud- 
son). An adult pair was similarly taken April 29, 1881. Seven 
years later Park (1888) records the fact that Wm. Brewster 
identified these as Otocoris alpestris praticola. At the same 
time he mentions the taking of O. a. praticola at Troy, N. Y., 
February 22, 1883, and March and October, 1887. 

Following the publication of Henshaw’s (1884) paper on the 
Horned Larks, records of the Prairie Horned Lark are numer- 
ous and present a steady east and northward movement, 
followed later by a southward invasion. This can best be pre- 
sented by states. 

New York. Langille’s, Howe’s, Davis’, Lattin’s and Rath- 
bun’s accounts (see above) have already been given as show- 
ing the presence of the breeding praticola in the Adirondack 
region, Cayuga, Seneca, Orleans and Wayne counties and in 
Canandaigua, Utica and Buffalo, N. Y. (northeastern, central 
and western portions of the state), in 1875-1881. Park had 
breeding forms from Green Island and Troy (east-central bor- 
der) in 1881-1887. Davison (1885, pp. 217, 218) secured the 
first nest and eggs of praticola (‘‘Eremophila alpestris”) from 
Niagara County (extreme western county), on June 17, 1884. 
The nest was in the side of a manure heap in the field. The 
young farmer who located it for him said it bred there three 
times a year for there were “young birds in April, June and 
August’’. Dutcher (1888) records O. a. proaticola as taken on 
Long Island, Queen County, July 31, 1888; another, a young 
bird, was taken September 14, 1887. 

Vermont. The earliest records of the presence of the Prairie 
Horned Lark in New England and of its breeding there seem 
to be those of Parkhill (1889). He tells of nests, presumably 


History 9 


of this species, in April, 1885 (three young, one egg), another 
in April with four eggs; a female with a nearly-formed egg 
was taken April 6, 1888. A positive record was made April 
19, 1889, at which time the female was taken from the nest and 
later identified by Brewster. These records were at Cornwall. 
Several years later Howell (1901), records that it was first 
noticed in Stowe Valley, Vermont, in 1898; bred there in 1901. 

Massachusetts. The first Horned Larks taken in Massachu- 
setts that may have been O. a. praticola were secured by 
Brewster at Concord, in July, 1869. These are referred to by 
Howe and Allen (1901) as being recorded in Brewster’s: 
“Minot’s Land and Game Birds,” second edition, 1895, p. 247. 
This latter reference has not been available to the writer, but 
it is most probable that it is this record that Coues (1874) 
cites from Maynard’s Guide (1870, p. 121) and adds “perhaps 
breeding’’. Brewster (1888), after the erection of O. a. prati- 
cola, went over his collection and found a pair of Prairie Horned 
Larks that had been taken February 28, 1883, at Revere Beach, 
Massachusetts. This seems to have been the earliest definite 
record for the subspecies in the state. Intrigued by this Feb- 
ruary, 1888, discovery he shot twenty-three Horned Larks the 
next winter, December 15, 1888, at Great Island, near Hyannis, 
Massachusetts, and found two of praticola in the lot (1889). 
Faxon (1892) took birds in the breeding season at North 
Adams, and Williamstown, Massachusetts, in 1890 and 1891. 
Brewster, having collected the first for the state, had the pleas- 
ure of recording the first bona-fide nesting (1894), when Henry 
R. Buck reported a nest found by Buckingham with a set of 
fresh eggs at Pittsfield, Massachusetts, July 10, 1892. Other 
records of breeding followed this, the latest of significance 
being that of Townsend (1904), who records adults and young 
collected at Ipswich, Massachusetts, August 11 and 13, 1903. 
These and that of Forbush (1927), who shows a breeding local- 
ity on Cape Cod, place the Prairie Horned Lark at the sea. 

New Hampshire. Faxon (1892), records the first breeding 
for this state at Franconia with records of capture of adults 
and second brood young of June 4 and July 21. Torrey (1905), 
says that it was found breeding on Mount Washington above 
the tree line, July 7-19, 1905. 

Maine. Knight (1897), by requesting collectors to send to 


10 Trans. Acad. Sci. of St. Louis 


him their Larks for examination, found the following to be 
praticola: Pittsfield, Somerset County, March 29, 1892, male; 
March 27, 1893, male; March 22, 1894, female; Bucksport, 
Hancock County, 1886 or 1887, two; Bangor, March 30, 1887, 
male; North Bridgton, Cumberland County, March 13, 1897, 
four; Lewiston, February 26, 1897, one. At that time the bird 
had not yet reached the Maine coast, nor was there evidence of 
its breeding within the state. Swain (1900) collected a female 
and young July 17, 1900, between Waterville and Pishon’s 
Ferry on the east side of the Kennebec and so established the 
first breeding record for the state. 

Connecticut. Woodruff (1905, p. 420) found it breeding at 
Litchfield, May 25, 1905, and Judd (1908, p. 129) found it 
breeding in Danbury. 

The northward movement of the Prairie Horned Lark into 
northeastern Canada has been very slow and of much later 
date (excepting Ontario) than that into New York and south- 
ern New England. The bird must have reached these parts 
from New York and New England. However, because of this 
contiguity, the provinces will next be considered. 

Ontario. It is probable, judging from its geographical posi- 
tion and the early date of the appearance of the Prairie Horned 
Lark there, that Ontario received its birds from Michigan and, 
secondarily, gave an ingress to New York and regions further 
east. MclIlwraith (see above) noted that the Prairie Horned 
Lark first reached Hamilton (at west end of Lake Ontario) 
between 1871 and 1873 (or 1868 as he later avers). Fleming 
(1901) writes that this Lark appeared first at Port Sydney in 
1887 and is an abundant breeding resident. Again Fleming 
(1907) lists it as a common breeding resident of Toronto. 
Finally, Soper (1923, p. 501) calls it a common summer resident 
of Wellington and Waterloo counties. 

bec. The Prairie Horned Lark did not, apparently, pene- 
trate to this province until long after it entered Ontario. 
Indeed, it seems probable that it finally entered this region by 
way of northern New York and Vermont rather than from the 
west. Dionne (1906) does not mention it as a breeding bird, 
but Terrill (1911) quotes Wintie s 1896 “List of Montreal 
Birds” as mee this Lark as a “summer resident; common”. 
Terrill adds: “This species has been steadily on the inerease 


History 11 


[since 1896] and I should call it an abundant summer resident.” 
Another recent record for the southern border of Quebec is 
that of Mouseley (1916), who found the Prairie Horned Lark 
breeding at Hatley, Stanstead County, for the first time in 
April, 1915, 

The Larks of Quebec nesting north of the Saint Lawrence 
River seem to be Otocoris alpestris alpestris (Lewis, 1921). 
And Townsend (1923) has recently shown that this form breeds 
south of the Saint Lawrence Bay on the Gaspe Peninsula. 
Mr. P. A. Taverner, in a letter to the writer dated June 2, 1927, 
gives the following information relative to the birds of the 
North Shore of the Gulf of Saint Lawrence and the Magdalen 
Islands: ‘‘Praticola has been generally assumed to be the Mag- 
dalen Island bird, but we have well-marked alpestris (appar- 
ently breeding), along with others from there that agree as 
well with hoyti as with praticola. Of course an intermediate 
between praticola and alpestris, carrying the colors of the for- 
mer and the size of the latter might well be indistinguishable 
from hoyti and probably that is what these birds are. If a deci- 
Sion is necessary it is best perhaps to say that the birds of the 
Magdalens and the North shore of the Gulf of the St. Lawrence 
are O. a. praticola intergrading with O. a. alpestris. 

New Brunswick, Moore (1903) gives the most extensive 
account of the first occurrence in this province. He says: “It 
has been known for some years that Prairie Horned Larks bred 
in New Brunswick as several times the old birds had been 
observed feeding the young.” The first nest was found spring 
of 1902. It contained four eggs. He gives the following addi- 
tional material: On Mount Keswick, May 26, 1898, a pair was 
observed with actions of breeding birds. On July 9, 1895, an 
adult Lark was noted feeding two young. a 

Prince Edward Island. Klugh (1921) noted the Prairie 
Horned Lark as ‘‘common in the fields’’. 

Nova Scotia. Mr. R. W. Tufts, Federal Migratory Bird 
Officer of the Maritime Provinces, who established the first breed- 
ing record for Nova Scotia, has, most kindly, supplied me with 
information regarding the status of the Prairie Horned Lark 
in this province and others under his jurisdiction. Because of 
the value of this communication it will be quoted in full: 

‘On September 2, 1918, two Prairie Horned Larks were seen 


12 Trans. Acad. Sci. of St. Louis 


feeding in the road near Aylesford, Kings County, Nova Scotia. 
One of these was taken and sent to Mr. Piers, Curator of the 
Provincial Museum at Halifax. My notes give the following 
measurements: L. 7.25’, Wing 3.92’, Tarsus 2.80’, B. from N. .36’. 
The bird was mounted and is still in the Provincial Museum and 
constitutes the first record for Nova Scotia. I regret that my 
notes do not state whether the specimen was male or female. 

‘The following subsequent records may be of interest: 1920, 
May 19th, one seen on the road to Yarmouth County, Nova 
Scotia. August 30th, three seen flying over the sandy barrens 
known as ‘‘Old Aldershot’? between Auburn and Kingston, 
Kings County. 1922, May 20th, one seen at ‘‘Old Aldershot”’ 
near Auburn. June, reported by a reliable observer as breeding 
in the fields and pastures at Amherst, Cumberland County, 
Nova Scotia, a nest with eggs being reported. 1925, May 7th, 
saw male and female on plains at ‘‘Old Aldershot’’ which were 
unquestionably mated. 

‘T find in my files a letter dated June 22, 1921, from a reliable 
correspondent and observer (Mr. Alban Brown), living in Pictou 
County, Nova Scotia, which states that Prairie Horned Larks 
were common about his farm and adjacent fields, during the 
summer of 1920 until the fall of that year and ‘this year (1921), 
they appeared the last of April while I was harrowing, and from 
their actions I am sure that they were preparing to nest.’ Mr. 
Brown wrote me again on August 21, 1921, stating that two or 
three young Prairie Horned Larks were seen on his farm, one 
of which was able to fly only a short distance and was finally 
captured for examination and identification. 

“‘A letter received from this correspondent a few weeks ago 
tells that this species has been observed continuously in Pictou 
County every year since, but does not appear to be increasing. 

“It is my opinion that Prairie Horned Larks are now fairly 
well established as summer residents throughout Nova Scotia in 
localities which are suitable to their habits, though in no place 
are they abundant or even common. 

“During the last four or five years I have had opportunity 
to cover New Brunswick frequently during the summer months, 
traveling by motor, and am therefore able to give you first 
hand data concerning the distribution of the species in ques- 
tion in that provinee. They are to be found along the north 


History 13 


shore in Westmoreland, Kent, Northumberland, Gloucester 
and Restigouche Counties, and have been noted in sections 
near the coast, but I have not seen them in any other counties 
in the province, but would expect to find them in Charlotte 
and Saint John Counties as well. I have just returned from 
a trip along the north shore in the counties first named, and 
saw in all only five specimens, two of these were taken in 
Westmoreland County, a male and a female, and dissection 
proved that they were mated birds. 

“Within the past three or four years I have, on a number 
of occasions, observed Prairie Horned Larks throughout the 
rural districts of Prince Edward Island and they are unques- 
tionably breeders in that province. I regret that I am not 
able to give you exact dates of the observations in Prince 
Edward Island.” 

Practically contemporaneous with the movement of the 
Prairie Horned Lark into New England as a breeding bird, 
appear records of its occurence in Pennsylvania; later it 
appeared in Maryland, and still later in West Virginia. If, 
as the records show, the Lark first appeared in Ontario, then 
in northern and western New York and from New York to 
New England, it is not unreasonable to suppose that New 
York also provided an ingress to Pennsylvania and the regions 
east of the Allegheny mountains. 

Pennsylvania. The first record for the state is at Erie, on 
the lake of that name, only a few miles west of the southwest 
border of New York. It was reported by Sennett (1889). Todd 
(1891) reported this Lark in Butler County, June 10, 1889, 
and ‘‘probably breeding.’’ Dwight (1892) shot a specimen 
of O. a. praticola at Athens, Bradford County, June 12, 1891 
(the northeast region of the state). Bailey (1896) reported it 
as a common breeder in northern Elk County (north central 
region). Rhoads (1899) recorded it as breeding in a suburb 
of Pittsburgh in 1898, also in Allegheny, Beaver and Butler 
Counties. It is interesting to note that Brooks (1908) found 
a Lark breeding in Pittsburgh also (April 4, 1908), in Schenley 
Park* the same situation as given for the first record for the 
city eity by Rhoads ten years previously. Finally Harlow (1918) 

Schenley Park, Pittsburgh, is, it seems, a favorite place 


for ‘Praiie ag rea Lark observations for Sutton (1927) makes frequent 
reference to Lark activities noted there. 


14 Trans. Acad. Sci. of St. Louts 


states that the bird breeds over most of Pennsylvania north of 
Northampton, Schuylkill, Northumberland, Cumberland and 
Franklin Counties, was found nesting on the Pocono Plateau in 
Huntington, Center and Green Counties. 

Maryland. LHifrig (1904) reports the Prairie Horned Lark 
as breeding in the “higher parts” of western Maryland and 
again (1920) speaks of it as a “not uncommon breeder” in 
the vicinity of Oakland, western Maryland. In neither of 
these cases does he say that nests were found, though in refu- 
tation of a “first” breeding record reported by Swales (see 
below), he says (1923) that he “has taken this race summer 
and winter in Allegheny and Garrett Counties since 1900, and 
his records of breeding (see above) “were backed by speci- 
mens taken.” Swales (1922) reports an adult male and two 
juveniles taken at Laurel by Marshall. 

District of Columbia. No breeding records were uncovered, 
but Smith and Palmer (1888) took O. a. praticola in the vicinity 
of Washington in February, 1881. 

West Virginia. Brooks (1908) noted O. a. praticola m 
Kanawha County, June 19, 1902; “seems to be resident” in 
Wood County. A specimen was taken in the Poco Bottoms, 
Putnam County, October 15, 1902; a pair was secured at 
Cameron, Marshall County, June 11, 1900; noted in Lewis 
County in breeding season; in 1905, young were noted just 
from the nest near Morgantown. At French Creek, April 11, 
1905, a nest with three young birds was found. Dadisman, in 
an account in Bird Lore (1919), says that “three years ago 
this summer,” a pair of Prairie Horned Larks nested in Mor- 
gantown, West Virginia. The nest was seen. 

Thus it seems that the Prairie Horned Lark, having entered 
Ontario, 1868-1873, moved next into New York and simul- 
taneously from there into Pennsylvania on the south and New 
England on the east. Its southern breeding limit is West 
Virginia on the south, but the sea alone has stopped it from 
Massachusetts to the Saint Lawrence. 

This assumed extension of range of the Prairie Horned Lark 
has not been without its critics. The first of these is Norton 
(1906), _who asserts that Henshaw’s (1884) erection of the 
subspecies merely directed attention toward it, and so ac- 
counts for the many recent records of the Lark where formerly 


History 15 


it had not been known to breed. He further claims that Audu- 
bon, in 1833, discovered the equivalent of the Prairie Horned 
Lark at Bras d’Or, Labrador, and figured it (“Birds of Amer- 
ica” II, plate CC.), describing it as the nuptual plumage * of 
the Horned Lark in Volume 2, Ornithological Biography 
(1834), p. 575). Moreover, Norton goes on to say that the 
Prairie Horned Lark was rediscovered by the Bowdoin Col- 
lege Expedition in Labrador in 1891 (Proc. Portland Soe. Nat. 
Hist., II, p. 153). And, again, that Maynard’s “Naturalist’s 
Guide” (p. 121), published in 1870, cites a reeord of this sub- 
species for July, 1869, in eastern Massachusetts (see also above 
under Massachusetts). All of which, in Norton’s opinion, 
“shows conclusively that it has not suddenly extended its range 
eastwardly.” 

Another competent ornithologist, Barrows (1912), believes 
this “eastward movement” invalid. He says (p. 409): “It is 
conceivable that the species has always occurred in small num- 
bers throughout the northeastern states, but that it has passed 
unnoticed until recent years, when the increase in the number 
of collectors and the more general publication of field notes 
have called attention to its presence.” 

In my opinion, however, there is no question as to the valid- 
ity of this extension of range. Opportunity has not been 
presented, as yet, to look up Audubon’s illustration to which 
Norton (see above) calls attention, but O. a. praticola was elim- 
inated as a bird of Labrador in Townsend’s and Allen’s ‘‘Birds 
of Labrador’’ (Bost. Soc. Nat. Hist., V. 33, No. 7, pp. 277-428, 
July, 1907). Furthermore, the following points seem to estab- 
lish the probability of this extension of range beyond a question: 


(1) The general removal of forests throughout all the 
northeast has made available, within the last seventy-five 
years, vast areas of sterile ground admirably suited to 
the uses of the Lark. One has but to climb the hills of 
south central New York, view their rock-strewn, barren 
summits, from the soil of which nearly all virtue has long 
ago leached out, to become forcibly convinced of this 
Robert Ridgway as late as 1881 pear aeres bint gm Leg vg 


* Even Mr. 
ef praticola, which. in Illinois, to be a 
“much f la, which Be — nora ncn Fa 


16 Trans. Acad. Sci. of St. Louis 


fact. Such must also be true of much of New England, 
of Pennsylvania, Maryland and West Virginia. 

(2) Wherever agriculture or farming is practiced, 
there the Prairie Horned Lark will find suitable breeding 
quarters in the gardens, on the plowings, in the closely- 
grazed pastures. 

(3) The Prairie Horned Lark is possessed of a remark- 
able versatility in the rapid adoption of new breeding 
areas, as will be shown later in the study of the bird at 
Evanston, IIl. 

(4) The keen observation of McIlwraith (see above), 
who gives within a year the date of the appearance of a 
new Lark into Ontario in a region that he had carefully 
worked several years prior to this time, is one of the 
best evidences of the extension of range. Furthermore, 
his observations were made before Henshaw erected the 
subspecies. 

(5) The first New York records, made shortly after the 
observations of Mcllwraith, were, in some cases, in a 
region that had long been studied ornithologically. And 
these were made before the publication of Henshaw’s 
paper. 

(6) The July record of 1869 in Maynard’s Guide (see 
above), if it actually represented a breeding bird, may 
well have represented one of the early adventures of the 
Lark, a pioneer, who was followed by numerous settlers 
twenty to thirty years later. 

(7) The orderly sequence of records from Ontario to 
eastern Massachusetts, from New York to West Virginia, 
after ornithologists everywhere were on the lookout for 
Otocoris alpestris praticola, is in itself the best evidence of 
the routes undertaken. 


Forbush (1927) stoutly defends the idea of the eastward 
movement and increase of the Prairie Horned Lark. He gives 
as a probable reason for this extension “the fact that much 
of the prairie land in which it formerly bred has been settled 
and cultivated, and tree claims have been planted with trees, 
thus driving out the species from thousands of square miles 
in the aggregate (now wooded) in which it formerly bred.” 


History 17 


With this the writer cannot agree, for, in the first place, the 
Lark probably has not lessened in numbers one whit since 
man entered its original home, the prairies, but has increased, 
seizing upon cultivated fields as recompense in great measure 
for loss of the smaller denuded or short grass areas of prairie 
—the only places where it would have bred (see further). 
Also, the wooded area in this original home has nothing of 
the extensiveness that Mr. Forbush ascribes to it, consisting 
for the most part of scattered lots. Further, Forbush says, 
“On the other hand a great region in Indiana, Ohio, New 
York and New England formerly heavily timbered has been 
more or less cleared, and the fields and pastures of the East 
offer suitable breeding places and a plentiful food supply for 
this species here.” With this last the writer is in full accord; 
indeed, this is probably the most important reason for the 
northeastward movement. 

It is probable that regions other than those listed above 
have been occupied recently by the Prairie Horned Lark as 
conditions within them have become suitable. Quite certainly 
the region from Indiana to Ohio, or at least from Indiana 
through Michigan, must have provided breeding conditions 
before the bird would have entered Ontario or New York. 

Ohio. Though Jones (1903) lists O. a. praticola as common 
nearly throughout the state, yet Wheaton, in his report on 
the Birds of Ohio published in 1882, made no reference to a 
breeding Lark. Henshaw, likewise (1884), on giving the dis- 
tribution of O. a. praticola, made no reference to Ohio. Hen- 
ninger (1902) says that this Lark appeared first in middle 
southern Ohio Oct. 28, 1899. Dwight (1890) records a speci- 
men from Circleville, Ohio, which may have been the one 
Henninger mentions. If these records constitute a reasonable 
estimate of the first appearance into the state, then it is un- 
likely that Ohio was the source which supplied Pennsylvania 
and western New York. 

Allen (1878) quotes David Starr Jordan in the 
first record noted from Indiana. Says J ordan: “Professor 
Brayton shot here (near Indianapolis) this morning a number 
of Shore Larks (Eremophila alpestris) and among them were 
two young birds, about grown. The birds usually remain here 
most or all of the summer, but I never knew of their breeding 


18 Trans. Acad. Sci. of St. Louis 


so early.” These birds were taken April 24, 1878. Everman 
(1889) says of Otocoris alpestris praticola, “up to 1879, very 
rare; since then becoming more common every year, until it 
is now a common resident, most abundant, however, in winter 
and early spring.” Butler (1879) quotes Mrs. Hines as re- 
porting the Prairie Horned Lark on the increase in DeKalb 
County. He further notes that none was seen in Franklin 
County later than February until 1886, where a definite breed- 
ing record was secured in 1891. Further, he quotes Evermann 
as saying it was rare in Carroll County up to 1879, but that 
it was a common resident there in 1886. He lists the bird as 
breeding as far south as Bloomington, Spearsville, Greens- 
burg, Richmond, Brookville and Bicknell. 

Michigan. Henshaw (1884) had specimens in breeding 
plumage from this state, as did Dwight in 1890 (Cadillac, 
Mich.). Cooke (1893) gives a record of a February nest at 
Plymouth. Wood and Frothingham (1903) record O. a. prati- 
cola as breeding on the plains of Ascoda County (northern 
Michigan), and Barrows (1912) mentions records of nests in 
Otsego County in 1902; in Ingham County in 1904; Port 
Huron, Jackson County, 1889; in Grand Rapids, 1896; and 
southeastern Michigan, 1895. To presume that the Lark en- 
tered Ontario from Michigan also carries the presumption 
that it bred first in Michigan. Since Michigan was, at one 
time, extensively wooded, the present general distribution in 
the state must have followed the cutting of the timber. This 
timber-cutting should, for the sake of the hypothesis, have 
occurred some time prior to 1873, the date of the appearance 
of the Prairie Horned Lark in Ontario. However that may 
be, it is more probable that Michigan provided entrance to 
Ontario than Indiana or Ohio. 

Illinois. It is probable that the prairies of Illinois consti- 
tuted an early home of the Prairie Horned Lark and from 
here the bird spread north and east. Ridgway (1878) says of 
Eremophila alpestris, Horned Lark: “Abundant in suitable 
localities.” Henshaw (1884) and Dwight (1890) had breeding 
birds from this state. Dwight lists Mt. Carmel, Richland 
County, Adams County, Mason County, Sugar Creek Prairie, 
Waukegan, Calumet, Riverdale, W. Northfield and Evanston as 
the locations of his breeding specimens. Poling (1889) calls 


History 19 


it an “abundant breeder” at Quincey. Since much of this paper 
is concerned with the Prairie Horned Lark in northern IIli- 
nois, more will not be said of their distribution, but Forbes’ 
(1908) records of Prairie Horned Lark numbers might well be 
given here. In this statistical study A. P. Gross and H. A. 
Ray walked, thirty yards apart, across portions of southern, 
central and northern Illinois, recording the birds of a fifty- 
yard strip. They observed 296 Prairie Horned Larks, or 3.8 
per cent of the total number of birds. The Larks were sev- 
enth in order of abundance, being exceeded by Red-Winged 
Blackbirds, Dicksissels, Mourning Doves, Bronzed Grackles, 
Meadowlarks and English Sparrows. 

Similar surveys made in 1909 (Forbes and Gross, 1922), 
differed from those of 1907 in that records were made for the 
three portions of the state at nearly the same dates (that is 
in June, July and August in each), whereas in 1907 southern 
Illinois was covered in June only, central Illinois in July 
only and northern Illinois from very late July (July 29) to 
early August only. The 1909 records are thus more repre- 
sentative. In this later survey 414 Horned Larks were seen 
and they assume sixth place in rank of total number seen 
(being preceded by Mourning Dove, Cowbird, Meadowlark, 
Bronzed Grackle and English Sparrow). Indicative also of 
the Prairie Horned Lark’s breeding range is the very informa- 
tive fact that, for the two years in southern Illinois, it was 
25th in number (only 55 being recorded), in central Illinois 
it was 8th (204 birds), and in northern Illinois 5th (451 
birds). Now, since the amount of ground covered in each 
region varied less than fifty percent, these figures show id 
striking preference for northern Illinois. This may > 
clue to the optimum conditions for breeding of the Prairie 
Horned Lark. The conditions of the country, verdure and 
erops were strikingly similar in all the regions covered thus 
leading to the conclusion that general distribution in this 
state is a matter of life zone (temperature), and since south- 
ern Illinois is Lower Austral, central Illinois Upper Austral 
and northern Illinois Transitional, then the optimum for the 
Prairie Horned Lark is not reached until the temperatures of 
the Transitional zone prevail though it may breed in all three 
(and indeed on up into the Canadian). 


20 Trans. Acad. Sci. of St. Louis 


However, conditions other than general life zone restrict 
the Lark severely in its breeding habitat, more so than with 
many birds, but these will be considered under “reproduc- 
tion.” 

From Illinois it seems probable that the Lark moved into 
Indiana and Michigan, from Michigan to Ontario, from 
Ontario to New York, from New York to New England and 
Pennsylvania. It is possible that the route may have been 
by way of Ohio to western Pennsylvania, from thence to west- 
ern New York and from thence to Ontario. The records in- 
cline me to the former view however. It is obvious, that the 
route must have been through Indiana, Michigan or Ohio. 

Wisconsin. Coues (1874), tells of Larks nesting at Racine, 
Wisconsin. Kumlien and Hollister (1903), call it the “com- 
mon resident Lark, abundant breeding bird in all suitable 
localities.” There is no further evidence to show that it has 
recently occupied this state and it is probable that regions of 
prairie have been utilized as breeding grounds for a long time, 
though undoubtedly wherever it occurs in regions previously 
forested it must, of necessity, have come into them recently. 


Missouri. The prairies of northern Missouri have been the 
homes of the Prairie Horned Lark for a long period but there 
is evidence that it here has extended its range south until it 
now breeds throughout the state. One of the earliest records 
is that of Scott (1879), who notes ‘‘Eremophila alpestris” as 
a common resident. “Found only on the Prairies, breeds.” 
Woodruff (1908), gives a breeding record for Eudy, in Shan- 
non County (south central part), March 23, 1907. Widmann 
(1907), calls this Lark a “common resident in all parts, on 
prairie and in Ozark clearings.” 


Kentucky. The Prairie Horned Lark may have reached this 
state from Missouri, Illinois or Indiana, regions where it has 
for long existed as a breeding form. However, the first ap- 
parent breeding records for Kentucky are very recent. Howell 
(1910), saw a pair in Midway, July 9, 1909, that were prob- 
ably breeding forms and Blineoe (1925, p. 411), in his ‘‘Birds 
of Bardstown, Nelson County, Kentucky,’’ describes it as a com- 
mon winter bird and believes ‘‘it will be found breeding 
eventually.” 


History 21 


Primitive Range—In this extended account those regions 
into which the Prairie Horned Lark has penetrated, apparently 
within recent times, have been most carefully surveyed. The 
earlier home of this form and the base region from which all 
this recent movement extended will be more briefly noted. 

Coues (1874) gave Iowa and Minnesota westward as the 
range of the then subspecies leucolaema from which praticola 
was later split off. Henshaw (1884) had specimens in breeding 
plumage from Minnesota and eastern Kansas (in addition to 
Missouri, Wisconsin, Michigan, New York and [Illinois—see 
above). Dwight (1890) included eastern Kansas, eastern 
Nebraska, eastern Dakota and Manitoba with the western limit 
at the line when prairies cease and plains begin which ‘‘is also 
nearly coincident with the north and south line of twenty inches 
annual rain-fall.’’ Oberholser (1902) did not include more 
territory on the west than did Dwight. 

It is probable then that the home of the Prairie Horned Lark, 
prior to 1870, was restricted to that great prairie region that 
began with eastern Illinois, extended through Iowa, Minnesota, 
northern Missouri and the eastern ends of Kansas, Nebraska, 
South and North Dakota together with all the south half of 
Manitoba. Here it probably flourished in large numbers ready, 
as soon as the hand of man provided the proper conditions, to 
move out into all territory that the axe and the plow so un- 
wittingly made suitable. 

Henshaw (1884) gave as the distribution of this Lark, as 
already noted, the ‘‘upper. Mississippi Valley and region of the 
Great Lakes’’ with specimens in breeding plumage from Min- 
nesota, Wisconsin, Michigan, New York, Illinois, Missouri and 
eastern Kansas. Dwight (1890) extended this range to include 
Manitoba, Dakota and Nebraska, Vermont and Long Island. 
Oberholser (1902) further extended it to the north shore of 
the gulf of the Saint Lawrence (in 1918, however, he excluded 
this region), into the New England States through Maine and 
south into Pennsylvania, and at the present time there is evi- 
dence to show that Otocoris alpestris praticola now breeds in 
all the territory from the Maritime Provinces south to Maryland 
(excluding New Jersey and Delaware) west through West Vir- 
ginia, probably through northern Kentucky, all of Missouri, 
eastern Kansas, north through eastern Nebraska, eastern South 


22 Trans. Acad. Sci. of St. Louis 


Dakota, eastern North Dakota well into Manitoba; east again 
through Ontario to the west end of the Gulf of the St. 
Lawrence. 

Of the origin of Otocoris alpestris praticola prior to its oe- 
cupancy of the prairie region of central United States but little 
ean be given at this time. The opinion of the writer is that 
the origin of this form must have come from a more southern 
Horned Lark than alpestris, enthymia or hoyti. This conclusion 
is based upon the remarkable physiological cycle of praticola 
that prompts breeding activities in March, long before condi- 
tions in much of its present range make such activities reason- 
ably successful. Such activities are logically explained only 
on the hypothesis that praticola has carried north with it, too 
recently for natural selection to have eliminated, a breeding 
season suited best to more southern, less rigorous conditions. 
Perhaps in eastern Kansas, Missouri and Iowa a March nest is 
profitable and perhaps praticola has been there for a very long 
time. 

This extensive account of the distribution and extension of 
breeding territory of praticola cannot be closed without re- 
ferring to a condition that seems to prevail in Europe with 
respect to Otocoris alpestris flava. Gatke (1895) gives the 
most extensive evidence of this, based upon his lengthy observa- 
tions in Heligoland. It will be necessary to quote him at some 
length: ‘‘There is probably no species which has so rapidly 
and in such numbers advanced the limits of its distribution 
as this Lark has done in the course of the last fifty years, and 
nowhere are its annually increasing migratory flocks displayed 
so abundantly, as at present is regularly the case in Heligoland 

uring the autumn and spring migrations. 

“Until the autumn of 1847 the Shore Lark was known here 
only from the examples shot by the brothers Aeuckens some 
ten years before that date; during the October and November 
of the latter year, however, the birds all of a sudden appeared 
im such large numbers that another gunner of the name of 
Aeuckens was able to shoot twenty of them in one day . 

The numbers increased steadily every year from that time.”” ’ His 
— further give a range of from ‘‘several daily’’, 1850, to 

thousands’’ in 1884. Gatke goes on to say: ‘‘the original 
home of the Shore Lark is North America . . . . By degrees 


History 23 


this species has advanced its nesting stations throughout the 
whole of northern Asia and Europe as far as Scandinavia, and 
there is no doubt that it will next establish itself in the north 
of Scotland; there might then result the most interesting fact 
of some of these birds flying across the Atlantic back to their 
original home as exceptional visitors . . . . This species must 
have displayed, even from its origin, a strong inclination for 
a westerly autumn migration, for otherwise it could never have 
got across into Asia and finally to Lapland and Finmark.’’ 
The above assumed extension of range is argued against at 
length by Naumann who twits Gatke for his notions as follows: 
‘‘Anzunehmen, das die Art vor ihrer Entdeckung als Brutvogel 
in Lapland nicht dort genistet hatte, ist dusserst gewagt.’’ 
I ean find no evidence that Gatke implies that the bird did not 
nest in Lapland prior to its discovery there. But Naumann 
goes on: ‘‘wenn man den Fall vorurteilsfrei [italics mine] 
betrachtet, so verhalt es sich mit den Beweisen fiir Gatkes An- 
nahme gerade wie mit denen fiir die fabelhafte Wanderung des 
Blaukehlechens und der ‘Umfarbung’ gewisser Vogel ohne 
Mauser.’’ And then he gives Barrow’s argument (see above) 
to disprove the extension: ‘‘Es mag ja immerhin sein, dass die 
Art durch ihren Bruten giinstige Jahre in neuerer Zeit haufiger 
geworden ist aber in iibrigen geniigt zur Erklarung ihres ver- 
meintlichen haufigeren Auftretens der Umstand das eben heute 
mehr beobachtet wird.’’ 
However that may be there are others of Gatke’s mind. 
Saunders (1899), for instance, says that it ‘‘has undoubtedly 
spread westward from America in recent times and is still ex- 
tending its range in that direction.’’ With this very probable 
extension of range of a closely related form in Europe in a 
country long stabilized as to forests and cultivation, the record 
of praticola in this country becomes the easier to understand. 


MIGRATION 


south, but is, on the whole, very poorly | 
result of the rather desultory, more or less random movement 


24 Trans. Acad. Sci. of St. Louis 


of a bird that is not migratory in the full sense of the word. 
Unlike Otocoris alpestris alpestris which moves entirely from 
its summer range in winter, O. a. praticola may be found 
throughout the year in the southern limits of its breeding range. 
Whether all individuals of this subspecies move south in winter, 
northern forms replacing southern in southern Illinois, Missouri 
and Kansas and the breeding forms of these regions moving 
further south, or whether the birds here are permanent resi- 
dents, that is sedentary, and the northern forms pass over their 
heads to regions further south cannot be said. Such questions 
can be answered only by marking or banding individuals. What- 
ever the case may be, individuals are never lacking, at any time 
of the year, throughout the southern half of the breeding area 
and even on the northern border representatives are rarely want- 
ing for more than six weeks or the two months of December 
and January. 

Henshaw (1884) notes that it occurs in Texas in winter; 
Dwight (1890) records it from South Carolina and central 
Texas; Oberholser (1902) gives the Carolinas, Kentucky, Texas 
and easually west to Colorado and Arizona. Smith (1912) 
writes that it arrives November 9 and leaves March 20 in Mont- 
gomery County, Virginia; Brumley (1893) says it was com- 
mon at Raleigh, North Carolina, in December, 1885, again with 
O. a. alpestris in January, 1887, and in small numbers January, 
1893. Loomis (1887) took O. a. praticola in Chester County, 
South Carolina, early December, 1886. He records (1888) great 
numbers in December and January; of these he collected, in 
December, 119 of which 103 were females and only sixteen 
males. In January he collected thirty females and only ten 
males. This amazing discrepancy in sex is a phenomenon of 
migration the explanation for which is not clear unless it be 
that the males, more attached to their breeding territories, 
remain nearer to them, or begin their return to them much 
earlier than the females. Loomis (1891) continued these obser- 
vations with similar results. He notes, in addition to the dis- 
erepancy of sex (42 males, 225 females in birds shot in 1887, 
1888 and 1890), that the first arrivals appear the last week in 
November. 

Wilson (1922) calls the Prairie Horned Lark a common win- 
ter resident at Bowling Green, Kentucky, noted from July 28 


Migration 25 


to May 11. Cooke (1908) took praticola in Georgia (Clayton 
County, November 30, 1907). Isley (1912) tells of this sub- 
species in Sedgwick County, Kansas (middle south region). 
Cooke (1914) in recounting the winter birds of 1883-4 at Caddo, 
Oklahoma, remarks, concerning the Prairie Horned Lark, that 
it appeared in large flocks October 26, remained constantly and 
in numbers to January, decreased from then to February 18; 
none on February 20; a few in pairs March 8. Lastly, among 
those records of birds wintering south of their breeding range, 
is that of Attwater (1892) who ealls O. a. praticola a common 
winter resident of San Antonio, Texas. 

As previously noted, the Prairie Horned Lark is absent as 
a species for a period of about six weeks to two months in the 
winter toward the northern limits of its breeding range. The 
last noted in 1925 at Evanston, IIl., was a single individual on 
November 27, the first returned January 10, 1926. The migra- 
tion dates for Ithaca, N. Y., from 1908 to 1921, are as follows: 


Year First Seen Became Common Last Seen 
1907 Feb. 17 Feb. 24 Nov. 19 
1908 Jan. 22 Feb. 23 Nov. 3 
1909 Jan. 9 Feb. 12 Nov. 7 
1911 Feb. 9 Feb. 9 

1912 Jan. 28 Mar. 7 Oct. 18 
1913 Jan. 26 Feb. 19 Oct. 26 
1914 Jan. 6 Feb. 14 Dec. 8 
1915 Jan. 26 Feb. 18 

1916 Jan. 16 Feb. 20 

1917 Jan. 8 Nov. 28 
1919 Jan. 18 Nov. 15 
1920 Jan. 8 Feb. 29 Nov. 6 
1921 Feb. 8 Feb. 21 Oct. 30 
Average Jan. 23 Feb. 21 Nov. 9 


Mouseley (1916) gives March 15 as the average date of arrival 
(for four years) at Hatley, Stanstead County, Quebee. He 
mentions (1924) a ‘‘last’’ record on November 26 ‘‘three weeks 
later than any previous date.’’ Scott (1884) mentions the 15th 
or 20th of February for Ottawa, at Belleville, February 9 or 10, 
for ‘‘Eremophila alpestris”. ifrig (1911) gives as early as 
February 10 for Ottawa, latest November 22, 1908. Soper 


26 Trans. Acad. Sci. of St. Louis 


(1923) says that it ‘‘reaches us in late February or early 

arch . . . . leaves about November 10,’ in Wellington and 
Waterloo Counties, Ontario. Barrows (1912) writes that it is 
ordinarily entirely absent from the state (Michigan) during 
December and January. Finally Criddle (1922) gives the fol- 
lowing dates for Aweme, Manitoba, the most extensive observa- 
tions, apparently, ever made of the migration of this subspecies: 


Spring migration (Aweme, Manitoba) 


Number of years Average first date Earliest 
25 Feb. 21 Feb. 9, 1918 
Fall migration (Aweme, Manitoba) 
Number of years Average date last observed Latest 
24 1 Nov. 23, 1917 


Summary of general migration—The Prairie Horned Lark 
is not extensively migratory, belonging, in the categories of 
migration, between a form such as O. a. alpestris which moves 
entirely from its summer home for a long period and the almost 
sedentary species such as O. a. giraudi which is said to be found 
throughout its breeding range during the entire year. The 
southern limit of the winter range of praticola is South Carolina 
(occasional in Georgia), and Texas, and at this limit the bird 
oceurs in December and January. Many spend these two months 
also in Kansas, Oklahoma, very probably in Missouri and in 
Kentucky. From middle to late November into late January 
or early February Otocoris alpestris praticola is absent from 
New England (Vermont, Parkhill, 1889), New York, Quebec, 
Ontario, Michigan, Indiana (Butler, 1897, who says December 
first to January twenty-fifth usually) and Manitoba. The situa- 
tion is, undoubtedly, the same for all other territories, of similar 
latitude, where the Prairie Horned Lark breeds. 

tion of sexes and individuals—But little can be said 
at this time, as to the arrival of sexes, of mature and immature 
birds and of resident and non-resident individuals in any given 
locality. If all these forms were characterized by diverse plum- 
age as the Red-winged Blackbird (see Allen’s, 1911-13, most 
excellent account of the migration of this form), the problem 
would have greater possibilities of solution. But since mature 
and immature birds in spring have no distinguishing charac- 
teristics in the field, and since sexes can be distinguished only 


Migration 27 


when closely approached, the only method whereby an adequate 
knowledge of the details of migration could be obtained would 
be that of extensive collecting and sexing of many birds through 
Several spring and fall seasons. No attempt has been made, as 
yet, in that direction. 

However, some general observations have been made in this 
regard. First of all it seemed evident that the first birds that 
arrived, both at Evanston, Ill., and at Ithaca, New York, were 
resident males. Though this is not in accord with Allen’s (1911- 
13, p. 77) observation of the Red-winged Blackbird, still it 
seems strongly conclusive in the case of the Prairie Horned Lark 
because of the following facts: (1) the first Larks to arrive at 
Evanston (January 10), were not in flocks but distributed them- 
selves singly (one pair was noted) over the breeding area; (2) 
full ground songs and one typical flight song were noted January 
12 and much fighting was in progress between males. The same 
observations were essentially true at Ithaca, New York, the 
spring of 1927. The first Lark noted at this place was a single 
individual observed by Dr. A. A. Allen, February 3. The first 
Larks appeared on the breeding grounds February 9 and, when 
first observed, were scattered over it singly, singing or indulging 
in aerial combats. 

Resident females are, it appears, the next to arrive. Some of 
them come very shortly after the males. Though Criddle (1917) 
writes that the males precede the females by two weeks at 
Aweme, Manitoba, I believe some females come with the first 
males or very shortly thereafter. What seemed to be a mated 
pair was noted with the first Larks, January 10, 1926, at Evans- 
ton, and several pairs were noted January 16, though unmated 
males seemed to be as numerous as mated on January 23. How- 
ever there were males only on the territory February 5, but two 
days later paired Larks were numerous and mating activities in 
full swing. At Ithaca, New York, 1927, the first birds to appear 
on the breeding grounds (February 9), seemed to be males only 
but a mated pair was noted February 19, as well as one unmated 
Male. : 

Transients or migrants, i. e. birds still in flocks and flying 
over, perhaps to more northerly breeding grounds, are frequently 
noted in late February and in March at Ithaca, New York. Thus 
on March 12, 1916, a flock of one-hundred was noted; similarly, 


28 Trans. Acad. Sci. of St. Louis 


on February 21, 1927, a flock of about the same number was seen 
by Dr. . Allen. It is quite possible that these flocks may 
represent penident birds, however, for on February 21, 1927, 
nearly a foot of soft snow was on the ground and this flocking 
may have been a secondary reuniting of resident birds forced, 
temporarily, from their territories. Jones (1910), has noted 
that the Prairie Horned Lark refiocks after mating in the spring 
if severe weather modifies its breeding areas. The present writer 
noted that prolonged and deep snow at the end of March, even 
after nests had been started, caused the birds to desert their 
territories and to collect in groups along the roadsides at Evans- 
ton, Illinois. Even though this may account for some flocks in 
February and March it remains true also that Larks must pass 
over to reach breeding areas to the north and these very prob- 
ably do so in February and March after residents are established. 
Small flocks were noted at Evanston February 28, 1926, long 
after residents had come onto their breeding grounds, similarly 
a small flock of ten to twelve birds was flushed from a patch of 
Setaria at Ithaca, March 1. Again small flocks were noted once 
or twice in April at Evanston but these proved to be O. a. alpes- 
tris and not praticola (for which see under account of birds that 
fed over or on the subdivisions at Evanston, Illinois). 

Vagrants, immature or unmated birds appeared occasionally at 
Ithaca, New York in April, but since the mated males drove 
them out of the vicinity whenever they attempted to alight, it 
was impossible to ascertain their sex. It is possible, though 
improbable, that they represented young of successful March 
nestings. 

of migration of sexes and individuals—The fol- 

lowing very tentative categories of spring arrivals may be listed 
in summary in the order of their arrival: 
Resident adult males 
Resident adult females 
Transient males and females 
Vagrant, immature, etc. 


i oF: oe et 


THE LARK IN AUTUMN AND IN WINTER 


Under migration something has been said of the movements 
of the Prairie Horned Lark in late fall, in winter and early 
Spring, in various portions of its range. There remains yet a 
short discussion of what may be known of its other activities at 
this season: its flocking, its food, its associates, and, especially, 
its habitats. 

Flocking.— Young of early broods begin to gather in small 
groups in late spring and early summer long before the adults 
have ceased breeding activities. Thus small bands of juveniles 
were seen at Evanston, June 19, 1925. In 1926 at Evanston 
the first flocking of adults was noted on July 31. At Murdock, 
Nebraska, August 24, 1926, a large flock was discovered scattered 
out over a large tract of recently plowed ground. In September, 
at Murdock, Larks were frequently heard in the air and one 
essayed a flight song September 6. In October and November, 
1925, at Evanston the only Larks seen were casual groups of 
twos and threes on or above the breeding grounds west of the 
city. They were noted thus October 25, 31, November 8, 21 and 
27. At Ithaca, New York, during the fall of 1926, Larks were 
heard frequently flying over the Campus of Cornell University 
and Dr. A. A. Allen and Mr. M. D. Pirnie reported a typical 
flight song on November 6. The appearance of this bird in the 
Carolinas, Kentucky, Oklahoma and Texas during December 
and January has been discussed under migration and its reap- 
pearance in the latitude of northern Illinois (Evanston) and 
south central New York (Ithaca) has also been considered. 


Habitats——The conditions preferred by young or by adults 
in fall or winter do not differ materially from those in which 
the species breeds. These conditions are those of the open field 
and areas in which a minimum of vegetation prevails. The 
close-cropped pastures, the great fields of fall plowing in the 
Missouri Valley, closely mowed cemeteries (Evanston, July 31, 
1926) are examples of conditions in which Prairie Horned Larks 
have been found at these seasons. Though the surveys of Forbes 
and Gross (1922) were made in early and late summer they do 
not differentiate between breeding and non-breeding birds so 
these records will be considered here. They show the Prairie 

29 


30 Trans. Acad. Sci. of St. Louts 


Horned Lark as the dominant form of plowed ground bird and 
show, as well, that more were found in such conditions (162 in- 
dividuals of a total of 710) thanin any other. The next most fa- 
vored habitats they list are pastures, then wheat, rye and barley 
fields, then meadows, then corn (of early summer undoubtedly 
with much bare ground between rows), then stubble, then oats, 
with but a single record from waste and fallow ground (very 
probably because it is weed grown at this season). As might be 
expected not a Lark was recorded from woods, orchards, shrub- 
bery or swamps. The young Larks especially show their inher- 
ited taste for the bare, verdure-wanting localities and in these 
they will be found in June and July while their parents, forced 
by the exigencies of second and third broods and the inability to 
move nests from the flora that grows rapidly about them, are 
forced to spend much time in conditions they would not naturally 
favor. The young at that time are a more proper index of the 
optimum habitat of the Prairie Horned Lark. Loomis (1891) is 
one of the few who describes the conditions in which wintering 
flocks are found in the south. These, in South Carolina, are barren 
upland pastures where grass has been cropped to the roots, 
wind-swept grain fields, cotton fields where stalks are small and 
the ground free from grass. As birds of the barrens one would 
not expect Larks to alight in trees freely, nor on wires. Indeed 
Sutton (1927) says ‘‘I have never seen one alight on any leafy 
bough, bush or wire’’. Such is generally true, but Mouseley 
(1916) remarks the Larks of a breeding pair alighting in a tree 
before approaching the nest, and the writer has seen the singing 
males at both Evanston and Ithaca frequently on posts, stakes 
and building tops and the ‘‘B’’ male now and then alighted, 
insecurely, on a smooth wire stretched above the garden at 
Ithaca. Eifrig (1902) reports Prairie Horned Larks coming 
into the city streets in Maryland and there eating with the House 
Sparrows when snow covered their normal food supply. Those 
incongruous homes, the icy, boreal-blasted fields to which the 
Prairie Horned Lark returns in January and on which he begins 
his songs, though the temperature may be zero, are a part of the 
breeding season and under that they will be considered. 
_ Associates in fall and winter—The Prairie Horned Lark is 
essentially alone in his choice of habitats in the breeding season, 
none other approaches the desolate ecological niche in which he 


The Lark in Autumn and in Winter 31 


is content ; but in winter birds from farther north, from Aretic 
tundras and barrens, share with him his favorite flocking 
grounds. Thus Brimley (1893) reports Prairie Horned Larks 
associating with Horned Larks at Raleigh, North Carolina. At 
Evanston also the Horned Lark found the home of praticola 
suitable for a temporary abode and great flocks of Lapland 
Longspurs ran about on the barren flats apparently as much a 
part of that environment as the Larks themselves. 

Nightly quarters—Apparently the Larks remain where 
night finds them on the open areas. No endeavor is exercised 
to locate any shelter other than that of sparse grass clump or 
available clod. Nor do they cluster tightly but pass the night 
in the same scattered groupings that they maintain while feed- 
ing. Sutton (1927, p. 132) describes the awakening of a flock 
wherein the ‘‘creatures left their roosts beside or beneath little 
clumps of grass’’. After a heavy snow at Evanston, Illinois, I 
have noted virgin morning tracks of Larks emerging from the 
shelter of scant grass clumps where the snow had made roofed 
shelters for them. 

Food in fall, winter, and early spring—McAtee (1905), in 
his extensive account of the food of the Horned Larks, writes 
that in August and September many grasshoppers are taken 
(7.1 and 8.9 per cent of the total food respectively), and that 
weevils constitute 18 per cent of the food in August. He says 
further that spiders are taken in every month. The conspicuous 
weed seeds which he lists (foxtail grasses, smart weeds, bind 
weeds, amaranth, pigweeds, purslane, ragweed, crab and barn 
grasses), are probably largely consumed in fall, winter and 
early spring. The total of 79.4 per cent of vegetable matter 
taken in the year, as given by McAtee, is made up largely of 
these weed seeds. McAtee found about 40 per cent of food taken 
in August to be animal matter, 20 per cent animal matter in 
September, between 10 and 20 per cent in October, 5 per cent or 
less in November, about 2 per cent in December, 1.73 per cent 
in January and 3.11 per cent in February. The animal matter 
of January and February consisted principally of weevils and 
cocoons of Tineid Moths. Grain (chiefly waste oats, corn and 
wheat) formed 12.2 per cent of the food of Larks (exclusive of 
California forms) and much of this would have been taken in 
the period under consideration. 


32 Trans. Acad. Sci. of St. Louis 


The Main Subdivision at Evanston, where the most extensive 
observations were made by the present writer, had, in the winter 
of 1925-26, great quantities of Agropyron repens (quack grass), 
Setaria (foxtail) and Amaranthus (pigweed) all of which had 
been allowed to mature seeds. Of this the seeds of the quack 
grass were eaten first and wherever their long stems had fallen 
over the sidewalks the Larks would invariably be found in 
January and February. When quack grass failed, foxtail was 
eaten, and lastly Amaranthus substituted when no other seeds 
were available. Plate IV, Fig. 1, is a photograph showing results 
of Lark activities about a clump of Amaranthus after a March 
snowstorm. Once or twice Larks were noted along the roads 
feeding on the oats of horse droppings, when snow covered up 
all the weed seed of the subdivision. And again at Ithaca the 
compost heaps, put out for fertilizer along the garden margins, 
supplied some food when snow lay deeply over the ground. 


At Ithaca, during the spring of 1927, Prairie Horned Larks 
were observed feeding on Setaria (March 1), on Ambrosia 
artemisiaefolia April 1; a pair of Larks were frightened away 
from an Arctiid moth larva (Apantisis arge) which I observed 
the female dig up, March 3. Finally a few adults were collected 
in March at Ithaca (Connecticut Hill) and examination of 
stomach contents gave the following results: 


1. Female, March 6, collected about 6:00 P. M. 


Vege Ne 8 es ss ee eee 98% 
PAN) oss es ee 10% 
capped Sigs = SO0GS) os oe es 88% 
MIA) Wentiee: SS ee ies aes % 
bits 4 t iT as a 1% 
SROGt Hectie (ol). 495534 oe 1% 
2. Female, March 11, collected about noon. 
Boge UREEOP Soi oy oes epee 95% 
kewheat (one whole grain and many 
PR ae aes ra are ee 90% 
Polygon aa persicaria (four seeds)...... 5% 
Be 8 ee ee ee ee 5% 
3. Male, March 11, collected about noon, 
wetocenie MOnitG? |. Ss se ns es 100% 
ie (One erat) 2 se es 5% 
Setaria, two species (46 seeds)......... 95% 
4. Male, March 11, collected about noon, 
eines Na i eins 100% 
Daskivhoat _esemante of grains)... .<. 10% 
erares (00 gies)... 6s 90% 


The Lark in Autumn and in Winter 33 


5. Male, March 11, 


Vegetable matter ......62335152 ee ee 100% 
Ambrosia pobtiiae ote (three seeds). pod 
Setaria (eight seeds)...............000% 10% 
6. Male, March 11. 
Vegetable Inattet <hr a 100% 


rosia artemisiaefolia (six seeds)...50% 
Setaria, two species (seven seeds)....... 50% 

In summary of the feeding habits of the Prairie Horned Lark 
in autumn, winter and early spring, all that need be said is that 
the bulk of food taken is that of seeds of weeds, and the animal 
food, a much smaller per cent, is almost entirely of those forms 
which are harmful to the agriculturist. The Lark, in feeding 
habits, finds for his food those things that appertain to the waste 
lands that he inhabits. 

Call notes.—The Horned Lark, like the Goldfinch, usually 
advertises himself in flight by a definite, unmistakable note. 
Excepting an occasional song, this is about the only sound from 
the birds in fall and winter. Reed (1923) describes this flight 
note as “‘tseet’’ and Knight (1908, p. 325) puts it into such 
words as ‘‘we-tseet’’ or ‘‘weechy-weer’’. 

The flight and eall notes are several in number however, some 
of them appertaining more especially to the breeding season than 
to wintering birds and in that connection they will be considered 
again. The chief stock in trade of the Lark and the one most 
commonly heard is ‘‘p-seet’’ or merely ‘‘zeet’’. It is uttered 
casually on the climb of the ordinary undulating flight, espec- 
ially on long journeys and in flights of young birds. Adults 
frequently make low flights over the ground without uttering a 
note. This ‘‘p-seet’’ is occasionally, sometimes frequently, 
lengthened to ‘‘p-seet-it’’ during the flight. When flushed the 
note is ‘‘zu-weet’’ or ‘‘zur-reet’’ (long drawn), ‘‘zeet-eet-it”’, 
or ‘‘zeet-it-a-weet’’, which is so high-pitched and mournful in 
character that it makes the birds indeed a part of the winter’s 
gale that whips them away. 

Flights—Breeding birds, such as females in abandonment 
concealment of the nest, or males in flight song, exhibit several 
distinct flights, but at other seasons the flight is of but one defin- 
ite character. This is a choppy undulation brought about by 
three or four rapid, even strokes of the wings interrupted by 
the space of about two beats during which the wings are closed. 


34 Trans. Acad. Sci. of St. Louis 


The note is uttered on the climb of each undulation. Or again 
on prolonged flights the character of the wing beats is as fol- 
lows: Long strokes are made, one, two, three (or one, or one, 
two), with a pause of about one wing beat between each stroke 
wherein the wings are folded. Then come four to six rapid and 
successive strokes which cause a climb. At this time the note, 
‘‘zeet-it’’ is uttered. Then comes a pause of the length of one 
or two beats, with wings folded, causing a drop in elevation. 
These repeat. The bird goes thus: jump, jump, jump, climb 
(call also), drop, jump, jump, jump. 


REPRODUCTION 
Breeding Habitats 

General—Other writers give the following habitats for 
the nestings of the Prairie Horned Lark: On ridges of 
corn (Isley, 1912, Kansas) ; beside hills of corn (Crone, 1889, 
Iowa); meadow-highland and cornfields (Jones in Davie’s 
‘“‘Nest and Eggs of N. A. Birds’’, 1889, Iowa) ; first nest in 
closely cropped pastures, June nests at the hills of corn (Hess, 
1910, Illinois) ; grass-sparse uplands, not prairie (Criddle, 1917, 
Manitoba) ; between the end of ties of the Canadian Pacific 
Railroad (J. F., 1900, Ontario) ; in old meadows (Eifrig, 1911, 
Ottawa) ; on ploughed fields (Soper, 1923, Ontario) ; inside of 
manure heap in a field (Davison, 1885, New York) ; fallow fields, 
prairie tracts, pastures, country roads (Bendire, 1895, general) ; 
early nests in meadows and pastures, later in potato and cab- 
bage fields (G. E. Harris account in Bendire, 1895, New York) ; 
in the oval of a race track in Schenley Park (Brooks, 1908, Pitts- 
burgh, Pennsylvania) ; in the middle of a golf course (Burleigh, 
1923, Pennsylvania) ; dry undulating field, ground more or less 
covered with snow, in bed of hair-cap moss, another in a damp 
meadow (Mouseley, 1916, Stanstead County, Quebec) ; in a sheep 
pasture on top of mountain, very unprotected (Brewster, 1894, 
Massachusetts) ; in an old plowed field too wet to sow (Swain, 
1900, Maine) ; in fields and pastures, sandy barrens (Tufts, letter 
of June 21, 1927, Nova Scotia), in a field of young oats drilled 
into a former corn field (Forbes and Gross, 1922, Illinois). 

That the other subspecies of Otocoris alpestris select the ver- 
dure-denuded opens can also be shown by a few references: dry 
and bare ridges in a wet meadow (Merrill, 1888, 0. a. strigata 


Reproduction 35 


in Oregon) ; bleak and barren . . . plains (Batchelder, 1885, 
O. a. chrysolaema in New Mexico) ; in park-like openings in the 
mountain forests up to an altitude of 10,000 feet (Mearns, 1890, 
O. a. adusta in Arizona) ; on bleakest and most exposed hillsides 
(Bigelow, 1902, O. a. alpestris in Labrador); on prairies, in 
denser vegetation than O. a. praticola (Criddle, 1917, O. a 
enthymia in Manitoba). 

In summary of these accounts three or four things are to be 
pointed out: (1) the Prairie Horned Lark selects the bleakest 
barrens available in every locality in which to nest. These may 
become weed grown during the nesting but the optimum condi- 
tion, the criterion of the Lark’s choice, is the condition of these 
localities when the site is selected and the nest built; (2) the 
“‘barren’’ condition is, apparently, that which possesses little 
or no verdure. Moisture, elevations, nature of soil, are all sub- 
servient to that one requirement—bare ground; (3) from the 
close-cropped pasture (an ideal ‘‘barren’’ in March), the Larks 
are driven by press of verdure in May; then they select the last 
bare ground available—the gardens, the cultivated fields; (4) all 
other subspecies of the Horned Lark seem to resemble the Prairie 
Horned Lark in their selection of nesting sites though 0. a. 
praticola, exceedingly versatile, has invaded those ‘‘barrens 
that civilized man so artificially creates. 

The breeding territory at Evanston—About one and one- 
half miles from the west limits of the city of Evanston, Illinois, 
and about two and one-half miles north of the north bounds of 
Chicago, lies the bit of territory which was worked most thor- 
oughly in this study. This, like many hundreds of acres on all 
sides of it, was, until a few years ago, an extensive marsh. At 
that time it was, manifestly, unsuited as breeding grounds for 
the Prairie Horned Lark. 

Portions of this marshy area were, with difficulty, put under 
cultivation after a drainage canal had partially removed the 
water, but much remained unutilized and weed-grown. That 
area, which later became what is called the ‘‘Main Subdivision”’ 
in this paper, was one of these weed-grown regions and a smaller 
area just west, here called the ‘‘ West Subdivision’, was put into 
gardens. Here it is well to call attention to the fact that, though 
the Larks might have nested in the gardens of the West Sub- 
division, they could not have nested in the Main Subdivision 


36 Trans. Acad. Sci. of St. Louis 


until the time of the changes about to be related. That they 
came onto this area in great numbers within two years after its 
conversion is but another evidence of the striking versatility of 
the Prairie Horned Lark in acquiring new breeding territory. 

The weed-grown condition of the one area remained unmodi- 
fied until 1923 or 1924, at which time the entire surface, very 
flat previously, was altered to form a golf course. Drainage was 
completed, artificial hazards created, bunkers, greens established, 
mounds were thrown up here and there. Though the area was 
not under close observation at that time it is quite possible that 
a few Larks may have nested on the margins of the sand hazards 
as they do on many golf courses in their range. 

The golf course was short-lived. In the fall of 1924 a branch 
of the Chicago Elevated Railroad penetrated to the vicinity. 
Promptly the erstwhile golf course was subdivided; sidewalks 
stretched themselves out over night, whirling lot-sale signs clat- 
tered everywhere and those indefatigable, hopeful pillars of 
progress, the street sign posts, soon stood like solitary glistening 
martinets on the otherwise uninterrupted landscape. 

But this, the Main Subdivision, became a paradise to the 
Prairie Horned Lark. In the spring of 1925 the grass of the 
former course was burned off and the whole subdivision pre- 
sented a blank, black, almost smoothly denuded face. Here the 
Lark was at home. Even in June, in areas in which vegetation 
came on slowly because of scraping or sanding for former 
hazards, nesting was still in progress. During the summer of 
1925 sewers were laid in the street-ways, north and south, and 
this activity threw up a mound of dirt thirty to forty feet wide 
in the center of the street, a strip that grew no verdure until 
late summer, 1926. And so, at its edge, in the thin grass strip 
between it and the sidewalk there were provided sites for fifteen 
located nests of the Prairie Horned Lark (see Fig. 9; Plate III, 
Fig. 1; Plate XII, Fig. 1; Plate XIII, Figs. 1 and 2), during 
1926. 

In 1926 the Main Subdivision began the nesting season with 
closely clipped, dread grass of Agrostis palustris (red-top), and 
Poa pratensis (blue grass), with here and there, in old hazar 
coarse stems of dead thistle (Cirsium arvense), primrose (Oend- 
thera biennis), ragweed (Ambrosia artemisiaefolia), white, sweet 
clover (Melilotus alba). Much of the ground though, was bare ~ 


Reproduction 37 


and black where the grass had been burned off. Throughout 
April the only verdure was the green tips of new grass but in 
May the dandelion (Taraxacum officinale) made all the area a 
great field of yellow; dandelion gave way to blue grass in June; 
blue grass to red-top; and by July the whole surface, even most 
of the streetways, were grown up in heavy verdure. As the plant 
life grew the Larks were forced first from their nest sites within 
the blocks, secondarily from their narrow strip near the street 
mounds and lastly, in late June, even from the hazards whose 
depressions, stripped and sanded, nevertheless, under the 
influence of the summer sun, produced too much vegetation for 
the Larks. But what was inhospitable to the Prairie Horned 
Lark proved the most acceptable home to many another bird. 

The West Subdivision (bordering the Main Subdivision on 
the west), as previously stated, had been a garden plot for some 
time but it, too, suffered subdivision, though not until the spring 
of 1926. Having had no grass, and having been cultivated the 
year before, the weeds grew slowly in 1926 and here, among the 
scattered clumps of wild mustard, bindweed, lamb’s quarter, 
cocklebur, wild lettuce and thistles, on the last bare ground the 
vicinity offered, the July nests of the Lark were found. 

The breeding territory at Ithaca.—One nest was located on 
the overturned sod of a former meadow (see Plate X, Figs. 1 
and 2). This nest was destroyed by cultivation and the first 
attempt at renesting was destroyed by oat-sowing, but it is prob- 
able that one nesting may have been successful during the weeks 
the oats were getting under way. 

The most extensive study was made of a series of nestings, 
just east of Ithaca, on an uneven tract that was in part devoted 
to gardening and in part to fall wheat and fall rye. The fall 
wheat area remained suitable for nesting from March, through 
April and well into May, though by the middle of May the wheat 
and rye had attained such a height that only the urge of nest- 
lings would have kept the Larks in it. By June one pair of 
Larks had gone from the wheat area entirely and the other two 
pairs no longer occupied the portions of their territories that 
formerly had extended onto it, but restricted themselves to the 
bare areas of the garden (see Figures 2, 3 and 4). 


38 Trans. Acad. Sci. of St. Louis 


Song 

Season of song.—The extent of the season of song is a sub- 
ject upon which there is little or nothing in the literature. I 
have before me only the following records that give dates of the 
beginning of song: Isley (1912), Sedgwick County, Kansas, 
writes that they begin to sing about the middle of January; 
Langille (1912) gives ‘‘as early as the last days of February’’ 
Knight (1908, Maine) writes that the ‘‘male bird begins to sing 
in late March or early April’’; Chapman (1923, quoting Seton) 
gives ‘‘springtime while the snow is yet upon the ground’’. 
Criddle (1920) reports ‘‘males singing everywhere’’, July 14, 
Manitoba. The following ‘‘late’’ record is by Seton (1908) for 
the subspecies O. a. hoyti, which was in full song on the Barrens 
in the Great Slave Lake region, August 29, 1907. 

As previously noted, the first Larks returned to the breeding 
grounds at Evanston, January 10, 1926; the first song (from 
the ground) was heard January 12 while a stiff gale blew out 
of the northwest and the mercury was near zero; the first flight 
song was noted January 16 and extensive song activity was in 
progress from that day on, except in the most severe weather 
conditions. The last song in 1925 was on July 4 (both ground 
and flight songs), the last flight song in 1926 was on July 3; on 
July 14, a short ground song concluded the season. It should 
be noted here that songs diminished gradually and ceased alto- 
gether fully two weeks before nesting duties had been brought 
to a conclusion. Flight songs were noted September 8 and 
November 6 but had no relation to the breeding season, naturally. 

At Ithaca the first songs (flight and ground) occurred on 
February 19, the last of the season on June 25, 1927. 

There is probably no other Passerine bird that can equal this 
record. What an urge it must be that starts these birds off on 
their snow-covered, wind-swept, zero-cold barrens in January, 
and keeps them at it through March squalls, April showers, May 
storms, June sun and on into July heat, day after day, hour 
after hour, from matins to vespers, from month to month! 

Monthly variations in song numbers.—It is possible only in 
Ter general way to state how the relative number of songs 
varied from month to month. In the case of ground songs sta- 
tistics are, quite obviously, impossible for an entire season for 


Reproduction 39 


there is no clear beginning nor ending to a song upon the ground 
unless one counts each rendering of the intermittent ditty, and 
all songs are not of this type. However a reasonably careful 
tabulation of all flight songs was made on every visit both at 
Evanston and at Ithaca. Now if we consider that the average 
length of a visit was the same in all months and if each month 
is properly weighted and averaged according to the number of 
visits, then at least relative figures may be obtained for the 
entire season. Thus of five January visits one flight song was 
observed, a percentage of .200 flight songs per visit. Similarly, 
in February, fourteen visits were made and six flight songs 
noted, a percentage of .428 flight songs per visit. Using this 
as a method of estimating amount of flight songs throughout the 
months of song we have the following tabulation: 


Average number of flight songs noted per visit from January 


to July 
January .200 per cent 
February 428 =“ 
March 160 
Apeik sso Soe ae ee Lon 
May 2.022 ‘° 
June igs. 2! 
July eee 


These figures are exceedingly conservative as far as total num- 
ber of songs may be concerned but they are pretty close to the 
truth as far as percentages are concerned. May is the optimum 
beyond question. May is probably the optimum in all respects 
as far as the entire breeding season is concerned (see below under 
enemies of young). June, as given here, may be a little too high 
for more time was spent per trip during this month than during 
other months. But even as given it shows the dropping off in 
flight song in this month, a dropping off which, in July, becomes 
very great indeed. Incidentally the total number of recorded 
flight songs was 287. 

There is, of course, a variation in songs dependent upon 
weather conditions. Fewer songs are sung when the weather is 
bitterly cold, especially if the day is also dark, though I have 
watched these birds, in February and March, climb into a stiff 
northwest gale, when the thermometer registered many degrees 


40 Trans. Acad. Sct. of St. Louis 


below freezing, and for several minutes fight Boreas above that 
they might release the terrific energy that impelled them to song. 
Violent winds, on the whole, whether cold or mild, checked aerial 
song though rarely inhibited it altogether. Quiet, clear days 
were made much of but flight songs were as frequent, perhaps 
more so, when light clouds overcast the sky. Observations were 
made and records obtained on all of these points but opportunity 
has not presented itself, as yet, to reduce them to definite tables. 

Variations in song through a nesting period—Here again 
no definite statistics can be produced to show the relative num- 
ber of songs of the male during the period when eggs were in 
the nest as contrasted to the period when young were in the 
nest. The chief difficulty lay in the fact that, in flight songs for 
instance, it was impossible to identify the individual. Also, 
both at Evanston and at Ithaca, there were nests with young, 
as well as nests with eggs, in the same region at almost all times 
during the breeding period, so that the total number of songs 
was not materially influenced by the condition at any one nest. 
Some general observations indicated that the period of most 
vigorous song was that of nest building, egg laying and ineuba- 
tion and, since the male assisted in feeding the young, the period 
of least singing was that when young were in the nest. For 
evidence of this compare the table of activities of the male when 
eggs were in the nest (Table 15) with the activities of the male 
when young were in the nest (Table 17). This latter male did 
no singing from the ground that was noted and indulged in but 
one or two flight songs as far as could be ascertained. 

Variations in song throughout a day.—By referring to Table 
15 it can be seen that ground songs are distributed with remark- 
able regularity throughout the entire day, but there is some eVi- 
dence in this table and from other observations that a majority 
of the flight songs came toward noon, and again near sundown, 
though they were delivered at other times as well. It is with 
regret that I acknowledge insufficient data also on this point. 
Part of the difficulty is that the majority of visits were made, 
of necessity, in late afternoon. 


The relation of the song of the Lark to that of other birds.— 
How the Lark compared with the morning chorus in time of 
— his song and with what company he closed his choral 
efforts is a matter of considerable interest. Observations made 


Reproduction 4] 


on two or three very early morning trips to the breeding areas 
showed that most of the other residents preceded the Lark in 
Song, apparently because the day must be started with a flight 
song and for this some light is necessary. Thus the Purple 
Martins on June 16, 1925, were chattering in the air by 3:20 
A. M., a full-throated Robin song at 3:30; a Song Sparrow at 
3:55; then the songs of Meadowlark, Diesissel, Bobolink, Grass- 
hopper and Savannah Sparrows before, at 4:00 A. M., the first 
Prairie Horned Lark rose in flight song. But even then he was 
invisible because of the poor light and he had beat the Bobolinks 
into the air. 

The following notes, made in the field, about mid-June, 1926, 
at Evanston, are indicative of the manner of the close of songs 
in the evening: 

7:19 P. M. Sun has set. 

7:20 P. M. The sun, from below the horizon, glints upon a 
Lark in high flight song. 

7:35 P. M. Larks are still chasing each other boisterously 
Over the meadow, calling and singing short ditties from the 
ground. 

7:51 P. M. Larks are now in song over all the meadow but 
I believe none are flight songs; too dark to be positive. 

7:56 P. M. Evening star is visible just above the point where 
the sun has set. A coolness pervades the air. 

8:00 P. M. Several Larks and a Grasshopper Sparrow are 
still in song. ie 

8:04 P. M. Many stars visible. Two Larks are still singing. 

At 8:10 P. M. The last song note was heard and that after 
a hush had fallen upon the jubilant meadow. That last note was 
the drowsy ‘‘pit-wit, wee, wee-pit’’, of the Prairie Horned Lark. 

On rare oceasions a Grasshopper Sparrow might start up from 
the beginning of slumber to give his insect trill after the Larks 
had ceased but the grand finale of the evening chorus belonged 
to the Larks beyond question, both at Evanston and at cenaen. 

Descriptions of song—The flight song of Otocoris alpestris 
praticola is a true Lark song and in its method of delivery, at 
least, has several points in common with that of the Skylark of 
Europe. It is such an astounding exhibition on the whole, that 
it is surprising that more extensive deseriptions are not to be 
found in the literature. The songs from the ground too, are 


42 Trans. Acad. Sci. of St. Louts 


worthy of note, but until now they have never been carefully 
described or transcribed fully into words. 

Wilson (1831) wrote of O. a. alpestris ‘‘They are said to sing 
well, mounting in the air in the manner of the Skylark of 
Europe .. .’’. Audubon heard this same bird in Labrador and 
gives the following description: ‘‘The male bird sings sweetly 
while on the wing, although its song is comparatively short. It 
springs from the moss or naked rock obliquely, for about forty 
yards, begins and ends its madrigal, then performs a few irregu- 
lar evolutions, and returns to the ground. There also it sings, 
but less frequently and with less fullness. Its call note is quite 
mellow and altered at times in ventriloqual manner, so different, 
as to seem like that of another species.’’ As will be shown later 
the Prairie Horned Lark sings for several minutes while in the 
air, flies much higher than forty yards and returns to the ground 
by one long straight drop. But O. a. alpestris may be quite 
different from O. a. praticola in this respect for recently (1926) 
Demille described the song of O. a. alpestris on the Gaspe penin- 
sula thus: ‘‘The male flies straight upward for fifty or a 
hundred feet as the song begins, flutters a second as he hangs 
suspended and drops suddenly to the ground with the song’s 
conclusion’’. These two descriptions are at considerable variance 
with the song of the Prairie Horned Lark as will be evident 
shortly. 

Ornithologists so intent on robbing a bird of its eggs or upon 
collecting the bird itself could scarcely be expected to listen 
attentively to the song of that bird, so it is not surprising that 
the first adequate description of the song of the Lark should 
come from the Rev. J. Hibbert Langille near the close of the 
19th century (1892). Though he spoke of ‘‘Eremophila alpes- 
tris’’ his bird was undoubtedly the Prairie Horned Lark. His 
description is, in part, as follows: ‘‘Presently I caught the 
way of the sound, and lo! its author was soaring high in the air, 
moving in short curves up, up, singing for a few minutes as it 
sailed with expanded wings before each flitting eurve upward, 
till it became a mere speck in the zenith, and finally I could 
scarcely tell whether I saw it or not. But I still heard the 
song . . . one is tempted to compare it with the squeaking of 
an ungreased wheelbarrow. ‘Quit, quit, quit, you silly rig and 
get away’, it seems to say: the first three or four syllables being 


Reproduction 43 


slowly and distinctly uttered, and the rest somewhat hurriedly 
run together . . . This ditty sweetens on occasion . . . The 
black speck unmistakably reappears, and it gradually enlarges 
as the bird approaches. Down, down it comes, meteor-like, with 
wings almost closed, until one fears it will dash out its life on 
the earth. But no, it alights in safety . . .”’ 

Hatch (1892), shortly after Langille’s account, gives the fol- 
lowing (also in part): ‘‘. . . a male flitted up from the ground 
about ten to fifteen feet into the air and about thirty yards 
directly in front of me, simultaneously bursting into song . . 
flitting, sailing, singing, he zigzagged right and left, mounting 
constantly higher and higher . . . until he entirely disappeared 
from unaided vision . . . Still the music . . . was distinctly 
audible when, after several minutes, his song suddenly ceased 
he closed his wings and, head straight downward, descended with 
the velocity of a spent bullet until, within a single yard of the 
ground . . . he opened his wings and touched the ground as 
lightly as a snowflake. . .”’ 

Before taking up accounts of other writers I should like to 
point out one or two details in these descriptions at variance 
with my observations of nearly three hundred flight bint (1) 
The Lark only occasionally seems to go higher after it begins to 
sing, most frequently it loses elevation for the song is, ordinarily, 
begun at the maximum height. (2) Only once did I observe a 
Lark begin to sing as he started to climb, as Hatch’s description 
reads. 

Hegner (1899) gives a description of the flight song similar 
to the above, adds that the Lark ‘‘arose at an angle of 45 degrees, 
in short stretches . . . Made circles 300 yards in diameter, 
sang fully five minutes.’”? Allen (1923) gives as ae 
description of the flight song. Goss (1891), Bailey (1908) and 
Chapman (1923) mention the flight song though they ~~ 
careful description. Chapman, quoting Seton, also says: “‘but 
it often utters this same song while perched on some clod or 
stone especially just before dawn and after sunset. - 

Types of song.—Though Langille’s description of the Sito 
“quit, quit, quit you silly rig and get away , 1s remarks 4 
close to one type, still he is the only writer who attemp i - 
a description and it is of but part of the song. Bailey ealls it 


44 Trans. Acad. Sci. of St. Lowis 


‘‘quaint ditty’’, Goss ‘‘twittering notes’’, Hatch ‘‘inexpressible’’ 
and Allen ‘‘like someone climbing over a wire fence’’. 

The song is indeed hard to put into words though it is far 
from ‘‘inexpressible’’. Before giving the actual song however, 
the method of delivery should first be outlined. 

Most of the singing, by far, is done from a clod or sign-post 
stage (the greatest height being a sample apartment on the area 
at Evanston), and breeding areas were rarely without a Lark 
in this performance. This was especially true after sundown, 
as Seton describes, but the first morning notes were delivered 
from the air contrary to his observation that they are from the 
ground. These surface songs are merely repetitions of the flight 
deliveries yet frequently they are not so full nor so complete. 

The urge to the flight song came frequently after the male 
had succeeded in eliminating an intruding Lark from his terri- 
tory and almost invariably, during the period of incubation, the 
male would go into flight song upon the approach of a human 
intruder. Or, if not at the first approach, he could be forced 
to do so by driving him about his territory for a time. He begins 
the ascent by a deliberate climb, step by step, by flutters and 
pauses, to his stage in the sky. This climb is deliberate, pur- 
poseful, its meaning cannot be misconstrued, though the bird 
makes no sound, as a rule, as he ascends. When satisfied with 
the altitude, he opens wide both wings and tail and as he sails 
he sings, at first deliberately, then faster and faster until the 
ending is a jumble of trills. The song may be written as, ‘‘pit- 
wit, pit-wit, pittle wittle, little, little, leeee’’. 

Each song is two seconds or less in duration and between each 
the Lark ascends with from three to four flutters of four wing- 
beats with a pause of one or two beats of time between each, 
before spreading out for the next delivery. The actual singing 
— pies less of the Lark’s time than the efforts of the bird to 
maintain the altitude, but this is more than compensated for by 
the many minutes the Lark remains in the air. One or two 
record flights lasted more than five minutes. 

If appearances do not deceive, the Lark just maintains his 
altitude after the singing begins and neither appreciably rises 
nor sinks thereafter until the finish, in the majority of cases. 

The finish of the flight song is the most spectacular event of 
all. When the song is ended the bird suddenly closes his wings, 


Reproduction 45 


turns headward to earth and drops, drops, drops for four, five 
or six seconds in certainly the most thrilling dive ever indulged 
in by living creature. The bird, when within twenty or thirty 
feet of the earth, opens his wings and alights at his starting 
place or, if it be at a distance, starts off nonchalantly to seek 
it as if it were a mere commonplace to pitch several hundred 
feet from out the sky. 

This type of song I have named the ‘‘intermittent’’ and the 
above description is its most frequent and typical rendition. It 
is subject however, to many modifications. Once or twice the 
Lark started to sing shortly after leaving the ground and con- 
tinued to sing, at intervals, on the upward climb. A few times 
the Larks failed to maintain their altitude and dropped lower 
and lower until the final dive was very short in duration. Still, 
it may be noted here, no Lark ever finished a flight song with- 
out the dive however near the earth it might be. This dive is 
reserved as a climax to the song and it seems as necessary a 
requisite as the notes themselves. 

A rarer type of song than the ‘‘intermittent’’ is now and then 
delivered in the air. To it I have given the name ‘‘recitative af 
for the Lark, during its rendition, then beats the air steadily 
with wide, slow strokes (apparently much like the Skylark in 
song), and delivers the while a vigorous, even discourse of notes. 
This song is a steady ‘‘pit-wit, wee-pit, pit-wee, wee-pit’”’. ber? 
““Yecitative’’ is frequently the prelude of the ‘‘intermittent’’ in 
flight song, lasting however but a very few seconds; and, reine 
sionally, it is given at periods other than the beginning, but it 
never occupies so much of the time as the ‘‘intermittent”’. 

If the wind is calm the bird describes large rough circles over- 
head ; if the wind is violent the bird heads into it throughout. 
The climb upward is at a considerable angle and may be fairly 
direct or describe uneven spirals. Most frequently the bird 
drops straight downward, now and then at an angle, as if slip- 
Ping down a steeply inclined roof, but nine times out of ten he 
drops directly onto a favorite song post which he must have been 
able to see at the elevation from which the drop was pists 

I have never seen a female Lark show the slightest indication 
that she was aware of a male in flight song but I have seen males 
On the ground cock their heads sidewise, fully aware, of that 
other bird overhead. But it is probable that the purpose of the 


46 Trans. Acad. Sci. of St. Louis 


song is to inform the other male of preempted territory and 
female ears are of little concern to the chorister. 

One thing of more than unusual interest was noted in respect 
to the frequency of flight songs, viz., that never were two birds 
in the air at the same time. No matter how many males were 
in the vicinity the one in flight song had exclusive privileges 
over a wide territory, undisputed, though another might go up 
as soon as the one in flight came down. Flight song territory is 
thus much larger than the surface territory ; territory boundaries 
are not vertical for any great height. 

As has been noted, singing from the ground was a fairly con- 
sistent performance through the day though perhaps a bit more 
frequent in the late afternoon. This day-time song from the 
ground was usually the ‘‘intermittent’’ type. But after sun- 
down, in June at least, the Larks had a vesper service which was 
almost exclusively ‘‘recitative’’. At that time, as the stars came 
on, they sang ‘‘pit-wit, wesspik pit-wee, wee-pit” on and on, 
minute after minute, pausing only now and then for breath or a 
moment’s intermission by singing ‘‘pittle, wittle, little lee’’. 

Quantitative studies of song.—The height at which the flight 
song is delivered has been a matter of considerable speculation 
by several writers. Thus Eaton (1912) says ‘‘reaching a height 
of several hundred feet’’, Townsend (1920) ‘‘sometimes out of 
sight in the low-flying clouds’’, Merrill (1888), in describing 
the song of O. a. strigata, writes that, ‘‘The height at which they 
fly is so great that often they may be seen to poise and then to 
resume their circling flight before any sound reaches the ob- 
server.’’ This last estimation making the height between one- 
thousand and two-thousand feet, for the ‘‘intermittent’’ song oF 
length of time of sail in praticola is just short of two seconds. 
Sound travels 1090 feet per second. This is, of course, an impos- 
sibility for at 1000 feet the Lark is invisible even to eight-power 
ag Patch, Bailey and others mention that they fly out 
0. < 


I attempted to secure an accurate measure of the height at 
which the song was delivered in order to settle the matter defin- 
itely. Three methods were employed: (1) by timing the drop 
with a stop-watch, (2) by using a large quadrant to secure a tri- 
angulation, (3) by measuring the length of the bird in the ait 


Reproduction 47 


with the aid of a scale in my binocular. Of these three the last 
gave the most nearly accurate and most extensive results. 

The stop-watch method must take into consideration too many 
elements to be reliable. Thus, though the rate at which an 
object will fall in a vacuum is definite enough, the Lark is not 
in a vacuum. Furthermore it often has fallen considerably in 
altitude while singing before beginning the final drop and, fre- 
quently, it does not always fall directly down. However, a good 
many timings of the drop were made, the average of the whole 
being about five seconds. The bird thus, if in a vacuum, would 
have fallen, on the average, 496 feet. This, at least, gives an 
idea of the height but is greatly in error when air-friction and 
the lowering of altitude before the drop are considered. 

With one person to sight along the movable arm of a large 
levelled quadrant to secure the angle of a Lark in the air (but 
not directly overhead) and another to get directly beneath the 
Singing bird a triangulation could be secured. Thus, on one 
oceasion, this angle to the bird in the air plus the horizontal 
distance away were obtained. This is a simple trigonometric 
problem in which two angles and an included side are known. 
The result was about 350 feet. However this method is faulty, 
not in technique, but in execution. In the first place, two people 
are necessary to execute it; secondly, it is difficult to get to 
coincide the obtained angle and the horizontal distance at the 
Same time for the bird is constantly moving; lastly, a bird at 
maximum height cannot always be found with the unaided eye. 

With the binocular scale and the known length of the bird 
(about 8 inches or 19.0 cm.) estimation of height becomes rela- 
tively simple and accurate. It is necessary merely to find the 
value of a unit of the scale for the length of the bird at a known 
distance. The value of the scale unit for an object of known 
length at any distance can then be calculated from this known 
basis. It is merely a simple task of calibration. 

Thus, by using an old military binocular with an ocular scale, 
accurate measurements of the height of 25 song flights were ob- 
tained. The lowest noted was 270 feet, the highest 810 feet. 
The majority were delivered at about 540 feet. The average, 
Properly weighted, was 464.4 feet. 

Visibility of the Lark in flight song—The question of 
whether or not the Lark goes out of sight depends upon many 


48 Trans. Acad. Sci. of St. Louis 


things: eyes, light, clouds, time of day. In morning or evening, 
on clear days, it was always possible to find or to follow the 
bird with the unaided eye for the light, low in east or west, 
then does not blind the eyes and aids by giving the bird a 
shadow on one side or the other. With the sun nearly overhead 
the bird goes out of sight quickly for the light blinds and the 
size of the bird is not accentuated by a side shadow. With clouds 
above, of any description, a singing Lark can always be found 
for then it is a moving silhouette nearly always sharply outlined 
against its background. Under any circumstances the singing 
bird was always visible to an eight-power binocular if it were 
followed as it ascended so that its position could be ascertained. 

The songs, whose heights were obtained, were listed by months 
to see if the bird averaged higher or lower in one part of the 
season than in another. Nothing is evident, however, in the 
material at hand for, though the record height was in March, 
songs nearly as high occurred in June. Differences in heights 
then were matters of individual variation or the result of 
weather conditions. 


Duration of the flight songs.—Thirty-two songs were timed 
with a watch from the beginning of the ascent to the final drop. 
One minute was the shortest of which there were four; five 
minutes was the longest of which there were five. The average 
for all is 2.34 minutes. 


es Number of songs per minute during the flight.—Since the 

recitative’’ is a continuous jargon of notes its repetitions could 
not be timed. Its duration in a flight was rarely more than five 
seconds. The ‘‘intermittents’’, that is, the songs given while the 
bird is sailing, are repeated at remarkably regular intervals. 
The average number of these per minute, in an extensive series 
of counts, is 11.9. 


Relation of the singing male to the incubating female.— 
Mouseley (1919) gives the distance from the nest at which 
the male Lark sings (when on the ground), at 32, 34 and 21 
yards for three different nests. His figures are a bit too con- 
Servative, even for averages, for the Larks at Evanston or at 
Ithaca. By referring to Table 15 it will be noted that the male, 
in this case, preferred a song post at 50 yards, sang as far as 
100 yards from the nest, averaged 38.66 yards. Ithaca birds, 


Reproduction 


150 yards. 


49 


with larger territories, sang even farther away, frequently at 


Summary.—The song of the Prairie Horned Lark is, all in 
all, one of the most remarkable activities in the bird world. 
With a season from January to July, an optimum in May, a 

8:00 P. M. (in June), a flight 


daily period from 4:00 A. M. to 8: 
song with an average height near 500 feet, two types of delivery 
on the ground or in the air, and an evening’s vesper that out- 


lasts all others—it becomes an exhibition above challenge. 


=a 


50 yards scale 


Fc! Se cole 
pa fae 
: 
_-fmound s 
or” = 
P . ‘ 
a : 2 e 
Z % 
‘4 Pri 
4 
A 
i 6 
ul 
' 
' 
‘ 
‘ 
' 
' 
’ 
t 
: 
‘4 
———_—_" 
ieee - 
m; 
7 Streetway 
Soe 
a 
. 
. 
— 
ee ae 


TF 


ie, 
pea all 
See eee 
~~ 
peda 


: Bong post 

of nearest 

Lark neigh- 
bor 


* 
~~ 
a Potead katel 


. ~~son osts. 
suber’ indicate 
rder of prefer- 


————— 


ence. 
territory boundary 


orned Lark, Feb. 7, 1926, at 
date. 


Fig. 1. The territory of a male Prairie H A 
Evanston, Ill., as marked out by the song posts of tha 


50 Trans. Acad. Sci. of St. Louis 


Nesting Territories 

Since the publication of Howard’s (1920) now famous book 
on ‘‘Territory in Bird Life’’ no extensive study of a bird is 
complete without considering this important phase. 

Evanston.—The earliest delimiting of territory at Evanston 
was noted February 7, 1926. A male bird, on that date, marked 
out the area as shown in Fig. 1. Only on one border did he 
come into contact with another male and there considerable 
fighting occurred. From a territory such as this a male bird 
will not leave no matter how consistently one annoys him by 
driving him from place to place. His usual relief is to go up 
into flight song. A female was noted with him from time to 
time though she did not persist in the territory. Several other 
birds on the same area, this date, had established song posts and 
territory boundaries. 

There was no method of knowing, at Evanston, whether the 
same territory was retained throughout several nestings because 
of the large number of birds on the area and the consequent 
confusing of individuals. Each large snow storm would destroy 
song posts and disrupt territories and data are not at hand to 
show whether the former territories were returned to when con- 
ditions were favorable, though such is probably the case since it 
proved so at Ithaca. The chief single item in modifying terri- 
tories, once they were established, was the growth of vegetation 
and this in June and July would narrow them down, pinch them 
up or cause their abandonment entirely. 

At Ithaca I forced a male to mark his territory for the 
first time on March 13, though song posts had been established 
some time previously. This was territory ‘‘A’’ (see figure 2). 
Subsequently territories ‘‘B’’ and ‘‘C”’ were plotted as noted 
in figure 2. Of interest is the fact that the territory which the 
male marks when forcibly driven from song post to song post is 
somewhat smaller than that which he will delimit if allowed to 
go voluntarily from place to place. The reverse of this, one 
would think to be the case. Of course not all portions of the 
area are occupied with the same frequency, in fact the bird goes 
but rarely to the remote boundaries. Those regions in juxtaposi- 
tion to the neighboring Lark are, as one might well suppose, the 
positions most frequented, for it is here that limits of the are@ 
must be most rigorously guard 


Reproduction 


4s 
buckwheat /s \ hay meadow // 
As oe en nee 
ar See if Y { road 
Araya | Cc 3 
cece garden | B hay meadow 
\ j 
| 
~ 
meh Cte ey 9 neste 
1 LY 
iifrthy | | 
0 
| 
! 
| 
| moe 
weed patch N\ 4 
| y \ 
i \ Ks 
a \ \ % fall wheat ; } 
wu wa \ cs , 
een Pegi °o 
ae oa "Manet J 
=< ~ zy 
a ee ny, ip ‘A % 4 
if my a uf 4f 
! = * ~*~ > 
1é § pF 5S 
j © fallwheat 3 = \ 
Waste ground H r - z \ Ny 
Weed patches Vf jz 3 Ny | 
ty y a sh jv 
: =! 
: ZV 
% 97 x 
etn us 
a 


200 yards scale 


Fig. 2. The territories of Prairie Horned Larks A, B and C in March 
and April at Ithaca, New York. 
Boundaries of territories seemed to be limited, in a general 


way, only by the size of the suitable area and by the number of 
males attempting to possess it. Thus, at Evanston, where the 


52 Trans. Acad. Sci. of St. Louis 


number was higher, proportionately, than at Ithaca, the average 
territory was only about 100 yards in diameter whereas at Ithaca 
they extended out to lengths of 300 yards and breadths of 200 
yards in some cases. The territory of pair ‘‘D’’, a short dis- 
tance from ‘‘A’’, ‘‘B’’, and ‘‘C’’, was a field of plowing just 
six acres in area which pair ‘‘D’’ called their own exclusively. 

But though some boundaries might be established by the mar- 
gin of unsuitable territory there was a limit even where suitable 
ground still persisted. Thus the old stubble field, which was 
later plowed and sowed, extending off to the northwest from 
territory ‘‘C”, was eminently suited for Larks yet the ‘‘C”’ 
male was never seen farther than the boundary noted in figure 2. 

That invisible boundary, that the male birds put up between 
themselves where their territories coincided, was of the greatest 
interest. The boundary between ‘‘A’’ and ‘‘B’’, ‘‘C’’ and 
‘*A’’ was a ridge, extending into a fair hill on the east. It is 
not strange that a natural marker, such as this, should be used 
to delimit the area. But the line that was laid down between 
“‘B”’ and ‘“‘C”’ was over a perfectly smooth stretch of ground 
with no natural indications of any kind. Yet these two birds 
recognized it within twenty or thirty feet for a length of more 
than 100 yards. And here they posted themselves for the greater 
amount of time, to see that the other respected that invisible, 
but to them, quite definite boundary. 

_ History of territories in subsequent nestings—The observa- 
tions at Ithaca followed Larks ‘‘A’’, ‘‘B’’ and ‘‘C” throughout 
the season from March to late June and through a number of 
nestings (see Tables 4, 6, 8, 9, 12, 13, 24, ete.). It is apparent 
that, except for one influence, the territories would have Tre- 
mained unmodified from first to last. That modifying influence 
was vegetation, here tall wheat. Thus territory ‘‘A’’, entirely 
within the fall wheat, was completely abandoned at the close of 
the second nesting in May. Territory ‘‘B’’, partly on the garden 
and partly on the fall wheat, was reduced in May on the east 
in the fall wheat portion, to little strips running up and down 
from the ditch there which had been washed bare of seed in the 
fall rains (Fig. 3). These areas, in June, were finally no longer 
tenable and the ‘‘B”’ pair was forced to a territory on the garden 
less than 50 yards wide (see Fig. 4). The territory of ‘‘C”’ 
was shortened to the ditch on the south but otherwise remained 


Reproduction 


m the ‘‘B’’.**G’? 


essentially unaltered. Now, if ever, should have come a change 
h boun 


oats 


? was reduced to straightened 
quarters; ‘‘C’’ still roamed over a region more than twice as 


wide. I noticed a little more fighting now than usual but, with the 
exception of a possible shift of a meager twenty yards or so that 
same invisible, almost invincible boundary, erected in the storms 
of March, still held, unaltered, almost unquestioned 


ae hay meadow 
ee ee 
‘ 
%Y “ AS | 
yyw 1 B 
{ \ 
oats | garden \ garden 
\ \ 
eae ct oe ee 
road 7 > 
ETT? | | | =< 
'¢ s 
\ 
Oo garde 
garden ||old 
Toad 1 By A 
weed patches vote 4 a f 
se \ ane ty 
ditch ~~~’ Bs. Ni 
ay 
\ ~ aura. § ae 
fall wheat VJ e us mK 
SS a eee Sig f L2 se t 4 
r Vommnutrig 
Zsv, 19 
sti zs %| 1 
~ Wn, ge 6% ty 
= % 
= fall wheat Me ‘ 
= = hill 
Wp 
¥¥) = 
Waste ground and 
weeds 


ae 


4) \ 
“Ny, 1 sh ww wilt 


fall wheat 


Loe 
f ! wo 


a 


SOO yeree O0OTe 


g. 3. The territories of Prairie Horned Larks B and C in late May 
at Ithaca, New York. 


weed patches 


= 


54 Trans. Acad. Sci. of St. Louis 


The south portions of the gardens had been in fall rye, but 
small areas of this were plowed under from time to time and 
thus exposed bare ground so that parts of this region were occu- 
pied throughout. The plant-stuff under cultivation, up to July, 
did not so cover the ground but that the gardens remained, until 
that time, quite suitable. (Incidentally, on the bare ground of 
this garden a flock of twenty to thirty Larks was seen Aug. 8, 

1927.) 


hay meadow My 
\ 


“ 
> 

x 

s 


hay meadow 


o~ nests 


fall wheat 
a 
weed patches a } 
fall wheat Th 
= een) TLL TTT %. ' 
ri MO An ay, ' 
ag gy z2%},! 
s “try, == S : 
§ %, so ay 
; : : 
$ = hill { 
5 fall wheat = Sy 


7 YY : 


CTT a 


apace eR EEE 
200 yards scale 
The territo 
haca, New York, 


ries of Prairie Horned Larks B 
° 


an 


: 
a C in June at 


Reproduction Bh 


Feeding in relation to nesting territories——The males were 
on their areas so religiously that most of their feeding must have 
been done there too. However, now and then, one would be 
seen to fly up and out of sight as if intent on a considerable 
journey. These journeys at Ithaca were to the northeast and 
to the south. The attraction to the northeast was not ascertained 
but to the south was a stubble field with patches of Setaria. 
This was, apparently, a neutral feeding territory for several 
Larks. All observed feedings of the female were also within the 
territories at Ithaca, though at Evanston the female would go 
out considerable distances, clearly outside the nesting territory, 
though she gathered much food, as well, within the immediate 
Vicinity of the nest. Incidentally, it should be noted, the female 
would mark out the territory if she were driven from place to 
place, though, being quiet and less obvious than the male, it was 
difficult to follow her for any length of time. 

Nests were placed, of course, in these territories and placed 
with little regard to the center of the areas. ‘‘B:’’, for instance, 
was on the southeast margin whereas ‘‘Bs’’ was on the extreme 
west. For complete data of nestings see Table 9. It is probably 
unnecessary to say that, though the male established the bounds 
of the territory, the female chose the nest site. Finally, it 
should be noted, that in one or two cases at least, the Larks were 
mated before territory bounds were definitely established though 
the reverse seemed true of others. 

Summary of nesting territories—Territories, at Ithaca and 
probably also at Evanston, were established very early in the 
spring and maintained with the same boundaries,* wherever 
possible, throughout the breeding season. Any change they 
were suffered to undergo came about with that one factor which 
the Prairie Horned Lark cannot endure, the advent of heavy 
vegetation. 

Courtship 

Song, the establishment of territory, battles at the boundaries, 
all these are part of courtship and have been discussed in pre- 
ceding paragraphs. A few more items regarding fighting of 


liar in 
As will be noted later the fourth eee of yg “B” was — vill 
tha igm other three. Its 0 aerenee. in 
and fhe gp ns 2 the tas cervitony in 1927 gobpend <6 clinch the identity - 
e territory (though the birds e to own "T1028, he tells of 
letter ‘Fecelved from M, D, Pirnie at Ithaca, dated A cr pind 12, 
t in this same territory with the same type of pind 


56 Trans. Acad. Sci. of St. Louis 


males, and females, with a description of the strutting male will 
close this phase of reproduction. 

Fighting —As has been pointed out, territories are estate 
lished very early in the season and after that time all fighting 
between males occurs along those boundaries of their territories 
which are in juxtaposition with those of a neighboring Lark. 
Fighting, prior to the establishment of territories, is promiscu- 
ous. All quarrelling takes place in the air. Never once did I 
see a battle on the ground, though Sutton (1927, p. 133) men- 
tions ‘‘tussles on the ground’’. At the boundary dividing 
opposed territories the two males will most frequently be found. 
Here they remain together, seemingly most friendly and amiable 
except for an occasional sharp call note or a little strut with 
horns up, tails spread, wings adroop. Now and then they will 
approach each other in this attitude and peck away at the 
ground, furiously, like two cock roosters in an intermission of 
battle. But if, for any reason, one male attempts to fly, or if 
an intruder flushes both of them, then up they go, dash against 
each other, tumble over and over, an animated bundle of strug- 
gling feathers. Having indulged in wing to wing combat for 4 
moment they finish off with a most curious game of tit for tat: 
one chases the other for a few feet in the air, invades thus the 
fleeing one’s territory, the pursued promptly turns pursuer and 
in turn gets into his neighbor’s territory, when the game is again 
reversed. So back and forth they go, one now chasing, next 
being chased and if the end of the game depended for its con- 
clusion that neither should be upon the kingdom of the other then 
the ending would never be reached. Finally, however, one tires 
and goes off at a tangent while the apparent victor drops to 4 
song post and there sings his song of triumph. But not for long, 
for soon the other is back at the boundary and friendly enemies 
they become again. For all this activity from March to June, 
so far as I can see, no harm is ever done. 

Reactions of male and female Larks to each other.—The 
female is, at nearly all times, most curiously indifferent to the — 
male. Only once did I see her flutter and crouch before him 
as one observes the female House Sparrow do so frequently: 
The female Lark thus has no courting maneuvers, though Sutton 
(1927) remarks a thing the writer has never observed in spite 
of intense observations, namely that the female answers the 


Reproduction 57 


male’s full song ‘‘with a bright snatch of her own.’’ The male, 
though, stays with her assiduously during the nest-building and 
egg-laying and may be observed frequently strutting with wings 
dropped, tail spread and horns up. Furthermore he has a little 
note of greeting that he reserves for her. It sounds like ‘‘eheck’’ 
or ‘‘cheek’’. On only one occasion did I see a female become 
pugnacious toward another Lark. In this instance she was 
guarding a youngster just from the nest. A neighboring male, 
in curiosity over this activity, invaded her territory to investi- 
gate, forthwith she got up and had at him with a fury well 
worthy of an Amazon. But, inconsistently, a moment later 
she fled before him as he made a second sally. 

In connection with this study of territories and courtship I 
should like, in conclusion, to make a few comparisons between 
these observations and those of others. They show, most clearly, 
the whole change in attitude toward the activities of birds in 
courtship and nesting since the publication of Howard’s (1920) 
famous studies of ‘‘Territories in Bird Life.’’ Thus Jones 
(1892), in one of the most anthropomorphic descriptions en- 
countered, says of the Larks that if a second suitor appears on 
the scene and the female shows ‘‘no preference” then the issue 
rests upon a battle which is short and decisive. She accepts 
the suitor of the previous year unless he has been killed (Jones 
does not say how he knew this) otherwise two young fellows 
vie with each other. The female usually shows a preference 
otherwise a battle follows. In any case battle is the ‘‘court of 
final appeal.’’ If a female loses a mate she at once ‘‘seeks 
another and always finds him.’’ And many more similar and 
untenable comments. Though, on the whole, the account of 
Harris (in Bendire, 1895) is the most extensive and thorough 
of any in the literature, some of his observations too are not 
now, with our present knowledge of the significance of territories, 
tenable. He says, for instance, after giving an admirable ac- 
count of the manner in which Larks fight, when “suitors for the 
same female’’: ‘‘The victorious suitor then quickly returns to 
his coveted mate and struts before her with raised ear tufts and 
trailing wings, very much in the same manner as the English 
Sparrow.’’ Lastly, and scarcely justifiable in the light of mod- 
ern research, Sutton (1927) writes, ‘‘I believe the birds are 
essentially pacific and that males, rather than have a prolonged 


58 Trans. Acad. Sci. of St. Louis 


fight over a certain female, give a chosen one and search in to 
elsewhere for a mate.’’ But it is evident now that the fighting 
is not for a female but for the defense of a boundary, that fight- 
ing may be most vigorous before a female arrives or after she 
is incubating and that, in the case of the Lark, very little or 
no fighting occurs during courtship, nest-building or egg-laying 
for then the male stays within the bounds of an established ter- 
ritory and most sedulously attends his mate. 


The Nesting 


Season of nesting.—One would expect the dates of nests and 
the dates of song to correspond, and so they do, roughly. Song 
begins in late January, nests, as a rule, in March; song ceases 
in early July but nesting may not cease until August ap- 
proaches. 

The beginning of songs in January, in the depth of winter, 
in a setting of barren, wind-swept, unprotected plains and hills 
is not more incongruous than an incubating Lark sitting on her 
eggs in the sleet and snow of March squalls. 

Four records of February nests have been found in the lit- 
erature: The first of these is that of Linden (Forest and 
Stream XIV, 489) who found ‘‘Eremophila cornuta’’ with half 
fledged young the middle of February at Buffalo, New York. 
This article has not been available to the writer and is given 
here on the authority of the statement in the Bulletin of the 
Nuttall Ornithological Club, 5, 1881, 50. The second is that of 
Nelson (no date but circa 1880), who, writing of birds of north- 
eastern Illinois says ‘‘Sometimes the last of February.’’ The 
third is of a nest with eggs in February at Plymouth, Michigan, 
found by Mr. J. B. Purdy and reported by Cook (1893). The 
fourth February nest is mentioned in Bendire (1895), who 
writes of a nest ‘‘found in the vicinity of Milwaukee, Wisconsin, 
Feburary 23.’’ It is quite possible that February nests are not 
uncommon for the birds frequently in February, in my OWD 
observations, presented all the activities of nesting. Sutton 
(1917), Jones (1910), Barnes (1890) are a few among the many 
writers who mention the ‘‘late winter’’ or February mating a¢- 
tivities of this Lark. Yet nests, prior to the beginning of in- 
cubation, are next to impossible to find, as will be shown later, 


inches 


Reproduction 


at 8.00 P, M.) 


—— 
_——_ 
— 
See 
i 
-—— 
-. 


a 
- 
ae ae 


V1. snow (en ground 


! 


a 
-—. 
- 
- 


Piret eggs laid (nests no. 1 and 2) 


Nest building began 


or 
© 


27 28 30 


24 26 2 


t ' , qT 


tT 


qT 


9 £0 it 193 49 144 15 16 1718 19 


On ie 


i 
' 
a ° a - sa 


Fig. 5. Mean and minimum — temperatures and snow on the 


ground at 7:00 P. M., 


at Evanston, Ill, with a 


6, 


; or rch, 192 
tabulation of be breeding aaieition of the Prairie Horned Lark 
during the mon 


60 Trans. Acad. Sci. of St. Louis 


and it would be rare for periods of mildness in February to be 
sufficiently extensive to allow nesting to proceed to the point of 
incubation. Still it is probable that February nestings are not 
numerous for the ovaries of two females, one of which was 
mated, collected March 11 at Ithaca, were still several days from 
a period of maturing eggs, though the testes of males, col- 
lected the same date, were exceptionally large. But if Feb- 
ruary nests are the exception March nests are the rule from 
Kansas to Manitoba, from Manitoba to the Atlantic. 

The following is an incomplete summary of March nestings 
by States: Kansas City, Missouri, March 12 (Harris, 1922) ; 
eastern Nebraska, late March (Bruner, Wolcott, Swenk, 1904) ; 
Marathon, Iowa, March 29 (Crone 1889) ; Manitoba, middle of 
March (Criddle, 1917) ; Quincy, Illinois, March 28, three nests 
(Poling, 1889) ; Champaign County, Illinois, March 15, March 
31 (Hess, 1910) ; Michigan, before middle of March (Barrows, 
1912) ; Ohio, last week of March (Jones, 1910) ; Ontario, March 
28 (Eifrig 1911); New York, young able to fly April 7, 1878 
(Langille, 1892) ; New York, late March (Bendire, 1895) ; New 
York, well started in incubation March 11 (Eaton, 1914); 
Pennsylvania, average March 25, earliest March 18 (Harlow 
1918). 

Before taking up the discussion of such a remarkable phe- 
nomenon as a Passerine nest in March, the few references be- 
fore me pertaining to the last nests of the season will be given: 
Nebraska, ‘‘well into July’’ (Bruner, Wolcott and Swenk, 
1904) ; Manitoba, July 14, eggs, ‘‘males still singing every- 
where’’ (Criddle, 1920) ; Illinois, July 6 (Hess, 1910) ; Mich- 
igan, June 19 (Barrows, 1912). At Evanston, Illinois, the 
earliest nests were started, apparently, about March 21 in 1926, 
the last nest was destroyed by an unknown external cause 
July 12. If it had been successful it would have persisted to 
about July 20. Nest building began at Ithaca about March 11 
: 1927, the last nesting would have persisted to June 28 had 

it not been disrupted by experimentation. 

Explanations of March nests.—To show why a bird nests 
when it does has been the endeavor of many an ornithologist 
theoretically inclined. Food, necessities of the nesting site, 
physiology cycle, distance of migration, have all been advan 
© explain the season of nesting of various species. No 


Reproduction 61 


nim 


er Se Or ee Se ae 


¢ 
3 
Set complete (4 eggs), incubation n began, (nest no 
| ‘ Set complete (5 ens ine ubation began, eo no-43) 
Pirpt=egg laid (nest no. 14) 
First egg laid (nest no. 13) 
Nest building began (nests no. 13,14) 
First egg leid (nest no. 11,12) 
Set completed (nest no. 3) 
First <8 | laid (nests no. lg 
at ion Soin (ne . 3) 
First es a (nests no. cae ) 
= First egg laid (nest no.9) 
a 
g st building began (nesta no.3,4,5,6/7 tae 
o 
ee 
3 
i é 
Fe a 
2 i 
+) tee 
£ ee 
3 rhea 
~ pat ad 
: eS 
a 
= 
s >... 
Be ee 
Ee oe 
7 o @ te i 2 od _ > = 
ee ee 1 ‘ 4 
tT ' 0 o 
s 8 S: 8 88 3 


Fig. 6. Mean and minimum daily gi pra s and snow on the 

ground at 7:00 P. M., for April, 1926, t Evanston, Ill, with a 

tabulation of the breeding peach re of st Prairie Horned Lark 
during the month, 


820 21 2225 2425 26 2t 28 & sd 


7 181 


7 


14 1516 1 


10 1112 138 


ays 


a 


62 Trans. Acad. Sci. of St. Louis 


word has been said in any given case. This problem still re- 
mains one of the greatest, most fascinating enigmas of ornithol- 
ogy. Nor is there an adequate explanation for a March nest 
in the case of Otocoris alpestris praticola. If the bird nested in 
March only then the case would be clear for the argument that 
the barren nesting site is required—but it finds barrens into 
July; if it were true that greater food opportunity existed in 
March and not in other months there would be a good cause for 
nests at that season—but many young die of starvation even in 
April (see tables 22,23) ; the argument that the season is early 
because the bird arrives early is good but so does the Gold- 
finch and the Waxwing, and they delay to late June or early 
July before starting; the physiological cycle is at the bottom of 
it but why such a cycle? Why nestings that are snowed under 
in March when the season extends to July? 

Before going further with an attempt to explain this phe- 
nomenon I wish to present a study of the possibilities of suc- 
cess of March nests in two localities of their range. By a strange 
coincidence the March nests at both Illinois in 1926, and at Ithaca 
in 1927, were destroyed by a heavy snow late in that month 
and early in April. From these two observations I was led to 
believe that the majority of March nests, at these latitudes, 
would be unsuccessful. To prove or disprove this I obtained 
weather summaries running back to 1910 for the Chicago re- 
gion, and to 1916 for the Ithaca region. 

Weather control of March and April nests.—TFirst, however, 
by a study of known March and April nestings, it was possible 
to learn the temperature and duration of that temperature 
that was required before a nest would be started. This led 
to a very remarkable discovery( see Figures 5, 6, 7, 8) namely, 
that the initiatory temperatures was a mean somewhere be- 
tween 40 and 45 degrees Fahrenheit and that with one exception 
it extended over a period of more than two days. The excep- 
tion was an April nesting which was begun the first day the 
mean was above 40 degrees F., but even here two birds, one of 
which was known to have nested in March, did not begin their 
renesting until the second warm peak when the mean was again 
above 40 degrees F’. and for several days in succession. Knowing, 
thus, what conditions are necessary to initiate a March nest, it 
ey became necessary to consider what conditions will destroy 


Reproduction 


Set 


Nest, building began (nest B1) 


Fig. 7. Mean and minimum daily tempera 
Ithaca, New York, with a tabulation 0 
Prairie Horned Lark during the mon 


o 
eo 


(cessnow(on ground et 7.00 P, M.) 
T \ A 
© 26 27 28 29 30 31 


4 
’ 
’ 


A 


9 2D 21 2223 B42 


18 19 


completed, incubation began 


6 17 


1 


First egg laid 


eT Ce Cen hk eh et 


4 


3 

2 

ac 
ee Ee 


tures for March, 1927, at 


f breeding activities of the 


64 Trans. Acad. Sci. of St. Louis 


It is probable that, once a nest is started, subsequent cold 
weather will not inhibit it—the physiological processses are not 
checked. To substantiate this observe the weather of March, 
1927, that intervened between the initiation of the nest about 
March 11 and its ultimate destruction at the end, or, again note 
that the nest begun April 6, 1927 (Fig. 8) passed through 
several nights with temperatures much below freezing immedi- 
ately thereafter but the clutch was completed in record time 
(indeed the eggs must have survived this cold uncovered). If, 
then, cold weather alone will not destroy March nests their 
meteorological enemy is restricted to snow. Without a doubt 
the female bird will incubate through a slight snow without re- 
linquishing her eggs. Note that a slight snow fell March 26 
(Fig. 7, also Plate VII, Figures 2), but the nests were not 
abandoned because of this. Many writers have found Lark 
nests in the snow and Langille goes so far as to say that a 
Horned Lark flushed out from under ‘‘three or four inches’’ of 
snow, April 6, 1880 (Langille, 1892), but it is probable that 
the bird would not have remained under the snow for more 
than a few hours. The snows of early April 1926 and 1927 
destroyed all nests and there is no doubt that any snow of 
three inches or more that lasts two or three days will cause 
the destruction of nests. Bendire (1895) in quoting Harris, 
says: ‘‘The weather during the latter part of March (in 
western New York) is often very pleasant and warm, only to 
be followed by a heavy fall of snow about April 1, when a good 
many unfinished nests and incomplete sets of eggs are snowed 
under and deserted by the owners; in fact, only a few birds 
will cling to their nests under these circumstances, as I have 
found many abandoned ones in different seasons.’’ 

Now, having concluded that nests would be begun in March 
whenever two or more days of a mean temperature of 40-49 
degrees F. occurred, and that they would be destroyed by 
snow of three or more inches lasting two or more days, the sue 
cess of hypothetical nesting at Chicago and Evanston coul 
be tabulated from the weather summaries. The only reco 
for snow on the ground in these summaries is at 8:00 P. M. at 
Ithaca or 7:00 P. M. at Chicago and this is exceedingly co 


‘servative as far as the total amount of snow is concerned. The = 


result of this tabulation is shown in tables 1 and 2. The interest- 


Reproduction 65 


Z 2 
4 t 

rc] 
3 
Se 
ie 
o 
ation began, eet complete (Ci jg Ke 

began, set cozplete,(A2 nest s 
began, =p ’ A peo 4 
+3 
42 nest); fourth egg hatched (B2 nest) Lg 
laid (C1 nest); 3 eggs hatehed (B2 nest) Ls 
a) 
+e 
Nest building began (A2 snd C1 nests) [2 
Pe 
ot 
i 
=) 
”“ 
-S 
e 
| <a 
— 
Set complete (4 eggs) Hrs 
Incubation began (3 eggs) -2 
_a 
First egg laid ED 
Sad 
Nest building began (B2 nest) -_ 
z a es 
gs a 

38 coaneet 

~e Pe a 
5 * Poi =) 
2 ? ---flest Bi and Al 

° -~ destroyed by snow Kel 

} * © & ° r) + ° - j) 
T Ls ¥ ’ is ba st 
* 8 eo 3 2 8 = 3 


Fig. 8. Mean and minimum daily temperatures and snow on the 
ground at 8:00 P. M., for April, 1927, at Ithaca, New York, with a 
tabulation of breeding activities of the Prairie Horned Lark 

nth, 


uring the mo 


66 Trans. Acad. Sci. of St. Louis 


ing thing to be noted is first, the surprisingly large number of 
opportunities for successful nesting there are in March and, 
secondly, the fact that nestings in northern Illinois have a 


greater chance than at Ithaca, New York. 
But the reason for March nests remains still incompletely 
explained. The habit was probably acquired very early and 


TABLE 1 


Hypothetical are ae — of the Prairie Horned Lark with the probable 
with regard to snow, in the Chicago, IIl., region, for 
the years 1910-1927 paces 1924). 


ultimat 


e success or fai 


Deep aximum Amount 
Year Sac aarag Nesting Snow on Ground of Snow on Result of, March 
eriods in March aes to Ground at 7 P.M. Nesting 
1910 2 to 6, 11 to 13, 
{ 18 to 31 } None. Successful 
1911 8 to 12, 19 to 22 
{ 24 to 27 } March 27 to April2.| 2in. April 2...... Successful? 
1912 | Snow on ground throjughout month. 
1913 12 to 14, 18 to 20, 
{ 23 to 24, 29 to 31 \ Ware 2h ee ees 2.2 in. March 21...} Successful? 
1914 | 14 to 16, 24to31 | None Successful 
1915 | 13 to14,23to25 | None Successful 
1916 12 to 18, 24 to 26, 
{ 29 to 31 \ PAMOR Pe ee ee: 2.6 in. March 22...| Successful? 
1917 | 10to11,20to31 | None Successful 
1918 (i to 5, 8 to 9, 11 to 
12: 171022, 29to31 None Successful 
1919 | 15 to 20,24to30 | None Successful 
1920 9 to 11, 14 to 16, 
{ 21 to 31 } April 4 to7........ 6.1 in. April 4..... Failure 
1921 ae 1 to 2, 5 to 21, 24 
o 27, 30 to 31 None Successful 
1922 5 to 6, 9 to 16, 
{ 27 to 28 } Marcel 3160020055, 1.1 in. March 31...| Successful 
1923 1 to 4, 21 to 22 March 18 to 19... 1.3 in. March 19... Baccemtel ae as 
ne a 
only) 
1925 | 6to10,16to31 | None.. Successful 
1926 19 to 25 March 26 to April 6.} 9.9 in. April 3..... Failure 
1927 | 8to19,25to31 | None Successful 
¥Niot leca +h + ‘ a Sth joovehn F. 


NOTE: All dates are nee: fetlosive: 


umber of years of ieilures due to snow: 2 


of years of problematical success: 4 


Reproduction 67 


it has been carried eastward and northward with the recent 
extension of range into regions where it is obviously a greater 
incongruity than in the earlier home. For even in northern 
Illinois March nests are far more successful than in south central 
New York and the discrepancy would be greater between east- 
ern Kansas and Manitoba. The question, at this time, must 
rest here with the conclusion that the origin of March nestings 
is not fully known but may have been developed as species- 


TABLE 2 
Hypothetical March er of the Prairie Horned Lark with the hn 
ultimate success or failure with regard to snow, in the Ithaca, N. Y., 
for the years 1916 to 1927, 


Year Possible* Nesting Pe npr iroend cee tigen an | Result of March 
Periods in March ie oo to Ground at 8 P.M. Nesting 

1916 25 to 31 None Successful 

1917 23 to 31 None Successful 

1918 |12to14and 17 to 22| April 9 to13....... 10 in. April 12.....| Failure 

1919 | 17 to 18 and 25 to 26| March 27 to April1.| 5in. March 28 to 29| Failure 

1920 22 to 31 None Successful 

te { — eh ee } None Successful 

1922 13 to 15 March 30 to 31.....] 2 in. March 30....| Successful? 

1923 21 to 23 None Successful 

1924 28 to 30 April} to 8.20.5. 7 in. April 2... Failure 

— { =a e ay st } March 28 to 29.....| 2.5 in. March 29...| Successful? 

1926 None _— nape! Dr tn “ak penal = degree|s F. and snow on 

1927 11 to 14,18 to 19 | Aprill to3........ 4m; April 1... << Failure 


*Not less than two days ce a mean temperature above 40 degrees F. 
NOTE: All dates are inclusi 
Sum: 


: Numbe si ears considered: 1 
Ni woe oe of years c in which Maren — _— possible: 11 


necessity in some earlier home where such nests were sufficiently 
successful to have been maintained ; and now such nestings have 
been carried to regions where they may, eventually, be elimi- 
nated through natural selection. 

Finally, before leaving this fascinating subject, it should be 
noted that praticola seems to be unique among all the Horned 


68 Trans. Acad. Sci. of St. Louis 


Lark subspecies in this habit of early nesting. I have found no 
evidence, in the literature, that even such southern forms as 
giraudi or chrysolaema nest in March and alpestris does not begin 
until June in Labrador. Lastly Criddle (1917) notes that enthy- 
mia breeding in the same region with praticola at Aweme, Mani- 
toba, does not begin to nest before May, whereas praticola, there 
as elsewhere, nests in March. The mystery of March nests, then, 
begins and ends in the Prairie Horned Lark. 

On finding nests and the reactions of nest-building and egg- 
laying Larks.—The first preliminary to the location of a nest 
is to find the singing male. Having done that one has an idea, 
within a hundred yards, perhaps more, perhaps less, where the 
nest is or where it will be located. But the nest is still far from 
being found. Mouseley (1919) writes that he locates the fa- 
vorite song post of the male, then marks out an area twenty to 
thirty yards in each direction, this he examines carefully or 
watches the male until he flies to the nest. By this means he 
located three or four nests, one of which had young. Rarely, 
in observing the actions of Larks in thirty-one nestings, have 
I seen the male approach an incubating female unless the female 
was first disturbed. Likewise the ‘‘favorite’’ song posts of a 
male may be numerous and some as far as one-hundred to one- 
hundred and fifty yards from the nest. If there are young in 
the nest the male, in feeding, will, at times, give the location 
away more quickly than the female, in other cases the reverse 1s 
true. But, outside of a general indication of a breeding area 
denoted by song, the male has never been of great service to 
me in finding nests with eggs. 

Tt is my belief that, except for mere accident and the rarest 
kind of accident at that, a nest cannot be found between the 
beginning of egg-laying and incubation. As far as I ean ascer- 
tain from the literature, very few such have been found (ex- 
cepting possibly McDonald, 1916) and, considering the unbeliev- 
able inconspicuousness of a nest even in the bare areas where 
it is placed, its chances of being found, unassisted by actions of 
the parent bird, are negligible. Neither female nor male ap- 
proach a nest in this state and though one can know from the 
actions of the birds (extreme nonchalance, an infinity of leisure 


* Since the above was written th it 1 of fil actia 
with a companion, Mr. Paul Walker. “10 ager Frage Gs ris al: 
March nest of Otocoris alpestris 
at San Jose, California a (March 25, 1928). : 


Reproduction 69 


for instance), the exact condition of their nest, to find it is 
another matter. Despite this fact and the knowledge of the 
hopelessness of such a search, I have gone over promising sites 
examining every inch for hour after hour until the sum total 
so spent had accumulated into days of time and have never 
found such a nest, i. e. with eggs just prior to incubation. Ac- 
cidentally, however, students of mine located two March nests 
with eggs that had been abandoned as the result of early April 
snows. 

It is easier, though by no means simple, to find a nest in the 
process of construction. The female at this time is assiduously 
attended by the male, and, in addition, displays a restlessness 
(runs back and forth, is quiet for short intervals only, flies up 
and away but shortly returns), quite different from any other 
period of the nesting. But she approaches the scene of her 
prospective nest with extreme reluctance while an observer is 
near, even within fifty yards, and hours of watching may be 
necessary before the nest site is located. Four recently ex- 
cavated nest cavities were found by this method and one or two 
partially constructed nests. It should be added, however, that, 
though in one case material was added after the cavity was 
found, in no case was any nest completed after its discovery. 
Hither the bird is so timid that she deserts these early starts 
upon the slightest interferences or so many starts are made (see 
below) that in no case have I been fortunate enough to find the 
one chosen for completion. Apparently Mouseley (1916), is the 
only ornithologist on record who has watched the evolution of 
a nest from the period of the excavation until the set was com- 
plete. And Mr. Wm. Chandler (Sutton, 1927) found a female 
building a nest that later had eggs, but neither of these gentle- 
men make clear just how they located the structures at their 
beginnings. 

After the bird has begun to incubate the case is far dif- 
ferent. Then, knowing that the female most frequently will 
leave her nest at from thirty to seventy-five yards, in advance of 
any intruder, in a very characteristic ‘‘casual-abandonment”’ 
flight low over the ground, one has but to march back and forth 
over the breeding territory until she is seen to leave. Frequently 
then it is necessary to reapproach the apparent nest-spot from 
different angles on subsequent visits before the nest is disclosed. 


70 


Trans. Acad. Sci. of St. Louis 


Some birds leave their nests at such a distance that they cannot 
be seen. However the male usually becomes attentive when the 
female is off and by watching him one —— aware of her. 


4 


(10) 


i 


(16) 


ice 
E 


-— 
ay ~ 
~ 

& 


i 


410 


N 


__200 yards scale _, 


Area: 81.95 acres 


19 
(13) (14) 
1 
(19) (20) 
if 


Fig. 9. Location of the nests of the Prairie Horned Lark on the Main 
real-estate Subdivision at Evanston, Ill, 1926. 


Close attention then to the female may, after an uncomfortably 


long period, di 


disclose the nest when she returns to it. If, for any 


reason, such as activities of farm horses, machinery, workmen, 


ete., near a nest, the female is kept for too long a time from 


it, 


Reproduction 71 


she will gradually lose her instinct of concealment by abandon- 
ment, show solicitude by her presence, by running here and 
there and in ground-picking, and finally go onto her nest with 
an observer comparatively close at hand. It should be added 
that, in a few eases, the female Lark may sit close and the nest 
then is found only by an accidental flushing of the incubating 
bird. Again as Harris (in Bendire, 1895) brought out, she sits 
closer toward evening and, as I have noted, when the day is 
very chilly. Sutton (1927) also, after a lengthy recital of the 
actions of a pair of Larks whose nest he was endeavoring to 
find and for which he describes many of the reactions tabulated 
above for nest-building and egg-laying birds (though these sig- 
nificances he did not realize), finally found his nest near dark 
by flushing a close-sitting female. 

The remarkable luck of the writer in finding seven nests in 
one day (April 18, 1926) was because of some unusual circum- 
Stances. First, there were many Larks on the Main Subdivision 
at Evanston; secondly, all began incubation almost simultane- 
ously (because conditions for renesting in April had suddenly 
become propitious, see Figure 6); thirdly, the most desirable 
nesting site was that of the grass strip between the sidewalk 
and the dirt mounds in the center of the street (see Plate XII, 
Fig. 1; Plate XIII, Fig. 2). 

All that was necessary to find the nests here was to tramp 
these strips over and over until the nest of every bird that 
flushed was located. Since the day was cold and I attempted 
to approach against the concealing clump of verdure on the 
north side of the nest, many incubating birds did not flush 
until I was nearly upon them. To find their nests then, was 
simple. 

Nests containing young shortly after hatching may be found 
by watching the female leave, as she does when incubating. 
Later the parent birds will give away the nests while carrying 
food. But, unless the position of the nest is spotted within a 
few feet, many minutes, sometimes hours, will be required even 
then to find it, so protectively colored are the young whether 
in down or juvenile plumage (Plate XX XIII, Figs. 1 and 2). 

Nest Building.—The nest cavity seems to. be dug by the 
female in all cases as no evidence of using a ‘‘natural depres- 
sion’’ was ever noted in spite of many literature references to 


TABLE 3 
Locations and protections of nests of the Prairie Horned Lark at Evanston, Ill., 1926 
Date Environment Protection 
Nest No. | Completed* 
General Immediate Position Character 
1 March 4 Eva Btreetway..i..464.) Dead Agrostis agi ho Ww. dewalk 
2 March 22..... le icon hazard..... Bare ground, dead Setaria..........5..+85 Ww, Dead stems of Setaria 
3 April tte ew dle f OOO ON tac eeecs Dead Agrostis palustris and others......... N. W. Dead weed clump, sp.? 
4 ADT TB visa eae way advo a Dead Agr on , bare ground, Tara- 
zacum officinal N. W, Dead Fy Weil ron repens 
5 Or Le i368 TOCCWEN beaks: Bare ground, ON TEPENB.. ce cceceves N. W. Dead Cir. arvense, dead Agropyron repens 
6 April 12. ie: Streetway.......... Dead Agrostis palustris. .... 06.00 e cee ees N. Dead y sion palustris 
7 April 13...... Streetway.......... ad Agrostis palustris, old boards......... N, Dead Agrostis palustris 
8 April 13.0.4. OWAY ey sans 8 Bare ground, dead Poa pratensis.......... N. Tuft of dead Poa pratensis 
9 ADL IS ovis; Streetway.........- New Achillea on ee bare ground, dead 
Agrostis palustri ‘ Tuft of A. pete 
10 Apt 19.54.5443 Streetway........+. Dead Agrostis pa Il sides | A, palustri. 
11 April 14) 6. i464 Within block........ ager ground, icon foe ede sp? Setaria, None) 
one 
12 April 14...... Within block........ Pah vashtt bien by dead Poa pratensis......... N. Tuft of dead Poa pratensis 
13 April 26...... Streetway.......... Bare ground, new Agropyron News eam (None) 
14 April 27...... Streetway.......... Dead and new Agrostis palustris........... N. Tuft of dead Agrostis palustris 
15 OY Ais sca treetway......e.s. Stems of Oenothera biennis, bare ground, dead 
and new Agrostis palustris. ..........++- N. W. Tuft of dead Agrostis palustris 
16 May 7. 355 Streetway.......... B ground, a little dead Agrostris palus- : 
tris, dead Cirsium N. Dead Agrostis palustris 
17 May Gi 3 2c. Streetway.......... New Agrasis elie, "re pratensis, Agro- . 
pyron re Ww. Sho: ft of Agropyron repens 
18 May 21. 3.4% aaa bec ye elas New and old ree ostis palustris N. New A. palustris 
19 May 22......) Streetway.......... re ground, new Hordewm jubatum....... N. W. Tuft new Hordeum jubatum 
20 May 25....., Old erent Ebi ew bss ee short, new Agrostis palustris. ......... N. A. palustris 
21 wune 9.0 cose. Old hazard......... Bare ground, yo Ambrosia artemisiaefolia N. gosta artemisiaefolia 
22 June Lh. aes Old truck garden Bare ground, Brassica arvensis..........+- W.N. W. | New plants Brassica arvensis 
23 Hane 28. Id truck ck, , Chenopodium album.......... | N. W. | Chonopodium a 
24 June 27,.....]| Old truck garden....| Young plants Xanthium canadense......... | All sides | X rare an canaden. 


*Estimated. 


T 18 fo wg “pooy ‘suviT 


sino 


Reproduction 73 


the contrary. This cavity is most probably dug with the bill, 
though there is no positive evidence on that score. However 
Sutton (1927) after saying (page 136) that a ‘‘natural de- 
pression is sought,’’ adds (page 138) that the ‘‘female was 
working busily . . . the bird dug at the earth with her bill and 
kicked the loose material out with her feet.’’ Usually the exea- 
vation is made partly under a clod or a tuft of grass (Plate V, 
Fig. 2; Plate VI; Plate VII, Fig. 1). The bulk of the material 
placed in this cavity consists of grass stems and leaves and often 
heavier weed material with comparatively coarse roots and much 
dirt. The lining is usually of finer material, plant down, paper, 
feathers, fine rootlets. For a careful and extensive tabulation of 
nests, nest sizes, sites and materials see Tables 3, 4, 7 and 8. The 
photographs of numerous nests among the plates will give also 
the structure and location of nests at various seasons. 

The time required for nest building was not ascertained def- 
initely. Mouseley (1916) gives four days for this phase in a ease 
he carefully watched after removing the eggs of a previous set. 
The eggs were taken April 14, the new nest was begun the next 
day, completed April 18, the first egg was laid April 9. My 
observations showed, in the case of renestings in April after snow 
had destroyed previous nests and in one case where cultivation 
destroyed a nest, that the Lark works at times considerably 
faster than this. Thus on April 6, 1927, at Ithaca, one Lark 
dug three cavities, almost completed the lining of one on that 
date (eight or ten hours), but then abandoned all of them. The 
nest she finally occupied was not discovered until after incuba- 
tion had begun, but counting back from the hatching date, allow- 
ing the optimum incubation period (11 days), she must have 
completed this fourth nest-start between the 6th and the 8th, for 
the first egg was deposited on the latter date. It is probable 
that this nest was also begun on the 6th (for the female was 
repeatedly observed in the vicinity where the nest was finally 
found), and that she completed it in two days time or less. 

Seasonal Variation in nest structure—An often repeated 
Statement regarding Lark nests must be considered before the 
subject is dismissed. Thus Davie (1889), quoting Jones (1892), 
Bendire (1895), quoting Harris, Hess (1910), Sutton (1927) as 
well as other writers, say that later nests are more poorly built 
than early nests. This is attributed to a lessened ‘‘necessity’’ 


TABLE 4 


Location and protections of nests of the Prairie Horned Lark at Ithaca, New York, 1927 


ties No. Date Environment Protection 
Completed* 
General Immediate Position Character 

Bi March 15..... Hillside, fall wheat...| Bare ground, rows of short fall wheat...... Ww. Short fall wheat 
Ai March 20..... Fall wheat... s<ss': | Bare ground, row of short fall wheat....... Ww. Short fall wheat 
Be ROA Bos cis Fall wheat........+.| Bare ground, row of fall wheat w. Fall wheat 
D AON 65.5: Plowed meadow..... Scant tufts overturned timothy (Phleum 

pratense) bare furrows N. W. Tuft of dead, overturned timothy 
Ci Avril 31. 2... Pal v96; i+ ....| Bare ground, rows of fall rye 8. E. Heavy weed roots 
Aa April 92...... | Fall wheat.......... | Bare ground, rows of fall wheat, young 

timothy N. Fall wheat 
Bs June 4.......] Bare garden soil..... | Bare, fine soil, 2 or 3 stems of rye......... N. W. Two small clods 


FL 


T 19 fo ‘wy “poop “SsuD. y 


. 


Sino 


TABLE 5 
The “‘pavings” of the nests of the Prairie Horned Lark at Evanston, IIl., 1926 


Nest N Date* C. leted a Nature of No. of ize of Size of 
0. a omple re) : 
. “Paving” “Paving” Items Smallest Item | Largest Item onaesnaaoicee 
: March 22......... 8. E. Items run |together by rain 
: March 22......... E. Items run |together by rain 
AOL AL is. ; 8. BE. ween Total dimensions 10.2 by 30.6 centimeter 
Apri bake 8. E. Items run |together by rain 
Bor 2.0.5... .; 8. 50 1.8 by 2.9 Total dimensions 6.4 ed 25.0 centimeters 
} April 12,..... cates 8. E. 25 6 by .6 1.2 by 1.8 Total 5 eewonernes 15.2 by 7.6 centimeters 
WOM IS. ccs. ce 8. W. 18 6 by .6 1.2 by 1.8 Total dimensions 3.8 yee 12.5 centimeters 
April oe 8. 30 3 by .3 2.1 by 2.1 Total Ghinenalona 6.4 by 15.2 centimeters 
April Sikiteces 8. E. 18 6 by .6 2.5 by 3.2 Total dimensions 7.6 ie 15.2 centimeters 
10 Ag 18;.;.65 <5. All sides 15 6 by .6 1.2 by 3.2 Scattered about nest 
] April No apparent “paving” 
] Avril 14. .50050555 8. 8 a 3G by 1.2 by 1.8 Total dimensions 6. tx y 12.5 centimeters 
year } ies ce, N ie 7 run |together by rain Total dimensions 7.6 by 10.2 centimeters 
) Ce ge: Se ea 8. E. 30 1.2 by 2.9 Total ae 9.6 by 12.5 centimeters 
j May Sooo ee wa ay “paving” 
‘ Mey Abe ae af E. preme run by rain = from nest 20. 4 centimeters 
eres s oe . Per be ees eke 1S Cee eee ery meager “paving 
} May 22 ee cea 8. E. Items run |together by rain “arcs sal Ma 
) May 25..... Stay 8. Items run |together by rain 
L June 9....... ee 8. E. Items run |together ey POI ae ...| Total dimensions 7.6 by 10.2 centimeters 
2 WUNO 1d oa ss i 8. E. Items run |together by rain 
3 une 22 N. E. Items run |together by rain 
1 VUNG BT cei ccc E. Items run |together by rain 
*Estimated. 


NOTE: All measurements in centimeters. 


uouonpo.day 


GL 


76 Trans. Acad. Sci. of St. Louis 


for good nests, since ‘‘the season is warmer.” Jones (1892) 
takes it as a matter of course and writes that nests in February 
or March ‘‘would very naturally be more elaborate and warmer 
while those in July would be very slight.’’ I hesitate to at- 
tribute any such prescience to the Larks. I thought by weighing 
the nests to prove or disprove this, but the weighings show 
nothing (see tables 7 and 8) for the dirtier material of later 
nests overbalances any lessened bulk of material. It is true, in 
general, and in some cases conspicuously so, that later nests 
have less bulk, less material than earlier, even for the same in- 
dividual (see Table 8.) The explanation for this lies, I firmly 
believe, merely in the fact that there is far less desirable ma- 
terial later in the season than earlier, for vegetation has grown 
up to conceal and to make inaccessible the dead grasses, or rains 
of May and June have rotted them down. To confirm this take 
the case of nests B1, Bz, Bs (Table 8). Bu, in March, was bulky, 
well made, of fine rootlets and weed stems; Bz, in April, was 
a flimsy affair of dirty stems and leaves; but Bs, in June, was 
well made, about as bulky as Bi. The explanation is simple. 
Just prior to the construction of this third nest a field of fall 
rye was turned under. On this overturned ground Bs was 
placed and great quantities of fresh, fine rootlets and dead leaves 
of the rye were near at hand. Sutton (1927, p. 136) also at- 
tributes variations in nest structure to variations in availability 
of material and adds that first nests are better because there is 
more time before the ‘‘onerous duties of brood-rearing have 
been assumed.’ 

One thing more is to be mentioned concerning the nests of 
the Prairie Horned Lark. This seems to have more than 4 
little of prescience in it. By a reference to Tables 3 and 4 it 
will be seen that nearly all nests were, in spite of their open lo- 
cation, placed beside some protecting object, usually a tuft of 
dead grass. There is something more than mere chance ope!- 
ating here, that of more than thirty nests nearly all should have 
this protection on the west or northwest. 

“Pavings.”—About a portion of the rim of the nests of 
O. a. praticola, usually on the side away from the protecting 
elod or grass clump, there was nearly always a definable layer 
of material (clods or pebbles), which the Lark had laid down 
during nest building. Peabody (1906) has, very appropriately, 


TABLE 6 


The “pavings” of the nests of the Prairie Horned Lark at Ithaca, New York, 1927 


} Nature of Position No. of Size of Size of 
Nest No. | Date* Completed | “Pa ving we o Items Smallest Item | Largest Item Miscellaneous 
av ng” 

Bi waren 16..5., 5... Pebbles. . N.E. 17 .6 by 1.3 1.9 by 2.5 Weight of largest pebble 2.4 grams 
rete ae eeu oa re ; 8. E. 4 -5 by 1.2 1.6 by 2.5 Very meager “paving 

ef Agni G........... 8, 

bbl 8. Very meager “paving” 
S Fatt. >... Clods, 
pebbles 8. 17 1.2 by 1.8 1.8 by 3.2 Total dimensions 8.9 by 8.9 centimeters 

Ci April 21 No spenrent “paving 
As April 22 33 ec “paving” 
Bs June 4 He oni ‘paving”’ 

*Estimated. 


NOTE: All measurements in centimeters. 


uousnpou.day 


LL 


78 Trans. Acad. Sci. of St. Louis 


ealled this a ‘‘paving.’’ The first instance of this sort of thing 
seems to have been cited by Silloway in ‘‘Birds of Fergus 
County, Montana.’’ Peabody (1906), refers to this account but 
I have not had access to it. Silloway described these pavements 
as ‘‘dirt or clods or fragments of cow-chips.’? The pavements 
noted by Peabody were of ‘‘gumbo,’’ of which ‘‘2 or 3 bits’’ 
were used at one nest and 40 at another. A third had ‘‘cow- 
chips.’’ Silloway and Peabody’s accounts (in Montana and 
Wyoming) referred to O. a. leucolaema. Mouseley (1916) was 
the first to record a ‘‘pavement” for praticola. He describes 
it as of cow-chips and (another nest) of flat pebbles or stones. 
In most of the photographs of nests accompanying this article 
a ‘‘paving’’ is visible and in others it is present but the sep- 
arate items have been obliterated by rain. In my opinion prac- 
tically all nests of praticola have this pavement though it may 
vary considerably in shape, size and number of items. See Tables 
5 and 6 for an account of the details of this interesting struc- 
ture at all of the nests at Evanston and Ithaca. 

Mouseley (1916) suggests that the Lark uses for ‘‘paving”’ 
that which is best suited, thus: ‘‘As regards the paving it [the 
bird] seems to have displayed that marvelous instinet which 
birds seem at times to be endowed with, for instead of using 
cow-chips as a paving which, in such a wet, spongy place would 
have been of little good, it resorted to the use of very thin and 
flat stones.’’ In my opinion the bird uses what is most acces- 
sible—at Evanston clods, at Ithaca pebbles—and shows no pre- 
Science whatsoever in the matter. If it does why should it have 
used clods almost exclusively at Evanston which the first rain 
would beat down and wash together when, by going a trifle fur- 
ther, it could have had an admirable assortment of pebbles left by 
the sidewalk contractors? Probably clods, formed by the drying 
of the surface that follows rains on the barren areas that the Lark 
inhabits, constitute the chief materials for ‘‘pavements’’ of 
praticola. That they have not been recorded more frequently 1s 
easily explained: a single rain obliterates a clod pavement and, 
moreover unless attention be called to it, even a freshly lai 
pavement may be overlooked. Thus a photograph of @ nest 
taken by Allen (1925) at Ithaca, shows a good pavement but he 
had not noticed it until the writer called his attention thereunto. 
And again a meager pavement appears in a photograph by Wm. 


TABLE 7 
Material, sizes and weights of the nests of the Prairie Horned Lark at Evanston, Ill., 1926 


N ee Materials Measurements (centimeters) Weight 
No. Completed* T a 
‘op ext. Top int. Depth Depth grams 
Amount Body of nest Lining dim. dim. inside overall 
1 March 22.,.,...}| Much......]| Stems and leaves of blue] Fine grass, heads of 
e (Poa pratensis)..| aster 21,3 
3 April 1 (No record) 8.4 6.6 5.5 634... a eR 
4 April 12 (No record) o.1 eck 4.6 Core Serine PSS aati Gant 
5 April 12 (No record) 8.1 6.6 4.8 ant wales AR aS ‘ 
7 April 13 (No record) 8.6 6.4 4.5 Gir ae ks ‘ 
8 pril Fine grass only (Poa Aster heads, grass 
os tae a vo ahh, CoC ne 8.9 Be he as ue yi Seidl exe flat oe 1s 
9 April 13 rass stems and leaves.| Feather, paper bits, fine 
grass stems and leaves. 9.6 6.7 3.8 Glo hae ar 
10 A Tacs... . Much......| Coarser stems, leaves,| Aster s, plan 
BONG GE. ess ROPE ea as 9.6 7.6 4.1 5.8 12.1 
il April 14 Grass leaves, stems....| Fine roots, aster heads, 
grass leaves.......... 8.8 6.4 5.9 450° Shi eee . 
12 April 14 GNo record)... 66. .eh. 9.2 6.7 4.1 pout Wiican Sere Ayers Gt i 
13 April 26..... Medium.. * few te pre om or Srempi grass 
leaves, weed s PE OBVOR Si cece ES 7.6 6.4 4.6 6.4 9.4 
14 April 27 (No moe mei 10.1 4.5 5.0 6402 hee eae 
15 ay 3 RO FOCOTG) ke hey os chs ee ek 8.6 a7 5.0 6.9. Cie Z 
17 May O. vice. ...| Medium.... Pine, sy seg OME ies: Grass leaves, — — 8.0 6.6 5.1 T8238 eee 
18 MAY 2) ics... Much...... Grass — and leaves,| Fine plant fiber 
few fine roots......... grass leav eres a 8.9 tek 4.8 6.7 14.7 
19 May 22 iether cae scrap Paper S. . 
Of GION ee Se ai fibre, pring eae 9.1 6.7 4.8 6.) fae ‘ 
21 dune GU. 2.53.5... Small......| Stems of Setaria, other 
coarse material, much 
dirt Same as body......... 8.6 6.9 4.8 5.9 14.9 
22 June 17........ Small......| Some roots, stems — 
leaves of grass, dirt. ..| Paper, heads of aster .. 8.9 7.4 3.0 5.8 10.1 
23 June 22 ae Much... 2. Roots, coarse stems and 
weed leaves, much dirt.| Same as body......... 9.2 7.8 4.8 6.3 24.4 
24 June 37... ....:} Moch...:; arse Wi stems and 
leaves, afew roots, art. Same as body......... 8.4 6.7 4.6 5.8 15.4 
Average: 8.82 6.87 4.65 6.27 15.28 


*Estimated. 


wouonpoidagy 


80 Trans. Acad. Sci. of St. Louis 


P. Chandler (Sutton, 1927, p. 189) and a rather extensive one 
in a beautiful photograph by Frank Pagan (Forbush 1927, pp. 
356-357). Likewise, I do not hesitate to say that if I had not had 
Peabody’s article in mind at the time the nests were found I 
might never have noted, in the field, these structures which seem 
so obvious in the photograph. 

The purpose of pavements seems clear. Though it may serve 
as a decoration, a concealing structure or in some such capacity 
as is attributed to snake’s exuviae or rags found at other birds’ 
nests, I believe its origin can be traced to two things: (1) the 
method of building the nest and (2) the Lark’s persistent de- 
mand for bare surfaces upon which to walk. Under the first 
point it should be remembered that the excavation is built back 
under an object on one side and has a long slope on the other. 
Nest material is not laid out to level up this slope but the pave- 
ment is (see Figure 10, also Plate VI, Fig. 2 and Plate VII, 
Fig. 1). Though Mouseley has shown, in one ease, that the 
pavement was entirely laid before any nesting material and Fig- 
ure 10 would not correspond exactly with his description, yet 
the purpose of the pavement could be the same in either case. 
And, too, a study of the construction of many nests seemed to 
show, that in some cases at least, pavement is laid after the nest 
is completed for much of the paving was above and over the 
outer edges of the nest material. The demand for a bare ap- 
proach to the nest and the consequent laying of a pavement to 
cover up intervening grass or nest edges seems to constitute 
another reason for this interesting structure. To substantiate 
this see Plate X, Fig. 2; Plate XI, Fig. 2; Plate XII, Fig. 2; 
Plate XV, Fig. 2. And some nests which had bare ground on 
all sides had no appreciable ‘‘pavement’’ (Plate XIV, Figure 2 
and Plate XV, Fig. 1). But, in order that the theory may not 
be too perfect, some nests which were surrounded by grass and 
should, under this hypothesis, have had the most extensive pave- 
ment had perhaps not more than a single, insignificant item (see 
Plate XVII, Fig. 1). In concluding it should be remarked that 
the Larks, if undisturbed, invariably approach the nest over the 
pavement (see Plate XXVIII, Figure 2). 

Eggs and egg-laying.—The ege of the Prairie Horned Lark 
has been described over and over in the evolution of ornithology 
from the “‘science’’ of odlogy. But, as far as I know, no one 


TABLE 8 


Material, sizes and weights of the nests of the Prairie Horned Lark at Ithaca, New York, 1927 


Materials Measurements (centimeters) 
Nest Date , roa 
No. Completed 6 
Top ext. Top int. Depth grams 
Body of nest Lining don. dim. overall v 
3 
Bi March 15....... Weed stems, fine roots, i 
dirt Fine roots 7.6 by 8.9 | 5.1 by 5.8 5.8 10.7 Qu 
Ai March 20 Weed stems, dirt, fine ~ 
FOOLS. oes on Aster heads 9.6 by 10.2] 5.8 by 7.1 5.3 10.1 < 
Ba April $, 60.4.3. and leaves of Ss: 
Setaria, a fine roots.) Same as body....... 7.6 by 10.5] 5.1 by 5.5 4.8 7.9 3 
Aa Apr 2) os Coarse stems of Arapenron: <. 
muc 
dirt Several feathers..... 8.3 by 10.2] 6.4 by 7.1 5.1 12.0 
Bs Jane $s Fine roots and leaves 
of rye Same as body....... 7.6 by 9.6 | 5.8 by 6. 9 4.5 8.7 
Average: 8.14 by 9.88] 5.64 by 6.48] 5.10 9.88 
*Estimated. 


[§ 


82 Trans. Acad. Sci. of St. Louis 


has compared the color with Ridgway’s (1912) standards. On 
this basis the egg may be described as elliptical, rather unusually 
pointed for a Passerine bird, with a ground color of grey or, 
occasionally, with a greenish tinge. The spotting is fine, uni- 
form, almost completely concealing the background, and is cin- 
namon-brown in color. The eggs are quite uniform but many 
have a denser ring of pigment about the larger end (see Plate 
XVI, Fig. 2). Saunders (1899), describes in Otocoris alpestris 
flava of Europe occasional ‘‘hair-lines” about the larger end. 
One case of this was observed in praticola (see Plate XVI, Fig. 
1). Another interesting color variation was that of a single 
egg in two nests of the ‘‘B’’ female (nests Bz and Bs). Here 
a deficit of pigment caused the egg to show more background 
than normal (see Plates IX, Fig. 2, and XVIII, Fig. 2). It 
was probably the fourth and last egg laid for it was the last 
to hatch. Nest Bi had but three eggs so this type of coloration 
did not appear in it. Incidentally this egg, as well as the charac- 
teristic actions of the bird, made positive the identity of the 
owner of the nests and confirmed the evidence of the territory. 

There is but little of significance in an egg measurement, still 
twenty-two eggs of nine different nests were measured. The 
average length of the twenty-two was 2.25 em., the average width 
1.55 em. The smallest was 2.13 by 1.46 em., the largest 2.45 by 
1.58 cm., the longest 2.45 em., the shortest 2.13 em., the broadest 
1.66 cm., the narrowest 1.46 em. Mouseley (1917), in his study 
of second sets, found a considerable descrepancy in size (.82 by 
-58 inch average first set as opposed to .78 by .58 inch average, 
second set). My results are the reverse of this. A single egg 
of Nest A1, laid about March 15, measured 1.58 by 2.13 cm., 
three eggs of nest Az, laid between April 21 and 23, were all 
of the same measurement, viz., 1.58 by 2.22 em. 

The number of eggs per set varies from two to five ordinarily, 
though Levy (1920) records a most exceptional case of eight 
eggs in a nest. March nests have the smaller sets, usually two 
or three. Five nests of two eggs, eleven of three, eleven nests 
of four, five nests of five, made up the sets of the nests at Evans- 
ton and Ithaca. Some of these, of course, had hatched before 
the nests were found. There is probably a close relationship be- 
tween temperature and small sets in March (sets of five occurred 
only in late April, May and June). Nine eggs of five sets at 


Reproduction 83 


; ee 
3 Se 
<a wae “protecti ‘elod 
i, wnt — — 
j WN gras 
a \ ) \ 
r ; fie en oe thrown up AN \ wa 


me from the excavation 
~---— the excavation 


The Nest-excavation in Cross-section 


“7 firat items /of 
’ “paving 


- 
a 
2 


Completed Nest and "Paving” 


Fig. 10. The construction of the nest of the Prairie Horned Lark, 
with an explanation of “pavings”. 


84 Trans. Acad. Sci. of St. Louis 


Evanston averaged 2.19 em. by 1.50 em. The thirteen eggs of 
four sets at Ithaca averaged 2.28 em. by 1.59 em. Whether there 
is any significance in this discrepancy I cannot say. Though 
Ithaca eggs were larger, on the other hand, Evanston nests 
were larger. Probably both discrepancies would disappear. in a 
large series. 

The actions of the adult birds during egg laying have already 
been discussed under nest-finding. More need not be said here 
except that the actions of the female at this period are those of 
a bird with an infinity of leisure, patience and unconcern. She 
does nothing but remain quietly in one place, forever preening 
herself. The male at this time, attends her as assiduously as a 
groom. Now frequently incubation begins before the set is 
complete but the actions of the female then constitute another 
matter. 

Incubation period.—Forbush (1927) gives the following pe- 
riods of incubation: 12 days (H. O. Green) ; 11 days (L. Mel. 
Terrill) ; 14 days (A. W. Butler). Jones (1892) puts the aver- 
age at 13 days and says, “I doubt if any eggs are hatched in less 
than 12 days.’’ As already has been noted no nest was fol- 
lowed from the time of the first egg to hatching, but in three 
instances the last egg was laid after the nest was found. This 
last egg, or the last young which was most probably of this egg; 
hatched on the 12th day after laying, in the three cases. From 
the time of laying to the time of hatching about eleven days 
would have intervened. The incubation period determined by 
MacDonald (1916), for O. a. leucolaema, was in exactly the 
above fashion; a fourth egg was laid after a nest with a set of 
three was discovered: All hatched within twenty-four hours of 
each other, eleven days from the laying of the last egg. Her 
conclusions that incubation extends from eleven to fourteen days 
is unwarranted, however, for it is at once obvious (since all 
hatched together), that incubation did not begin until the last 
egg was laid. At Evanston, however, the last to hatch was often 
a full day behind all the others in many of the early sets, that is, 
three would hatch within an hour or two of each other, the 
fourth almost exactly twenty-four hours later. No other con- 
clusion is logical but that incubation began the day before the 
last egg was laid (the nest was found because the bird had be- 
gun to incubate) and that eleven days is the period for all. 


TABLE 9 


History of the successive nests of territories A, B and C at Ithaca, New York, 1927 


Nest Date No. of Position in Distance Fate 
No. Completed* eggs territory from former nest 
Ai March 20 : 2 East center........ Destroyed by snow. 
Aa April 22) 606.35 3 West center........ 85 yards Three young successful. 
Bi March 15....... 3 South margin...... Destroyed by low temperature and snow. 
Ba April 8...... ee 4 West center........ DIG yards... 3.04 ess One young only successful. 
Bs 0000 455.5 554.65 4 West margin 40 yards Destroyed by Cowbird experimentation. 
Ci Apr 93.43... 5 East margin....... Three young successful. 
C2 May S65 a. ? Nest not located. , Not known......... Three young, at least, successful. 


wouonpoidaay 


S8 


86 Trans. Acad. Sci. of St. Louis 


Bergtold’s (1917) record of 11 to 14 days is given on the au- 
thority of MacDonald. In one ease in the writer‘s experience 
incubation extended for a known period of fourteen days but for 
some unknown reason the nest was deserted, apparently, for two 
days after incubation had begun (the eggs were cold), and this 
probably accounts for the unusual period. Considering eleven 


TABLE 10 
Reactions of the Prairie Horned Larks to man when eggs were in the nest, 
at Evanston, Ill., 1926. 
Nest No. No. of Visits | No. of Times | No. of Casual |No. of Distress| No. of Other 
Parent Noted |Abandonments| Simulations Reactions 
3 9 5 1 2 2 
5 4 0 1 3 
6 5 5 4 0 1 
7 9 6 2 2 2 
8 4 3 1 1 1 
9 14 8 7 0 i 
10 11 3 4 0 1 
11 10 8 1 5 2 
12 8 6 3 1 2 
13 10 8 3 1 : 
14 11 8 5 1 3 
15 11 il 5 0 - 
19 11 & 6 1 i 
20 5 4 3 0 fp. 
21* 12 p 
10 8 0 B2 
sa : ; ‘ 0 % 
pees 
Total 055-3. 142 105 59 15 = 
SpE apr emer ee ad ee 


days the optimum I have used it as the basis for estimation of 
all the tables and figures where dates of egg-laying and nest- 
building are given. 

_Though Bendire (1895) and Criddle (1917) say the male as- 
sists in incubation (Criddle does not specify incubation but 
Says “relieving the female upon the nest’’), I have no 
evidence that the male ever incubates or broods. I have de- 
termined the sex upon hundreds of visits to many different 


Reproduction 


87 


TABLE 11 
Reactions of the — Horned Larks to man when young were in the 
nest, at Evanston, Ill., 192 


Nest No. No. of Visits r Pees Noted Pehahe toners ed helo gi Par og 
3 11 7 4 1 2 
4 7 3 1 0 2 
5 7 5 0 2 3 
7 11 8 1 0 7 
9 10 6 4 0 2 
10 il 1 1 0 0 
1 10 3 3 0 0 
12 9 2 0 0 q 
13 Bl 5 2 0 3 
14 1 9 2 1 td 
15 10 7 0 0 7 
19 3 2 1 1 : 
20 19 ul 6 1 ‘ 
21 9 5 0 1 : 
22 9 9 3 0 ? 
Teel. 2s. 148 83 28 7 ais 
TABLE 12 
Reactions of the Prairie Horned Larks to man when eggs were in the nest, 
at Ithaca, N. Y., 1927. 
Nest No. No. of Visits Eee hare Poste Beamer : gf sed ycnags 9p hc towed 
Ai 11 a 2 : : 
As 11 7 6 : : 
Bi 2 2 0 ; 
B2 6 . 5 0 4 ; 
Bs; 4 : 3 0 . : 
C; 8 ad’ t “ : 
D 6 ” & “ : 
Le ee 
Teles. 48 28 16 : : 


88 Trans. Acad. Sci. of St. Louts 


nests and always it has been the female. A full day spent at 
one nest (Table 15), failed to show the male in any inclination 
to incubate. Similarly a full day at a nest with young (Table 
17) failed to show that the male broods. 


Reactions of female and male Larks during incubation pe- 
riod.—The reactions of the incubating female express some of 
the most highly-developed nest-protective instincts among birds. 
She has two such instincts with a series between these two. The 
first, and most highly developed, is a reaction I have called 


Reactions of the Prairie Horned Larks to man when young were in the 
nest, at ft N. Y., 1927, 


No. of Times } No. of Casual Ino. of Distress i of Other 
Nest No. No. of Visits [Parents Noted |Abandonments| Simulations actions 

Aa 9 3 1 0 2 
Bi 4 4 0 1 3 
B: 30 16 4 9 3 
Ba 8 6 0 1 5 
Ci 30 11 4 0 7 

he sic 8 ies 
Total oc. 81 40 9 11 20 

Ma ae aig Neve cntece ehm 


the ‘‘casual-abandonment’’. Typically expressed it consists of 
an abandonment of the eggs while an intruder is from one-hun- 
dred to twenty-five yards distant. The female leaves without 4 
sound (usually flying directly from the nest in spite of frequent 
remarks in the literature to the contrary), flies low against the 
ground like a grey wraith and is soon lost to sight. Her flight 
under such circumstances is unique and distinct, most frequently 
without marked undulation, with steady wing beat with a pause 
of time of about one beat between each beat. So highly devel- 
oped is this method of nest protection that the female leaves the 
nest at a greater distance than a timid Lark would fiush under 
other circumstances. Other writers describe this reaction though 
make no attempt to explain it. Thus Merrill (1888) in writing 
of O. a. strigata says: ‘‘The male, who is constantly on the watch, 
seems to call the female off the nest when an intruder is still at 
a distance; several times I saw one approaching her mate, shak- 


Reproduction 89 


ing her feathers and having evidently just left the eggs, but my 
efforts to flush one off the nest were fruitless. . .”? I do not 
believe the male influences the female in any way, ‘bn had gone 
from her nest at so great a distance that Merrill had not seen 
her leave. Brewster (1894) writes that the female sneaked off 
when at some distance, unconcerned, flew with a steady, rapid 
motion of the wings. Bendire (1895) quotes Harris: ‘‘Early 
in the day the female will usually leave before you are within 
50 yards of it, creeping away for some distance, crouched close to 
the ground before taking wing. . . Toward evening they are 
not so cautious, and very often the nest can be approached within 
a few feet . . . the female will fly only a few yards, alight, and 
begin pecking the ground. . .’? Brooks (1899) writes that the 
female ‘‘flies straight away when one comes within 50 feet’’ of 
the nest. Jones (1892), Hegner (1899) and Forbush (1927) 
describe a similar reaction as does Sutton (1927, p. 188) though 
the latter adds a bit of nonsense with the statement that, ‘‘Per- 
haps the birds realize that human beings are acquainted with 
the crippled wing ruse of such species as the Killdeer and have 
decided to use other tactics’’. Jones (1892) also presumed that 
Larks never went ‘fluttering and crying’’ from the nest. As a 
matter of fact Lark and Killdeer respond very similarly (for 
this see further and also the author’s paper ‘‘Nesting of the 
Killdeer’’ cited below). 

The other reaction is a marked distress simulation in which 
the female flushes only after an intruder is well upon the nest. 
She goes then calling and fluttering over the ground at a rapid 
run, horns up, wings flapping. Audubon (1832) describes this 
for both the male and female of O. a. alpestris and Forbush 
(1927) writes that ‘‘sometimes when the eggs are near hatching, 
and she is suddenly surprised while incubating, she may act 
like a crippled bird. . .’’ My observations have shown no clear 
relationship between this reaction and state of either incubation 
or brooding. 

As Harris (Bendire 1895), has said, the nest may be more 
closely approached near night. In other words the typical 
casual-abandonment is best expressed during the lighter portions 
of the day and especially during the warmer days. Distress 
simulation, on the other hand, is more likely to be demonstrated 
near dark, on cold days, or if the incubating bird is approached 


90 Trans. Acad. Sci. of St. Louis 


from the north so that the nest protection conceals the intruder 
until the nest is nearly under foot. But there are many varia- 
tions. Some birds gave distress simulations under many cir- 
cumstances, others gave nothing but casual abandonments. A 
complete graduation between these two reactions, of course, 
existed: the bird would allow close approach at times then leave 
without distress simulation, or fly but stay near and call. The 
unconcerned ‘‘ground picking” was always a sign of an incubat- 


TABLE 14 
protective reactions of an incubating female Prairie Horned Lark 
eae No. Bi, June 20, 1926, Evanston, IIl.). 


Time of Time of Interval Between 
Flushing cig Between Return eturn Reaction 
Female lushings and Flushing 
4:20 a.m 4:30 a.m Casual abandonment 
6:25 2 hours 5 minutes |............ 1 hour 55 minutes | Casual abandonment 
6:35 10 minutes 6:38 Distress simulation 
7:44 1 hour 9 minutes 7:49 1 hour 6 minutes | Casual abandonment 
12:40 p.m. | 4 hours 56 minutes | 12:45 p.m. | 4 hours 51 minutes | Casual abandonment 
3:09 2 hours 29 minutes | 3:14 2 hours 24 minutes | Casual abandonment 
3:20 11 minutes 3:26 6 minutes Casual abandonment 
3:36 16 minutes 3:41 10 minutes Casual abandonment 
3:42 6 minutes 3:45 1 minute Distress simulation 
3:47 5 minutes 3:53 2 minutes Reluctance plus cas- 
. : abando: x narigg 
r 10 minutes 4:01 4 minutes Reluctance plus 
ina : ual aban Fo nical gs 
; 9 minutes 4:11 5 minutes Reluctance plus cas- 
ai : ual abandonment 
: 5 minutes 4:14 0 minute Reluctance rs 
4:14 : soe plus exe 
: 3 minutes 4:17 0 minute Reluctance plus exag- 
= 
4:17 3 minutes 4:20 i tance f 
: 0 minute Reluctance plus exag- 
Sar 
. r i ation. 
4:22 5 minutes 2 minutes Reluctance plus cas- 
is ual abandonment. 
oa 8 minutes 4:35 minutes Casual abandonment 
: 16 minutes 4:53 u minutes Casual abandonment 
5:01 iS hihates © Le, 8 minutes Casual abandonment 
6:30 1 hour 29 minutes |...... Casual abandonment 
cigar 


een ee 
Summary: — of flushings: 20 


eaction when fi time consumed i 4:70 minutes. . 
Reaction flushed imme ae ipeinabe af — to nest: vet 


pian cme when flushed sta ro minute from time of return: distress simulation. 
Reaction w 
leave pies fushed two to five minutes from time of return: reluctance to 


Reaction w when Bushed ive minutes or tore from time of return: normal casual 


Reproduction 91 


ing female. The male, beyond occasional call notes, showed 
little or no solicitude while eggs were in the nest. 

To see if these two reactions, ‘‘casual abandonment’’ and 
“‘distress simulation’’, could be reduced to a formula I spent the 
greater portion of one day flushing an incubating female from 
her nest. The results are given in Table 14. Let me add that, 
in spite of this evil treatment, the eggs hatched in normal time, 
the young prospered until found by a weasel or other enemy. 
Moreover, I have tabulated the recorded reactions for every visit 
to incubating females both at Evanston and at Ithaca. These 
results are given in Tables 10 and 12. The ‘‘other reactions’’ 
here include intermediate types chiefly. Thus it will be seen 
that, though the first effort of a female Lark to protect her nest 
is to attempt to deceive the searcher by an unconcerned flight 
(the ‘‘casual abandonment’’), this highly developed instinct is 
inhibited by various conditions (such as flushing at too close 
intervals), and then the more primitive instinct, that of distress 
simulation, gradually takes its place. In many respects these 
reactions resemble those of the Killdeer (see Pickwell, ‘‘ Nesting 
of the Killdeer’’, Auk 42, 1925, pp. 490-491). 

It has been my intention since beginning work with the Prairie 
Horned Lark to see if the above reactions would be given for 
animals other than man and if they were the same (or different), 
to speculate upon the reasons. No opportunity has as yet pre- 
sented itself for this type of experimentation but two accounts 
in the literature give a clew. Brooks (1908) writes that adult 
Larks at French Creek, West Virginia, alighted on the backs of 
chickens to drive them away from the nest. Criddle (1920), 
also remarks that the female Lark would fly at a hen with such 
vigor as to cause her to become seriously alarmed and to make 
her leave in a hurry. Criddle also makes the important obser- 
vation that before dogs and man the female slipped quietly from 
her nest. This last was, apparently, a typical abandonment con- 
cealment. It appears, then, that the Lark does not reserve a 
Special reaction for man alone but can, however, distinguish 
between mammals and large birds and has distinct reactions for 
each 

The Young 

Hatching —Of hatching there is but little to say. In spite 

of daily visits only once did I arrive during hatching, once only 


92 Trans. Acad. Sci. of St. Louis 


TABLE 15 


A day’s activity of the male Prairie Horned Lark during the incubating 
period (nest No. 21, June 20, 1926, Evanston, Ill.) 


Time of 
Day 
4:20 a.m. Nest reached. se gor -_ in vicinity. 
4:53 ithin 50 feet of n 
4:54 Sotermitrens rheatine peas 
4:59 Intermittent ss song, = — from nest. 
§:25 Greeted fema she le 
5:30 Recitative ground song, 30 fect fro 
5:33 Intermittent aha song — Fee Soy song post, 90 feet from nest. 
5:55 Intermittent ground song and calls, 50 feet from nest. 
6:00 Sitting quietly on mound, 30 ghee from 
6:05 Came within 2 — of t. 
6:14 Intermittent ground song, 30 feet from nest. 
6:15 w from vieeni y. 
6:44 Intermittent ground song, 150 feet theast of nest. 
6:47 Sm ill s rye ng as previously. 
7:03 Singing as previously. delim 
7:12 Tnternittent eee | song, 50 feet due east of nest, h 8 
vegas Intermittent — Sa 2 = feet southeast of nest. — 
7:24 Soft intermittent ground song, 25 feet due east of nest. 
7:25 emained wi 50 feet of at S wrhile formats was away. 
7:33 Intermittent ground song, 150 po oe yer of ai 
8:00 Intermittent ground song, 240 feet south of nes 
8:06 Intermittent ground ren i 60 feet ps anon of soit 
8:09 Soft Parana to — song, 30 feet east of nest. 
8:11 Within 6 feet of n 
8:21 Singing near. 
: a4 Intermittent ground song, 30 feet east of nest. 
8:31 Flew from vicini 
a to During fore ‘to photograph female, male remained near, singing. 
10:03 Flight so 
10:15 Intermittent ground song, 25 feet east of nest. 
10:16 nt ground song south of nest. 
10:40 Intermittent sete song, one ~ a of nest. 
11:39 Intermi tte nt gr song ni 
12:43p.m Flight son, 
1 : an to Intermittent ground song, 150 feet southeast. 
2:00 With female, calling, 30 feet east of nest. 
2:47 und recitative, 150 feet southeast nest. 
3:24 Intermittent ground song, 90 feet south of 
3:30 song, 150 feet southeasl nest. 
3:46 Intermittent ground song, 50 feet 
3:51 Intermittent ground song, 225 feet south of nest. 
4:40 ee ground song, 90 feet south of nest. 
4:53 Intermittent ground song, 300 feet south. 
: = to (Int cho out for observations of other Lark nests.) 
6:39 Flight so: 
7:33 et, 1501 feet ee of nest. 
7:37 vening recita: 
7:40 Sullsinateg sree recitative. 
7:50 Quiet, FS ei ier of nest. sci aaciaeenemmmeensee 
umm. 
Song 
Songrecordsat 25feetfromnest: 3 
Songrecordsat 30feetfromnest: 6 
Songrecordsat 50feetfromnest: 5 
Songrecordsat 60feetfromnest: 1 
rdsat 90feetfromnest: 3 
Songrecordsat150feetfromnest: 8 
Sener —— St 300 feet from next : ; 
ty) eet from nest: 
verage distan 116 feet, or 38.66 yards. 
as f£ ground 28 
oO! ——— 
Periods of aiane cee 5 
Flight songs 3 
Total song periods 36 


Reproduction 93 


while empty shells were yet in the nest and but once or twice 
before the newly hatched were completely dry. The egg breaks 
about the larger end, the young emerges, the parent promptly 
removes the empty shell, the down soon drys and within an hour 
or two, perhaps much less, the nestling supports himself upon 
his belly and wing tips, cranes his neck toward the zenith and 
opens wide a yellow-patched maw. 

Feedings.—The most important thing in the life of a nest- 
ling is food and this is supplied, as a rule, by both parents. In 


TABLE 16 


Observations of the incubating Prairie Horned Lark Female (nest No. 21, 
June 20, 1926, Evanston, III.) 


Time of 


Day 
4:20 a.m. ushed with casual abandonment at 30 feet. 
4:30 Heturned to ims facing southwest. 
4:45 Faced northeas 
5:12 Faced = rab neransr 
5:25 Left n 
5:26 Heteried to — Flew within 4 feet, walked in. 
5:41 Faced northeas 
5:45 Flew from sare alight ted 60 feet away. 
5:53 Returned - som vicinity, bc out a cut worm near nest. 
5:55 Returned t t, faced so est. 
6:09 Parsed cues: { = northe 
6:10 aced southwi 
6:20 Faced northeas 
6:38 Faced sou t 
6:47 Faced we 
6:54 Left n 
— Returned to nest, walked in from 30 feet. 
7:31 ion mee to = wale | in from 30 feet, picked ground. 
7:34 Poet ——— 
7:42 poregalic rtheas 
8:03 Left n 
8:10 Recast to oe walked in from 30 feet. 
8:11 aan northeas 
8:38 aced southw or 
8:42 hes nest, flew 100 yards away. 


(Remainder of day spent in photography and experimentation.) 


one or two cases I failed to see the male with food at any time 
but usually he did about as well as the female. In the case of 
the feedings recorded in Table 17 the male visited the nest less 
often than the female but he usually eame with a much greater 
burden, fed more nestlings, so that, all in all, the case was about 
even between them. For an extensive record of feedings see 
Table 17. This account is for April. Shorter observations in 
June and July gave similar records. It has not been possible, 
as yet, to determine whether or not the rate of feeding varies 
with the age of the young, or just when the male begins to 


Trans. Acad. Sci. of St. Louis 


TABLE 17 


Table of feedings, and other activities of the Prairie Horned Lark (nest 
No. 7, for April 30, 1926, at Evanston, IIl.). 


Interval 
No. of Between % : , 
Time of Retin Reaction to iar Sex Feeding Brooding Periods 
Feeding Excreta 
iets 
5:14 a.m. a Removed Female 
§:21.5 1 Removed.......| 5 emale 
5:47 1 25.5 POMA Bours Brooded 
6:03 2 Removed.......| 1 Female 
6:12 ) POMQNIG C5. Sos ts Brooded to 6:37 
6:44 3 Female......... Brooded 
We es Bp aes Removed....... 25 Female 
y Sal! SARE WAR te 2 eaten, ci. ih $ MPRIGS ous a es Brooded 
7:37 2 Female 
42 } Female 
7:45 3 POMmsle. 6.305 ck Brooded 
8:04 Removed....... 19 emal 
8:06 2 Female. o.oo. Brooded 
8:17 Removed....... i Female 
8:25 Female......... Brooded 
8:38 4 1 Female 
8:45.5 iS Female 
8:51 5 Peinkie. 625 6s: Brooded 
8:56 Removed....... Female 
9:00 Female 
9:02.5 b 5 ‘emale 
9:09 a ob Wee eri s beet Se a ee 
9:12 Male coe: 
9:19 4 MM ers 
9:26 Leatercciessc: 7 Female 
9:34 Lb @aten.o oy: 3 Female 
9:34.5 i 5 ale 
ir 5.5 Female ees Brooded 
! emaie 
O53 Oe ee ee 
9:52 , f — PVeGas l 
oved....,. 
10:01 2 ses : 
10:03 > 
:10 4 
i 
g 
0.5 
7.5 
10 
9.5 
6.5 
9.5 
i 4 - 
1:59 
He | 2 
12:18 Ee r 
12:20 AEA ce eee 
ee : 
* I 
fe bo papain ae 
: ooo sb eaten : r 
46 sid 4] 2 eatem......... 
12:50 t enten.. 34... z 


Reproduction 95 


TABLE 17—Continued 


Interval 
: No. of : Between 
Time of Nestlings Reaction to Feedings Sex Feeding Brooding Periods 
Feeding Fed Excreta in 
Minutes 
12:57 1 3 Female 
12:59 ) ale 
1:02 2 3 Female 
1:17 2 1 ale 
1:20 1 } Female 
PaO: ede wee es pres Beaten ecco s oe 2 Female. 30245 Brooded 
2:09 1 2 le. 
2:14 1 Removed....... Female 

13 2 Removed....... Female 
2:30 1 Removed....... 1 Male 
2:37.5 n? 5 Female 

44 1 Removed....... 5 Female 
2:51 Female 
2:59 1 3 Male 
BG oe era watck Ghtelh ow, wei. 3 Female 
3:09 1 Female 
3:12 ala 
3:14 1 Removed....... Femal 
3:28 14 Female 
3:31 é Male 
3:33 : Male 
Sapte War ar eat MON Co mad eT Cis ab ( Female 
We Sek oe ea nae 2 eaten, 5c oe Female 
3:38 1 Lesten.s 345003 Female 
3:40 Male 
3:43 Female......... Brooded 
3:48 Male 
3:52 1 A eaten. gece: Ci Female......... Brooded 
3:53 Ka Male 
4:02 3 Male 
4:10 1 t bAten, 22S Fe Male 
4:17 Male 
4:20 1 3 Fomale sais Brooded 
4:25 3 > Male 
4:43 1 18 Porale. (2% cs! Brooded 
hit 1 . 

: SiMe es is ae dies ina et vee 
5:03 1 $ WONG. vcs sx is Brooded 
5:04 Female......... Brooded 
6:54* Male 
6:55 1 Male 
7:00 5 jE eS aaa neon Niro Pe ecg ewe nt 


tex tat seed and fifty minutes interval just preceding for the daily tabulation of other 
NOTE: After 2:21 adical change of temperature took place. The 

reached a maximum of 8 Y Seeres e F. fell imm ately thereafter 27 degrees Bifteen minutes and 

35 degrees within an ‘cr (the | er 929 fall, for so brief a time, in the Chicago region). This i 

accounts fort = “pbk. ag brooding of the female from 3:43 p.m. and the disproportionate f 


ngs in favo 
11 hours 46 minutes 


wet econ pe footing Gan rye re ESC Ey Ook 13 hours 36 minutes 
Total pr ie of obeeroed § 
Total number of feedings, est denntetlcs cits fe ees 17 
oo of peak feedings female 69 
Number of o a Be Ry Perea ee oi a 
verage interval between feedings .........-----+++-55 i 
Ave’ interval with both sexes feeding regularly (9:12 i 
A.M. to 3:43 P.M.) ..... : BPs aie og 5,5 minutes 
RL eer eenkeess se cine wipe Oo adm aie 
Average intervals of feedings of male when he was feed- : 
ing nearly alone (3:40 to 5:01 P.M. ) Sool it aad 10.0 minutes 
Average in’ between y female from her : 
first feeding to her last (5:14 A. DY S04 P. Ma 2s. 10.28 minutes 
Average in’ een feedi male from his first : 
feeding to his last (9:12 A.M. to Je 0 Pi De sc encaduy 12.25 cm 
Shortest interval between ee 50 minu 
interval between feedings.....-.-..-+.--++++5+ 32.00 minutes 
Total number of rg on emale eatin cc each | 
period with no as one ne nesting ee Hd 


Total number of young fed by male. 


96 Trans. Acad. Sci. of St. Louis 


assist. Apparently the only other record of rate of feeding visits 
is that of Dibble (1900) who recorded twenty visits in an hour. 

Food of nestlings.—Here is a field where more investigation 
would be profitable. General notions as regards the type of 
food are available but quantitative studies, of any extensive 
scope, are non-existant. I have identified the following food 
being carried to nestlings: Lepidopterous larvae (chiefly ‘‘cut- 
worms’’), earthworms (very frequently), grasshoppers, moths 
and seeds of Setaria. What little weed seed nestlings receive is 
given them in March and April, earthworms are favorites in 
April, cutworms in March, grasshoppers in June and July. 

A few nestlings that had died of exposure in late March and 
April were collected and it was surprising to find their stomachs 
fairly well filled with food, as follows: 


1. March nestling. 
RHE INACEOR es os oe ua SS eee ae cae bee wd 100% 
WORE DUDA Se as eee 30% 
MSOULIO TURE INGNU oe vs ernie cs a es 10% 
2. March nestling. 
MIRC ALOR ee a in Ae ek 100% 
One “‘c EOE eis ae ew Lee as 10% 
eetis (races. es sy eo i ks 30% 
3. March nestling. 
OR EE ns ey ies es ee 100% 
“cut worms”... <. Oe ee cae bb i oa 10% 
CHG TV PUDATIUN oss ies rev li ake 5% 
Heetie: trapmette oo... ce 25% 


4. April nestling, 

MGSIAT IRANI a cs ks ee 100% 
All beetle fragments, 

MecAtee (1905) examined stomachs of ten nestlings, found 
that those obtained earliest and in northern states contained the 
largest amount of vegetable matter. A New York nestling had 
been fed 45 per cent whole wheat grains. Among the vegetable 
matter was green foxtail (Chaetochloa viridis), tumble weed 
(Amaranthus), and yellow sorrel (Oxalis stricta). The grass- 
hoppers predominated in the animal matter, 41.5 per cent of all 
the food. Weevils came next. Other insects were wire Worms 
(Elateridae), white grubs (Scarabaeidae ), leaf beetles (Chry- 
somelidae), and pill beetles (Byrrhidae }. 

e of the most interesting things in connection with the food 
of nestlings is the method the parents, especially the female, 
employs in getting it. Much of it is dug up somewhat in the 


Reproduction 97 


manner in which a Robin secures earthworms. Thus I have seen 
the Larks dig up both cutworms and earthworms. MeAtee 
(1905) quotes a correspondent in regard to this method of 
securing cutworms for the young. This correspondent, Dr. 
Le Baron, recounts the description of a farmer who watched the 
Lark pry out cutworms from beside the hills of corn, seeming 
to know, by some method, just where they were to be found, 
and taking one after another until four or five had been secured 
before leaving for the nest. Criddle (1920) describes a similar 
method used by praticola in Manitoba though in this ease the 
cutworms were secured from the sides of scattered clumps of 
weeds. 


Reactions of adults with young in nest.—The surprising 
thing in the reactions of the Larks at this period is not that 
they are so different from the reactions when eggs are in the 
nest but that the reactions are so similar. The female does 
much brooding during the first few days (especially in the case 
of early nests) following hatching and her solicitude is expressed 
in a fashion very similar to that exhibited during incubation. 
Later she does more calling, stays nearer, gives fewer casual 
abandonments. One female would invariably fly close above 
my head as I approached her nestlings, then as I sat near the 
nest she would stay near me and hunt for food within twenty 
to thirty feet and always, under such circumstances, approached 
the nest with great hesitancy. Again another went up into the 
air while I was by her nest and flew about for several minutes 
three or four hundred feet overhead and in circles two or three 
hundred yards in diameter. During this time she made not a 
sound. But these reactions were exceptional. Tables 11 and 13 
give a summary of reactions of adults when young were in the 
nest. Casual abandonments and distress simulations persist but 
‘‘other reactions,”’ i. e., calls, flights above the nest, have greatly 
increased. The male shows concern for the first time after the 
eggs hatch, but then it is confined to calls. His solicitude for 
safety of the young is frequently non-existant. In such cases, 
if he is not timid, he will feed unconcernedly while an intruder 
is within a few feet, though the female with her highly devel- 
oped concealing instincts may not approach the nest. If the 
male is timid he merely stays away from the vicinity until the 
intruder leaves. 


98 Trans. Acad. Sci. of St. Louis 


Nest cleaning —One of the most peculiar and at the same 
time most highly developed of instincts is that of nest sanitation. 
So highly developed it is that frequently it inhibits instincts of 
protection solicitude. Thus at one time a female was coaxing 
the last of her young from the nest, away from my presence, 
when she spied excreta in the empty nest. She promptly 
deserted her nestling, leaving it there near me, the offending 
enemy, picked up that dropping and flew away with it. Drop- 
pings carried away were usually removed fifty to one hundred 
feet, deposited, and the bill whetted thoroughly afterward. They 
could not be left near the nest. On one occasion the male flew 
up to an old cabbage stump near the nest with a bolus of 
excreta (Plate XXIX, Fig. 1). My camera shutter, trained on 
the stump, surprised him into dropping his burden. That acci- 
dent inhibited his alarm, however, for he hopped down among 
the weeds at the base of the cabbage stump, hunted for a 
moment, found his dropping, then flew off with it. In March 
and April nearly all excreta was eaten by the adults; in June 
and July nearly all was carried away and dropped. There is 
here, very probably, a close connection between the variation in 
this habit in the various seasons, and the available food supply. 

Developmental reactions of the young.—Why young birds 
have no fear at hatching and why this instinct and others should 
suddenly appear in them at a surprisingly definite period, can- 
not be fully explained. It is instinctive certainly, lying dormant 
however until the physical state of the nestling can carry out, 
logically, its promptings. The Larks reach the age of discrim- 
ination about twenty-four hours after their eyes are open, that 
is, on the fifth or sixth day. Prior to that time they will respond, 
i. @., Open their mouths, at any sound, especially a whistle. 
Failure to respond, or discrimination, is not an instantaneous 
acquisition but becomes noticeable over a period of one or two 
days, at times three or four. Shortly after discrimination be- 
comes apparent in the young they learn to withdraw at the touch 
of a hand and also there is the first evidence of an instinet for 
concealment, for then they remain wonderfully quiet in the nest. 
Also at this time, the seventh to ninth day, they learn the 
crouch-concealment for, upon being removed from the nest, they 
sit quietly upon any object upon which they may be placed 
though at any younger age they will struggle and wriggle 


Reproduction 99 


Fear—stark, blatant, naked—does not disclose itself until the 
young are near nest-leaving age. This is a wise provision of 
nature certainly for otherwise fear would drive them from the 
nest at the approach of an alarming object before the proper 
time. Indeed fear and nest-leaving seem to be co-operative. I 
have noted that a nestling, a few hours prior to nest-leaving, 
would sit quietly in the hand, but a short time later, with the 
first trial of the legs outside the nest, would, when captured, 
struggle violently and squeal piteously. Having found their legs 
they also find the desire to use them for escape. Disease, starva- 
tion, improper development all retard this psychical growth. 
Thus one entire set, improperly nourished, responded up to the 
ninth day. In many nests one or more nestlings would, because 
they were from a few hours to a day younger, show a greatly 
retarded physical and psychical development from two to three 
days behind their more fortunate brethren. This was a result of 
the method of feeding (to be taken up later), whereby an advan- 
tage in age would permit the older young to secure most of the 
food (see Plates XXIII to XXVIII, inclusive). 

Growth of the young.—Rather extensive data, collected in 
this field, have been reduced to tables and curves (Tables 18, 


TABLE 18 : 
Growth in grams of an April set of Prairie Horned Lark nestlings to nest 
leaving, Ithaca, N. Y., 1927. 


Nestling No. 1 2 3 : 
deed oS 3.4 3.0 3.0 hae 
Sete 4.1 3.8 3.6 2.6 
nk eS 5.0 5.0 3.7 (lost) 2,3 dam) 
Fae cai a, MOE ere a tan G1 7.2 
nei ete ee ee 8.7 8.3 
Apa 26. 9.9 10.4 
Fe aig Ri pee ne 11.2 9.0 (dead) 

Mme ge eT eee 13.2 
RMS 14.2 
BOR Oe Ci cs 16.3 
WN Tis 17.0 
og, PE ee 18.1 
Av. daily increase. 1.33 0.98 0.80 0.20 


100 Trans. Acad. Sci. of St. Louis 


19, 20, 21, Figures 12, 13, 14, 15, 16, 17), and a brief summary 
only will be given here. There are but two or three measure- 
ments that have significance, as far as I can see, and these only 
have been considered, i. e., weight, total length, length of tail 
and length of flight feathers. 

The weight of the egg near hatching averaged 2.85 grams. 
As might be expected the newly hatched Larks were a little less 
than this, but so promptly are they fed that very few first 
weighings were made before the young were able to show a 


100 


’ 
rest}ing lees 


“ pestiing lose 
of plus egg ices 


egg i088 


March April wey June dely 
Figure it 


Fig. 11. Loss of eggs and nestlings of the Prairie Horned Lark dur- 
ing the 1926 nesting season at Evanston, Ill., in per cents per 


considerable increase over the ege weight. Growth is uniform, 
both in weight and length, until the approach of the seventh 
day. At this time the rapid, very general unsheathing of the 
feathers causes a check in weight growth. Indeed a loss is shown 
where weighings were made late on the seventh day and early 
on the eighth (see Figure 13). The Cowbird nest-mate of one 
Lark nestling was still in pin-feathers at this period and does 
not show this straightening in the curve (see Figure 15). The 
April nestling developed so slowly that this straightening in the 
curve in its case (see Figure 12) is not apparent. As might 


eon 


Reproduction 101 


expected, growth in length shows no lessening between the sixth 
and eighth days but rather an acceleration (see Figure 14). 
This is due to the advent of the tail. The retarded or lost young 
noted in the figures are, for the most part, the result of starva- 
tion through poor feedings and scanty food supply. The poor 
showing of the April nestling (see Figure 12) is an exaggeration 
of the situation that prevailed (though usually to a less degree) 
in most April nests. It is the result of two things: (1) pre- 
vailing low temperature and the consequent necessity of much 


Figvro 12 


7 a : : 7 7 3 a 
Fig. 12. Growth in weight of an April set of Prairie Horned — 
nestlings (nest By, April 21 to May 2, inclusive, Ithaca, N. Y., 
1927), 


brooding, hence lessened feedings (see Figure 16) and, (2) an 
apparent lower supply of food. 

Attention should be called to one more point. In the general 
averages (Table 21) the lessened growth in weight and lessened 
increase in length between the tenth and twelfth days is due to 
the fact that birds in the nest at these ages are almost certain 
to be those retarded or improperly nourished, the most pros- 
Perous having gone on the tenth. 

Descriptions of young at various ages——The young in ju- 
venile plumage have been described repeatedly, but apparently 


42 


TABLE 19 


The Growth of a May set of Prairie Horned Lark ag from day of hatching to 


nest-leaving, Ithaca, N. Y., 192 


Weight (in grams) Length (in centimeters) 

Nestling No 1 2 3 4 5 1 2 3 4 5 

May 6 3.5 3.4 3.5 3.2 2.3 5.0 5.0 5.0 4.8 4.5 
May 7 4.9 4.6 5.3 4.0 3.1 5.8 5.6 5.8 5.1 5.0 
May 8 44 5.7 7.0 5.8 3.6 6.7 6.1 6.6 5.8 5.5 
May 9 9.2 8.3 9.0 6.3 4.7 7.2 Ut Vik 6.1 5.6 
May 10 10.0 10.8 12.4 lost 5.8 7.4 7.5 12 lost 6.1 
May 11 13.9 14.1 SO se bea ws 6.0 7.8 7.8 Bele Es ee hes 6.1 
May 12 19.9 18.6 i VR Gar | Eee arian 9.0 8.9 8.6 Se ve ewes 7.4 
May 13. 19.2 18.0 CA Gd Seno ar rae 9.4 9.6 9.6 se: See eres Rea 7.6 
May 14 22.1 21.5 Bei veins 6 10.3 10.4 10.2 pl pe ag eee es 8.0 
BN oes sk cee eek ee sae ees 22.6 A Poe e i 10.5 8.0 
Average daily increase......... 2.42 2.02 2.06 1.03 1.02 .67 .61 65 42 388 


é0T 


T 38 fo ‘wg ‘poy ‘suo4y 


sino 


Sram 


Reproduction 103 


no careful description has been given of natal down. This 
down, in the case of the Larks, is unusually heavy and so serves 
as a protection against the sun from which they are rarely 
Shielded and of a color that has remarkable concealing value. 
The color of the down is cream-buff (from Ridgway’s, 1912, 
“Color Standards and Nomenclature”) and is distributed in 
the following tracts: a double patch (i. e. one on either side), 
on the crown, a double tuft on the occiput, a strip along the 


Figure 13 


a 


3 2 3 4 6 6 7 8 r) 10 


Fig. 13. Growth in weight of a May set of Prairie se hac 
hestlings (nest C;, May 6 to 15, inclusive, Ithaca, NN: Y,, 19 di 


humerus, a strip along the arm, at the tips of the greater coverts 
of the secondaries, a strip on either side of the spinal column 
from below the wings to the tail, and, lastly, a femoral tuft. 
The development of feathers depends entirely upon growth 
in weight, that is, upon amount of food. The deseriptions here 
will be of a normal or optimum development. On the third day 
Pterylae were mapped out on the side of the breast and abdomen, 
in small close-set whitish dots. Pterylae in fine quill tips 


104 Trans. Acad. Sci. of St. Louis 


appeared on back, wings and head, fourth day. On the fifth 
day primary quills were 1.5 mm. long; breast quills .7 mm. long. 
On the sixth day primaries were 7.5 mm. long; feathers of the 
head, back and breast began to unsheath. Down began to shed 
on the seventh day, when primaries were 1.2 cm. long and un- 
sheathing at the tip. Down was rapidly disappearing on the 
eighth day; the tail feathers protruded .15 cm. beyond the end 
of the body ; longest primaries were 1.6 cm. long and unsheathed 


cont iseters 
u 


Figure 14 

“ / ; 7 Sl ee era 

pk 2 8 ‘ 8 ‘ ? @ ° ” 

Fig. 14. Growth in length of a May set of Prairie Horned Lark nest- 
lings (nest C,, May 6 to 15, inclusive, Ithaca, N. Y., 1927). 


-30 cm. On the ninth day a few bits of down still remained; the 
longest primary was 2.4 em. and unsheathed .8 em.; tail was - 

em. On the tenth day the longest primary was 2.88 em., ope? 
‘9 cm.; the tail was 1.12 em. long. The plumage was n0W 
essentially that of the matured juvenile: down practically off, 
plumage of upper surface black, each feather with a curious 
triangle of brown at its tip. The lower surface was white except 
the throat. A fifteen-day-old Lark, captured by strenuous run- 


Reproduction 105 


ning, presented an appearance no different from this except in 
size (Plate X 

Enemies—Tables of mortality have been prepared which 
give, as far as known, the enemies of nestling Larks as well as 
percentages of loss by season (Tables 22, 23, 24 and Figure 11). 
Enemies early in the season are meteorlogical plus a scanty food 
supply and uneven feeding. Criddle (1920) maintains that early 
nests in Manitoba rarely raise more than one nestling. This is 
in essential accord with the writer’s observations at Evanston 
and at Ithaca. Later enemies are predacious animals chiefly 
and these apparently beset the nestling after heavy vegetation 
has encroached upon the nestling site and so has given the 


TABLE 20 
Growth of a June Prairie a Lark nestling and its Cowbird nest-mate, 
to nest leaving, Evanston, IIl., 1926. 


Weight (in grams ) Length (in centimeters) 


Lark (hatched Cowbird Lark Cowbird 
Seen Kee ae oe June 8) 
gHUe Ge cee 4.1 2.3 
Tne Hh: 6.3 4.5 6.5 5.1 
pe He 10.0 6.6 6.2 5.8 
ee. oe 13.3 9.4 7.0 6.3 
don cack ene Ono 16.6 12.6 7.4 7.1 
muah, oe gee 17.0 14.0 7.6 7.2 
we 17.1 15.3 8.0 7.5 
dnc gt PP eR Oe 20.3 16.8 8.8 7.6 
WUE co G aL -7 18.4 9.2 8.0 
Av. daily increase... . 2.8 2.01 53 41 
nin an RCUSTNC a 


skulkers easy access under cover. The optimum season lies 
between late April and mid-May when weather is more lenient 
but the barren conditions still unaltered. Perhaps the predilec- 
tion of the Lark for open, unobstructed nesting sites has been 
evolved through this protective advantage to the young. 

The loss through improper feeding lies in the fact that incuba- 
tion is begun so frequently before the set is complete; the last 
young to hatch then are at a disadvantage as regards position, 
for they are forced to the rear of the nest. The larger, in front, 


106 Trans. Acad. Sci. of St. Louis 


receive the food; the younger, in the rear, starve, slowly, to 

eath. Later, when food is abundant, there is a sufficient ex- 
cess to pull the younger through. Then, too, more frequently 
in the later season, the set is often completed before incubation 
is begun. 

Parasites were noted in one case only. This was a nest heavily 
infested with mites. The young here developed normally how- 
ever. 

The Cowbird and the Lark—One case of Cowbird parasit- 
ism occurred in early June at Evanston (Plate XVII, Fig. 2; 


rm 
ss 
20 4 
PJ 
10 
64 
Figure 15 eon Oa kaa 
dey 7 3 ) ; z 7 ; 3 * af 


Fig. 15. Growth in weight of a June Prairie Horned Lark nestling 
and its Cowbird nestmates (nest No. 20, June 8 to 17, inclusive, 
Evanston, Il, 1926). 


Plate XXXII). The nest contained three Lark eggs and two 
Cowbird eggs. In this case one Lark hatched a day before the 
first Cowbird, the second Cowbird hatched on the third day and 
the remaining Lark eggs failed to hatch. This one-day advan- 
tage in age in the case of the Lark may explain why it developed 
so normally in spite of the parasitism (see Table 20 and Figure 
15). But perhaps also the Lark may not be a proper host. At 


TABLE 21 
Daily Growth of the Prairie Horned Lark 


Days No. No. Min. Max. | Average |Average| No. No. Max. verage | Average | Average pd toot 
Old | Weighed! Broods | Weight | Weight | Weight | Increase |Measured| Broods Total Total Teta Increase} Length un- 
Length | Length | Length Tail re sheathed 
mary 
1 19 5 2.3 3.8 Bie tive reece 10 3 4.0 5.0 A EI CAP a nan, SUN CRUMIR GIRS, WaMUn ees Lans SE iti dn Neen 
2 20 6 2.6 5.9 4.57 1.36 il 3 4.7 5.8 5.20 ORE yee he hos eee ca sees . 
3 18 6 3.6 8.6 6.36 1.79 15 5 5.5 6.7 5.96 Be (San tops NI 
4 13 5 4.7 10.0 8.30 1.94 il 4 5.6 ae 6.38 Sa Red Pe POE esta sae ‘ 
5 10 5 5.8 13.6 10.66 2.36 9 4 6.1 7.5 6.91 Oar Russ cece’. oy? eae ee : 
6 7 3 6.0 16.6 12.48 1,82 es 3 6.1 8.1 7.34 ee By eres ATi! gay Sane aye ue 
7 6 3 9.0 19.9 15.58 3.10 7 3 te 8.9 8.02 .68 .10 .15 .30 
8 6 3 9.4 19.2 15.65 .07 7 3 7.6 9.6 8.61 .59 27 1.50 .43 
9 6 3 10.3 22.1 18.06 2,41 7 3 8.0 10.3 9.32 ath -63 2.30 . 66 
10 A 3 11.5 22.6 35.09 os 4 3 8.0 10.5 OOO fie heen .83 2.50 .86 
ll 2 2 17.0 22.0 m6 st Diet a ECS ae 1 1 ct Bg EAR sia age Til 3.49 1.74 
12 1 1 BAG ricer eek 0 
15 0 | Z 1 Des O eas 2.50 B80 Se sans 
Weight in grams; lengt] 


h in centimeters. 


wou onpo.daay 


L0L 


108 Trans. Acad. Sci. of St. Louts 


the end of ten days the Lark left the nest normally, but the 
Cowbird was still far behind the Lark in development. The 
following day the nest was empty and the ultimate fate of the 
Cowbird is not known. Space does not permit an extensive 
speculation as to why the Prairie Horned Lark is not more fre- 
quently parasitized but a few points may be noted: 

1. The Lark is not as small as the usual host and there was 
but little diserepaney in egg weights (Cowbird 3.12, Lark 2.65 
grams). 


gram ¥, 
bal 6B, 


Fiqure 16 
OEE Ueeemacver cemueesnee eee A Lee AN eee 
daye 2 3 Pe . ~ P rv 13 


June Prairie Horned Lark nestlings with curves of the meat 
daily temperatures of the same periods (nests Bo, April 21 “4 
May 2, inclusive, Ithaca; C;, May 6 to 15, inclusive, Ithaca; and 
No. 20, June 8 to 17, inclusive, Evanston). 


2. Fully half of the nesting season of the Lark is prior to 
sexual maturity of the Cowbird in the spring. 

. _The incubation period may not be such as to favor 
s : 
4. The exposed condition of the nest may be detrimental to 
the scantily downed Cowbird. 


Reproduction 109 


5. In the case noted the Lark eggs (or at least egg) was laid 
before the Cowbird, apparently, and incubation may have begun 
then. 

6. The food, in June at least, is favorable, however. At 
Ithaca I placed a newly hatched Cowbird in a nest with Lark 
eggs. The Cowbird prospered and when removed ten days later 
was well developed and weighed 21.7 grams, about the weight 
of a Lark at that age. However, young Larks would have gone 
from the nest at this age but the Cowbird was not yet ready to 
do so. 


Grane and 
contineters 
z= 
I} 
= growth in total length 
i 
growth in lengta 
minus tail 
6 
Figure 17 
tn = 3 oe ae Bae’ ee 10 <« & 36 


Fig. 17. Average growth in hen and length of a varying number 
of Prairie Horned Lark y 


7. The Horned Lark has no aversion to foreign eggs for a 
Song Sparrow egg, placed with Lark eggs, was not disturbed. 

Here, then, seems to be a possible host that for reasons not 
quite clear the Cowbird almost wholly overlooks. 

Protection for the young.—As birds of the open, and on 
the ground, the young of the Larks have need for two important 
features to protect them: silence, and the proper coloration. 
These two characteristics they possess in remarkable degree. At 


TABLE 22 
Mortality table of nestings of the Prairie Horned Lark for 1926 at Evanston, Ill. 
. * No. of Egg No. of | Nestli Successful 
Nest No Inclusive Dates Eggs Toss Cause Nestlings Bg Cause Nestlings 
L ee 2 2 Sno 0 ) 
2 ea 228. . 2 2 Sno 0 0 
3 April lio Ve ee : Failure to hatch......... : 2 Disease 1 Starvation 1.. 
t Apel 12—May ) j 0 7 
i] April 12—May 4............ fe Or ra aed bio w aed 4 
April 12—April 27 3 UGROOWI vii cose oak ( 
j April 13 MYO cts hited 6 te ee 2 Gtarvation cies cscs 7 
3 April 183—<April Unknown ( 
) April 18—May 7 MR so das bras 0 : 
) April 13—May 0 1 SM WOMION cs kak osc es es 
April 14—May £ Failure to hatch......... 1 WGENOW ss hikes hs 
April 14—May fdas, Roel Tag le nee aon a eee 
3 April 26—May 20 0 
ae 27—May 19 d d 1 Starvation 
ay 83—May 24.............] 1 DEN ss RG LS 
May 7—May 9......-++++- Unknown ( 
May 9—June 2 3 0 
3 May 21—June 12........... Ne Ne ale Gy as pan CER Cee kee 
) May 22-—June 7... ...-¢+95. Kies 5 Unknown 
) May 25—June 17............ Failure to hatch......... Rese) Sodeepaae 
June 9—June 26............ Failure to hatch......... 4 4 1? 0 
2 June 17—July 11............ Br i es eo aa al eed rane 4 1 Unknown 3 
3 June 22—July 5.0... ek Failure to hatch......... 1 Unknown 0 
t June 27—July 12...........> 4 Failure to hatch......... 3 3 Unkuowie 6 oiisie kee be ) 
Total 82 3 9 65 26 39 


| 
*The first date in each case indicates date abe egg is laid, this date is estimated 
Sum geet cent of loss in eggs: is 
cent o nestling loss ng ee od be aoa: 40 
Per cent of loss of whol Beet hatching 
Per cent total loss of 82. eggs: 52.4 


OIT 


T 18 fo “wy ‘poopy ‘suDiy 


sino 


TABLE 23 
Mortality table by months of nestings of the Prairie Horned Lark at Evanston, IIl., 1926 


No. of 
Per Cent Nestlings Nestling P N Cent of | Total No. Total Loss Per Cent 
Egg Loss om Eggs and Eggs and 

Month gas Within of Egg Loss Bape Loss Nestlings Nestlings Total Loss 
March 4 4 1,000 0 0 0 4 4 1.000 
April 44 9 . 204 30 6 . 200 74 15 . 202 
May 28 3 .107 23 6 . 260 51 9 .176 
June 26 3 115 20 9 .450 46 12 . 260 
July 6 2 .333 8 5 625 14 7 . 500 

TABLE 24 
Mortality table of nestings of the Prairie Horned Lark for 1927 at Ithaca, N. Y. 
Nest No, Inclusive Dates* phy fez Cause seni ci phe: Cause + she 

Bi March 15—31 | 3 0 | 3 3 Low temperature........| 0 
Ai March 19—April 1.......... 2 2 Snow 0 0 
B2 April 8—-May 2.........058. 4 0 4 3 Low temperature 1 
Dd April 8—April 19............ 3 3 Cultivation 0 
Cc April 21—May 15........... 5 0 5 2 Unknown 1, Expos.1... 3 
As April 22—May 16........... 3 0 | | 3 0 a 
Total | 20 5 | | 15 | 8 7 


*First date in each case is estimated. 


uoyonpo.day 


IIl 


112 Trans. Acad. Sci. of St. Louis 


no time does the young Lark have an audible food call (such as 
the continual clamor of young Cowbirds or young Baltimore 
Orioles, for instance), except when the parents are directly at 
the nest. Even then it is not audible more than a few feet away. 
In all plumages the young are remarkably concealed whether 
it be their clay-colored down or their mottled juvenile plumage, 
which is such a remarkable ‘‘picture pattern’’ of the lights and 
shadows about a ground nest (Plate X XXIII). 

The actions of the parents, especially abandonment conceal- 
ment and a stern reluctance to approach a nest in which there 
are young, are well calculated to protect ground nests. 

Nest leaving—The age of the young at nest-leaving de- 
pends upon the manner and amount of food they have received. 
The average is between the tenth and eleventh day. Some go 
on the ninth, one set remained until the fourteenth. They 0, 
usually, merely by following a parent who has just brought them 

ood. In one case I observed the female entice a belated young- 
ster from the nest by coming up with food and retreating until 
his hunger forced him out. 

Just prior to nest leaving, as has been noted, the young 
acquire a ‘‘crouch-concealment’’ habit that stands them in good 
stead once they are away from the nest. This crouch or ‘‘freeze”’ 
is maintained at all times, when the parents are not near, up t0 
five or six days after nest-leaving (Plate XXXIV). If they are 
disturbed when in this ‘‘crouch-concealment’’ they will not 
return to it unless left for a moment with one of the parents. 
This habit, plus their peculiar plumage, makes the Lark similar 
to the precocial young of a gallinaceous bird as Chapman (1918) 
has noted. Indeed the Larks are semiprecocial in many Te 
spects, not the least of which is the habit of leaving the nest 
several days before they can fly. 

any writers have noted that the young Larks leave the nest 
before they can fly and Forbush (1911) sets this time at a week. 
This is a little too long however. By banding the young I was 
able to get some definite material on this. Thus one young Was 
caught, able to make flights of about one hundred yards, at 
fifteen days of age. This one had been out of the nest just five 
days. 

The parents must find their quiet youngsters, in their crouch- 
concealment, by some method other than sound. To do 


Reproduction 113 


they hover in a peculiar fashion here and there until the crouch- 
ing Lark is seen. 

One other matter of interest with regard to recent nestlings 
remains to be noted. That is that the young hop, do not walk. 
Apparently Brooks (1908), is the only other writer who has 
noticed this. It may be a recapitulatory feature harking back 
to a hopping ancestor or, more likely, it is merely an anatomical 
defect in the young which has no ancestral relationship. In any 
ease walking is not learned for several days and when first 
attempted is a slow waddle with legs spread widely. Rapid 
locomotion for many days is accomplished by hopping. One of 
my most trenchant recollections of the Larks is of a female mov- 
ing rapidly off down an old wheel rut and running, with a young 
Lark following and going just as rapidly as she—but hopping. 


MOLT. 


Activities subsequent to nesting have been taken up in a gen- 
eral way under fall and winter activities. A word or two re- 
Mains to be said of molt. Dwight (1890) was, it seems, the 
first to show that the transition from the juvenile plumage to 
the adult is accomplished by a complete molt of wings and tail 
as well as body feathers. This molt, in the case of praticola 
occurs between late July and late August. Dwight also brought 
out the fact that there is but one molt in the year for adults 
too, the post-nuptual. Breeding plumage comes about by the 
Wearing off in late winter of the brown tips that obscure the 
black areas of crown, cheek and throat. 


ECOLOGY OF THE NESTING-SITE OF THE PRAIRIE 
HORNED LARK IN RELATION TO OTHER 
BREEDING BIRDS AT EVANSTON, ILL. 


At Ithaca, N. Y., because of the comparative uniformity of the 
conditions of the breeding area, there was not presented the 
opportunity, as at Evanston, IIl., of observing a large number 
of other breeding birds near at hand. As a matter of fact the 
Situation at Evanston was unique in that the subdivided golf 
course with its torn street-ways, old hazards, grass and meadow 
areas and weed patches, all allowed now to proceed uninter- 


114 Trans. Acad. Sci. of St. Louts 


ruptedly, produced a veritable gamut of ecological conditions 
during spring and summer which proved suitable to a long 
series of birds. Since the flora, here otherwise undisturbed, was 
modified with the advance of season, it follows that the ecological 
categories of the open field were modified likewise and were 
followed, as a consequence, by a change of population wherein 
the Prairie Horned Lark figured conspicuously. 


Because opportunity was presented thus so ideally to make 
close comparisons between Lark and its open field congeners, 
this treatise will not be complete’ without so comparing. The 
Lark began to nest in March with flora at its minimum and 
suitable breeding territory extensive, and continued to nest 

into July when flora was at its maximum and suitable areas 
greatly reduced. Such a change closed some territories com- 
pletely and greatly modified others. But what was unsuitable 
for Larks proved highly acceptable to others and it is this suc- 
cession that interests us here. This succession was both seasonal 
and, in June, geographical. For instance, a region might satisfy, 
with its seasonal conditions, the Lark in March and April, the 
Vesper Sparrow in May and the Dicksissal in June. Such con- 
ditions were frequently presented at Evanston. Likewise, at @ 
single period in June, the same sequence would be presented by 
walking from an old sanded hazard to a neighboring weed patch. 

In addition to ecology of habitat the dates of arrival, seasons 
of song and other characteristics of interest are given and 
reference made back in each case to the Prairie Horned Lark, 
our main thesis. This material can be presented best by con- 
sidering the species separately. 

Bartramia longicauda. Upland Plover. Notes of this bird 
were heard on the main subdivision June 17, 1925. In 1926 
they were first heard in April 21, and almost daily thereafter 
until May 8, when a peculiar interval occurred with no records. 
They were noted again on May 30 and with one or two excep- 
tions were seen or heard daily until July 22, the last visit to 
the area. 


On April 26 that most astounding weird and mournful wail 
(song), of the Plover was first heard and frequently from that 
time to July 12. 


On June 18 a nest with three eggs was found in the timothy 


Ecology of the Nesting-Site 115 


just. northeast of the Main Subdivision. One of these eggs 
hatched July 4, the other two, though fertile, failed to hatch. 

Extensive data were collected concerning ealls, song and 
breeding reactions but space does not permit their inclusion 
here. There were two or three pairs of these interesting birds 
in the vicinity and it is possible that one pair may have nested 
on the Main Subdivision. The musical calls of these birds to- 
gether with their uncanny song provided an atmosphere well in 
keeping with the open areas where the Prairie Horned Lark 
was also at home. The nesting habitat was that of comparatively 
tall, close-set, uniform timothy. 

Actitis macularia. Spotted Sandpiper. Arrived April 30, 
1926, but did not appear on the subdivision until May 22. A 
puddle there then, formed by late May rains, proved an attrac- 
tion for several days. A pair nested in block No. 19 not ten 
feet from the sparrow trap that I visited daily. The nest was 
found June 6 (first day of incubation, I believe), the eggs 
hatched June 25: an incubation period of twenty days. These 
young, with their parent, remained on or near the subdivision 
until July 17. 

The nesting habitat was in sparse but coarse weeds such as 
evening primrose (Oenothera biennis), white sweet clover 
(Melilotus alba), Mare’s tail (Hippuris vulgaris), wild lettuce 
(Lactuca sp.) and squirrel tail grass or wild barley (Hordeum 
jubatum). 

Oxyechus vociferous vociferous. Killdeer. The Killdeer came 
March 19 and was a conspicuous element in the bird life of the 
subdivision from that date to late July. Though they were 
there daily none actually bred on the Main Subdivision but 
rather seemed to use it as a feeding ground. However one nest 
was located on the West Subdivision, July 6; subsequently de- 
stroyed by a mower, July 15. It was located in the old vegetable 
garden, in an area of bare ground with sparse young weeds, such 
as Chenopodium, Xanthium and Setaria, beside a small plant of 
wild lettuce (Lactuca canadensis). 

Dolichonyx oryzivorus. Bobolink. Came on May 8, 1926. 
One was taken in my sparrow trap on May 14. On May 16 
they were present in numbers and in riotous song and from that 
time on formed the most conspicuous living element of the 
subdivisions. A second was taken in the trap May 21, the first 


116 Trans. Acad.’ Sci. of St. Louis 


female was seen May 22, maximum numbers seemed to be 
reached May 23. Not one of the daily visits from June 1 to late 
July failed to disclose Bobolinks, they could not be overlooked. 


From the time of their arrival until the young hatched, fe- 
males seem to be almost non-existant. They are as seclusive as 
their males are obvious. Nests with eggs are almost impossible 
to find for the brooding birds either do not fiush from them 
under any circumstances or slip off through the dense grass at 
the approach of the searcher. Rope dragging over most of the 
Main Subdivision in June, did not locate a nest definitely. 


The female comes to the weed tops with the hatching of her 
young and her sharp ‘‘chink, chink’’ is sign of a nest near. 
By observing a female with food one nest was located June 18 
(not on subdivision) with three eggs and three newly hatched 
young. Another (on the Main Subdivision) was found on July 
17 with young near nest-leaving age. 

The great fervor of song from the males begins to abate after 
the first week of July and gradually the quieted adults and 
young disappear from the breeding ground. In 1926, the breed- 
ing birds were reduced to two or three pairs, by July 9, and 
from then on there were fewer songs than formerly. Even these 
few songs were still further reduced on subsequent July visits 
until on July 21 the last birds noted were adults carrying food 
to belated nestlings, quiet now except for scolding notes. On 
July 29, 1925, large flocks of Bobolinks collected on the weedier 
parts of the subdivision (in patches of Oenothera, Melilotus, 
Ambrosia and Cirsium) and, though the majority of these were 
young birds, a goodly number of adult males were with them in 
various stages ae —_— Their only note now was a pleasantly 
metallic ‘‘chink 


A census of a. males showed fourteen pairs of breeding 
birds on the Main Subdivision (about 90 acres), in mid-June. 
Each of these had a definite territory which any male would 
sharply delimit if he were persistently driven from place to 
place. One such territory was roughly rectangular, sixty by 
ninety yards, about the size of territory of the Lark. Yet the 
males, in their exuberance, frequently flew into each other's 
territory or, if a female appeared, might collect in threes °F 
fours near her. In spite of this the Bobolinks were never ob- 


Ecology of the Nesting-Site 117 


served to fight or to drive away intruders as the Prairie Horned 
Lark did invariably. 

The breeding season and the song of both Larks and Bobolinks 
ended nearly at the same time but the similarity stopped there. 
The Lark, nearly resident, sang from late January to early July, 
bred from March to mid-July, whereas the Bobolinks, highly 
migratory, sang from mid-May to early July, bred from late 
May to mid-July. 

Located nests were in the densest, though not tallest, vegeta- 
tion. One was at the base of a clump of young evening prim- 
rose (Oenothera biennis), another in heavy plantain (Plantago 
major) blue grass (Poa pratensis) and wild strawberry (Frag- 
aria sp.). Thus the Bobolink is near one end of that series of 
ecological habitats of the open field determined by the density 
of vegetation—the Prairie Horned Lark at the other. 


Molothrus ater ater. Cowbird. Though the Cowbird arrived 
on April 16, in 1926, the first did not come onto the subdivision 
until April 30. Thereafter the bird was a frequent member of 
the fauna until June 27, when the last was noted. Females, 
apparently nest hunting, were flushed from the grass on May 
16 and May 26. In addition to the one case of parasitism of 
the Prairie Horned Lark (for which see back), there were also 
noted on the subdivisions one case of parasitism of a Vesper 
Sparrow (Sparrow was seen feeding young Cowbird) and an- 
other of a Song Sparrow (male was seen feeding the young 
Cowbird). 

Sturnella magna magna. Meadowlark. Next to the Bobo- 
links, the Meadowlarks claimed the eye and ear of the observer 
upon the subdivisions. In the fall of 1925 they were seen on 
October 4, 25 and 31. Those observed on October 4 had con- 
gregated in the marsh just south of the subdivision and were 
maintaining a remarkable jargon of experimental song—none 
full, but snatches of the real thing and all birds doing it at 
once. 

In 1926, the first returned March 19 and at the time of the 
great snows of late March many birds were on the barren sub- 
divisions. On April 1, I waded the more than a foot-deep snow 
to find that the Prairie Horned Larks were off their territories, 
off the subdivisions and along the roadside and the Meadowlarks 


118 Trans. Acad. Sci. of St. Louis 


were sitting in sunny pockets of the snow about the cornstalks 
of the West Subdivision—and there singing. 

Meadowlarks were observed every day from early April to 
late July. The maximum number seemed to be reached by April 
28. Three nests were located, one only on the subdivisions. A 
nest of June 11 had three eggs, a nest of June 20 had five eggs 
which hatched June 25, young left the nest July 4 and 5 at an 
age identical to the nest leaving of most of the Prairie Horned 
Lark nestlings. <A nest of July 18 had two young, well-fledged, 
near nest-leaving. On June 23, and subsequently, family groups 
were in evidence. A mid-June census showed seventeen pairs on 
the Main Subdivision. 

By the first week of July songs were fewer and less vigorous 
but were still given occasionally even to the end of the month. 

The breeding habitat of the Meadowlark is that of compar- 
atively low but heavy grasses. Nests seldom occur in dense 
leafy growths of dicotyledonous herbs as do those of the Bobo- 
link and Dicksissel. The one located subdivision nest was in a 
broad expanse of blue grass (Poa pratensis). Thus the Meadow- 
lark, in the relationship of its breeding habitat to vegetation 
comes somewhat between the Dicksissel and Bobolink at one ex- 
treme and the Prairie Horned Lark at the other. 

Pooecetes gramineus gramineus. Vesper Sparrow. On April 
16, 1926, the first definite songs of the Vesper Sparrow occurred 
on the subdivisions. The day following they were numerous, 
and every day from that date until late July they are recorded 
in my notes. 

The Vesper Sparrow remained in full song later than any 
other resident of the area and even on July 21, with nearly all 
other bird voices hushed, his voice still rang out across weed 
and grass tops of the West Subdivision. In broad day and full 
sun the Vesper Sparrow sang in May and June but evening and 
cloudy days found him at his best and fullest. In July the song 
was restricted nearly entirely to the evening. 

One nest was located on the Main Subdivision June 8. It 
contained four eggs of which one hatched July 18, two others 
July 19, and one failed to hatch. The young left the nest June 
28 with one at the eleventh day and two at the tenth. The June 
census showed five pairs of nesting birds on the Main Sub- 
division, nearly all in old hazards. 


Ecology of the Nesting-Site 119 


Of all resident birds of the subdivisions the Vesper Sparrow 
is nearest the Prairie Horned Lark ecologically. The above nest 
was in an old hazard depression of bare ground chiefly, with 
scattered tufts of squirrel tail grass (Hordeum jubatum), and 
red top grass (Agrostis palustris), the only verdure. The nest 
itself was built partially under a little pile of old dead and 
dried weed stems. The Vesper Sparrow thus occupies the 
Sparse weedy regions, regions with trash and much bare ground, 
the nearest approach to the nearly bare open where the Prairie 
Horned Lark nests are found. Thus in the series the Vesper 
Sparrow comes in the second ecological breeding niche that 
starts with the Prairie Horned Lark in the barest of habitats 
and reaches to the Dicksissel in the densest. Another viewpoint 
is of great interest in this connection, in that the locations of 
the ecological niche for both of these birds varied with the sea- 
son. By late June the last breeding areas of the Main Subdi- 
vision had, with the press of summer verdure, become inhos- 
pitable to the Lark and the birds that were still breeding were 
in the more suitable ground of the West Subdivision. For a 
while longer the Vesper Sparrow remained in the Main Sub- 
division but July found it following the Lark—two weeks of 
plant growth behind the former. 

Passerculus sandwichensis savanna. Savannah Sparrow. My 
notes contain a record of this sparrow on October 25, 1925. The 
first definite record for 1926 is April 16, when two were taken 
in the ground trap on the Main Subdivision The first songs 
were heard April 22. Others were taken in the trap May 3, 6, 
9,13, 26. This little sparrow was numerous in the area through- 
out the entire season and was noted daily until July 21 (the last 
regular visit to the region). Songs were frequent until June 18, 
when there was a noticeable letting off probably coincident with 
the hatching of the young. However, singing was maintained 
until the middle of July. The census of mid-June showed nine 
breeding pairs. 

No nests were located in Evanston in spite of the large num- 
ber of breeding birds but the birds preferred the tall heavy 
quack grass (Agropyron repens) and, later, the red-top grass 
(Agrostis palustris). A nest, located at Ithaca, New York, was 
in tall grass of mixed Agropyron repens and Dactylis glome- 
rata (orchard grass) so dense that long searching was necessary 
to find it even though the bird flushed at my very feet. 


120 Trans. Acad. Sci. of St. Louis 


If the Ithaca nest is indicative of the ecological habitat then 
the Savannah Sparrow is fourth in the series from the Prairie 
Horned Lark to the Dicksissel, from the bird breeding in the 
scantiest vegetation to the bird of the heaviest: (1) Prairie 
Horned Lark, (2) Vesper Sparrow, (3) Meadowlark, (4) 
Savannah Sparrow, (5) the Bobolink, (6) Dicksissel. 

Ammodramus savannarum australis. Grasshopper Sparrow. 
A single individual sang on the Main Subdivision April 28, 1926; 
none from that date to May 8; none again until June 1, but the 
Sparrow was noted regularly from this last date until the maxi- 
mum number of singing males seemed to be reached on June 13. 
From that date to July 21 they were noted daily and in song. 
The mid-June census showed twelve breeding pairs on the Main 
Subdivision. 

It may be of interest to note here that these birds have two 
distinct songs: (1) the “click-ik, z-z-z-z-e-e-e-e-’’? described by 
most writers and (2) a ‘‘click-ik, zeah, uhah, zeah, uhah, zeah, 
uhah,’’ or ‘‘click-ik, z-z-z-zwea, Z-Z-7-ZWea, Z-Z-Z-ZWea, buzzing 
and insect-like as the first but interrupted and undulating, to- 
tally distinct from the song ordinarily described. To say ‘‘life’s 
a rigmarole, rigmarole, rigmarole’’ with all the buzz at one’s 
command gives a good notion of the quality of the song. It 
seemed to be given more frequently in the evening, the first more 
frequently during the middle of the day. That it is not a 
peculiarity of northern Illinois Grasshopper Sparrows is shown 
by the fact that an Ithaca, New York, bird knew it also. 

Since no nests were located the ecological habitat cannot be 
definitely assigned. But the birds were found in conditions 
similar to those occupied by the Savannah Sparrow, viz., 
and heavy grasses such as Agropyron repens and Agrostis 
palustris. 

Spiza americana. Dicksissel. This, the last resident to arrive 
on the subdivision, was noted first May 29, 1926. The first songs 
were noted May 31, and from that time to the last of July its 
presence could not be overlooked. The maximum number of 
singing males was reached June 10. No definite effort was made 
to locate nests but the birds persisted in the taller, ranker growth 
of the area, especially wherever white sweet clover (Melilotus 
alba), the canada thistle (Cirsium arvense) and wild lettuce 
(Lactuca sp.) abounded. The Dicksissel will nest in meadows 


E 


Ecology of the Nesting-Site 121 


of clover, alfalfa or timothy but here they avoided the larger 
areas of blue grass, red-top grass, quack grass and timothy, 
restricting themselves to much coarser vegetation. This is in 
accord, too, with frequent observations I have made of them in 
eastern Nebraska, where scores of nests have been seen. Nine 
breeding pairs were shown by the June census, nearly all in 
such conditions as described. 

If, in a large area such as these subdivisions, where every pos- 


200 yards scale 


Legend: : 
“ep - Spotted Sandpiper 
U- Plover 
Olink 


Spo 

Upland 

B - Bobol 
Mu 


v 
M 
Figure 18 


r than the Prairie 

es eecaia tack eae bef tar in = 7 Risneee Ill. 1926, with 
the approximate location of the nests. 

sible habitat of the open field prevailed, the Dicksissel chooses 
the heaviest growth of large herbs, then such preference places 
him sixth in the ecological categories that vegetation erects: the 
Prairie Horned Lark in the scantiest growths, then the Vesper 
Sparrow, then the Meadowlark, then the Savannah Sparrow, 
then the Bobolink, and, lastly, the Dicksissel. 


122 Trans. Acad. Sci. of St. Louis 


Summary of all breeding birds of the region in June: 
Rentticn SANGDIDEr oc voce es bets aeus ie cere bettas 


RN PIOU OL ee os ia es oe ees vas eee bleep alee 1 
nie SEOPRON LATE occ. Gos key cas aad see bbe eee es 4 
PaO ee i ee ee eens deen 15 
PARI NPN rs a a Sc a ee ees Sk ee 18 
OY SAITO oe ees Gh os be caves eee hates 5 
POR SURTTOW oes Goes one sat eee eeeers overs 
SEPOREUODTOS SORCTOW: 655 46S sacked ee cescces 12 
ROE ce or a ei he Oe eRe eR OS SEs 
TOURT MEME PAE: oe ek ke pbs cea os ees eee 74 
Largest number In one block. ...006..5 os ee cece eee at 
Siiatiest number: in one block::. 0.0.5. chee ee s | 


NON-BREEDING BIRDS THAT FED ON OR ABOVE THE 
TERRITORY OCCUPIED BY THE PRAIRIE 
HORNED LARK AT EVANSTON, ILL. 


Though not so significant as breeding forms of the region still 
a final item of some interest is that which completes the remain- 
ing avifauna found in the vicinity of the home of the Prairie 
Horned Lark. The open field did not present a suitable breed- 
ing ground for these or was not in the proper latitude, yet on 
it or above it they appeared and because of this they have 4 
relationship to our main subject. : 

Grus mexicana. Sandhill Crane. Two alighted on the West 
Subdivision, May 2, probably attracted there by the ungathered 
corn. 

Phasianus torquatus. Ring-necked Pheasant. The Pheasant 
was heard crowing throughout the spring in the grassy marsh 
to the south and a pair was flushed from a weedy hazard in 
July, 1926. 

Zenaidura macroura carolinensis. Mourning dove. The Main 
Subdivision and that to the west were favorite feeding areas for 
the Dove. Here the bird was noted first July 4, 1925, again 
October 4 and 25, 1925. In 1926 the first was seen March 19, 
but none again until April 18. From this latter date until July 
22 (the last visit) they were noted daily, oceasionally two or 
three only, but again in flocks of ten to twenty. 

Love flights were frequent and songs occasional though the 
subdivisions were not breeding grounds but a mutual feeding 
place. On the Main Subdivision the Doves were always in the 
old sand hazards, very probably securing grit, but on the West 


Non-Breeding Birds 123 


Subdivision a small field of ungathered corn provided an endless 
resource of soft, rain-soaked and sprouting food. Here, in July, 
hundreds gathered, and a journey across the field would be 
accompanied by intermittent, sharp staccatos of wing whistlings 
as flock after flock arose. The Mourning Dove is not a common 
breeding bird in Northern Illinois, indeed, not a single nest was 
located in four years in the vicinity of Evanston. It is probable 
then that these birds, so numerous here, were coming from breed- 
ing grounds many miles away and from many diverse localities, 
to these unusually prolific feeding areas, since they appeared in 
small fiocks through the spring and summer. The fact that no 
young birds were noted, even in July, further enforces the view- 
point of their distant journeys. 

Circus hudsonius. Marsh Hawk. The subdivisions were hunt- 
ing grounds for the Marsh Hawks, but they did not breed there 
though possibly they did so in the weedy marsh to the south. 
This hawk was noted first on March 19, 1926, and regularly, 
though not daily, from that time until May 2. 

Falco sparverius sparverius. Sparrow Hawk. This little 
falcon nestled in a woodland northwest of the subdivisions and 
hunted over this area almost daily. Perhaps it may be held 
accountable for some of the destruction of nestling Larks. The 
hawk was seen November 25, 28, 1925, January 28, February 7 
and 28, 1926, and very frequently from that time on during my 
visits to the area. 

The adult Larks showed no fear of the Sparrow Hawk, but 
when once it alighted near a Lark nest the birds ceased feeding 
their young for a period of more than thirty minutes during 
its stay and complained vociferously the while. 

Asio flammeus. Short-eared Owl. Observed on the Main 
Subdivision, October 25, 1925. First observed in 1926 on April 
16, a day of considerable migration, apparently, for three were 
noted. One was flushed April 29, one again April 30, and the 
last noted was hunting over the area, about sundown, on June 28. 

It is probable that the short-eared Owl was no factor in the 
economy of the Lark, first because it did not breed near, appar- 
ently, and secondly because it was probably not eating b 
A few pellets examined (April 20) contained fish scales and fish 

mes only. 

Melanerpes erythrocephalus. Red-headed Woodpecker. The 


124 Trans. Acad. Sci. of St. Louis 


same neglected corn which proved such an attraction to Mourn- 
ing Doves on the West Subdivision was also the reason for the 
presence of Red-headed Woodpeckers there. Throughout July 
these birds were noted in twos and threes on the field. 

Colaptes auratus luteus. Northern Flicker. The Flicker 
found ants on the subdivisions and was a more or less constant 
member of the bird fauna there. Observed there October 4, 1925, 
on April 23, 1926, and more or less regularly until July 17, 1926. 

Chordeiles virginianus virginianus. Nighthawk. The first 
flew over the area on May 21, 1926, several on May 31, and no 
evening’s observation from that time until July 15, failed to note 

em. 

The marshes to the south, the stagnant water of the open, 
newly laid sewers of the subdivision, produced myriads of mos- 
quitoes. These, after the first of June, were the attractions for 
the Nighthawks. They caught mosquitoes by flying close to the 
weeds and grasses. 

After the Larks had closed their vesper recitative and the 
toads had begun to trill, the flickering white wing-bars of the 
Nighthawk were the only active bird elements in the evening 
dusk of the subdivision. 

Chaetura pelagica. Chimney Swift. Through June and July 
the Swifts found good hunting in the air, high above the sub- 
divisions. 

Tyrannus tyrannus. Kingbird. Though there was no suit- 
able nesting territory in the immediate vicinity, the King-birds 
frequently perched themselves upon a weed stem of the margins 
of the Lark territory. From one to three were noted frequently 
from June 5 to July 17, 1926. 

Otocoris alpestris alpestris. Horned Lark. ‘This northern 
relative of the Prairie Horned Lark may have occurred more 
frequently on the subdivisions than I have definite records for. 
During late February, in March and in April roving bands of 
Larks were noted long after the majority of O. a. praticola had 
established territories, and had mated. Most of these groups 
were too timid to allow approach sufficiently close for observa- 
tion. They may have been OQ. a. alpestris, or O. a. praticola 
migrating to more northerly homes, or young praticola still un- 
established and unmated. 

However, on April 9, 1926, a flock of ten to fifteen seemed 


Non-Breeding Birds 125 


decidedly larger than praticola and, though they would not 
allow close-approach (sentinels were posted while the majority 
fed) it is probable that these were O. a. alpestris. On April 24, 
1926, the presence of this subspecies was definitely settled for a 
flock very similar to the earlier (twelve to fifteen individuals) 
allowed a group of us to approach within thirty to fifty feet. 
From that distance there was no question. The birds were 
appreciably larger and darker than praticola and their yellow- 
ish markings about the head (throat, forehead, superciliary 
line), so pronounced that it gave their head a brownish-yellow 
tinge even at one-hundred feet, whereas the impression of 
praticola, especially of males, is that of a generally whitish head, 
the yellow never being apparent until one is extraordinarily 
close and with good binoculars. Furthermore, the black mark- 
ings of these birds seemed less pronounced than in praticola, 
probably through absence of contrasting white. When first we 
started toward them they remained for a moment quiet, but 
shortly were walking about and feeding on the heads of Setaria 
and Amaranthus, indifferent to our presence. 
our observation they passed near a brooding praticola; 

the male of the pair was on the sidewalk near, within twenty feet 
of the strangers. To them he paid not the slightest attention 
though an intruding praticola would have been ousted promptly 
and with vehemence. These Larks, of the same species so far 
as anatomy was concerned, were at that time and that place 
physiologically distinct. No kinship was recognized. 

It is of great interest to speculate by what means ancestral 
history and environment had so modified these two forms, so 
closely related. Here was one, at home in northern Illinois, 
with a physiological cycle that prompted full song and pairing 
in February, nesting in March, renesting in April and with 
young now in the nest at the very time that these, so close north- 
ern relatives, were still roaming over his breeding home, in 
flocks, with no note but a mild ‘‘pseet,”” a month yet from their 
Season of song, a thousand miles from their summer home. 

Corvus brachyrhynchos brachyrhynchos. Crow. On April 
16 the first crow was seen on the subdivisions, and records are 
frequent for the remainder of April, through May, June and 
July. Families were seen from June 20 on and these groups 
were frequently on the West Subdivision in July. What they 


126 Trans. Acad. Sci. of St. Louts 


found as food on the Main Subdivision is not known but the 
ungathered corn of the West Subdivision was, undoubtedly, the 
attraction there. 

Agelaius phoeniceus phoeniceus. Red-winged Blackbird. In 
the marshy land to the south of the subdivisions several Red- 
wings nested but their occurrence on the area occupied by the 
Lark was adventitious or for food. The first was noted there 
March 31, 1926, and a few other records occur during the 
spring. The ungathered corn of the West Subdivision proved 
the chief attraction and accounted for most of the recorded 

saits 


Quiscalus quiscula aeneus. Bronzed Crackle. The subdivi- 
sions had but little attraction for the Grackle. This bird was 
seen on the area May 23, June 26, 28 and 30, and but one or two 
individuals in each ease. 

Loxia curvirostra minor. Crossbill. In the fall of 1925 the 
sunflowers along the drainage canal near the subdivisions were 
the source of food for small flock of Crossbills. Here they re- 
mained from November 8 to November 28, 1925, and were, a few 
times, noted in one or two of the small sunflower patches of the 
Main Subdivision. 

Acanthis linaria linaria. Redpoll. In an area of evening 
primrose stalks and dead plants of white sweet clover two Red- 
polls were found December 22, 1925. They were the only birds 
upon the entire subdivision. In the same place four were see 
on January 12, 1926. 

Astragalinis tristis tristis. Goldfinch. Like the Crossbill, the 
Goldfinch fed also on the scattering sunflower patches of the 
Main Subdivision in the fall of 1925 and in mid-July, 1926, they 
went into ecstacies over ripe heads of goat’s beard (Tragopogon 
pratensis) on the West Subdivision. They were noted on every 
visit from October 4 to November 28, 1925; appeared on the 
Main Subdivision for the first time on June 2, 1926, and fre- 
quently from that time to late July. 

Spinus pinus pinus. Pine Siskin. On October 4 and 25, 1925, 
the Siskin was noted in large numbers on the sunflowers of the 
Main Subdivision. 

Calcarius lapponicus lapponicus. Lapland Longspur. Here 
was a bird of the same mind as the Prairie Horned Lark, fully 
at home on the almost denuded, uninviting surface of the sub- 


Non-Breeding Birds 127 


divisions in late winter and early spring. If the Longspur had 
bred here it, most probably, would have given the Lark a true 
ecological competitor in breeding territories. 

The clear ‘‘dear’’ or ‘‘cheer’’ of the Longspur was heard for 
the first time on the Main Subdivision on J anuary 12, 1926, on 
March 19 the bird appeared in large flocks; was noted again 
March 26, April 9, April 16, April 23 (the last a male in full 
breeding plumage). Again calls were heard April 28, and 
lastly, on April 30, throughout the entire morning as I sat in 
blind at a nest of the Prairie Horned Lark, large flocks wheeled 
back and forth above my head with their ‘‘chur-r-r-t, chur-r-r-t, 
chur-r-r-t, dear!’’ 

Zonotrichia leucophrys leucophrys. White-crowned Sparrow. 
One only noted. It was taken in the ground trap, May 10, 1926. 

Spizella monticola monticola. Tree-sparrow. The weed patches 
of the Main Subdivision attracted Tree Sparrows from October 
25 to November 28, 1925, and from February 7 to April 30, 1926. 
On April 20, two were taken in the ground trap. 

Melospiza melodia melodia. Song Sparrow. No Song Spar- 
rows bred on the subdivisions but individuals occasionally 
ventured on from neighboring areas. Thus they were noted more 
or less frequently from May 21 to July 17. 

Progne subis subis. Purple Martin. On April 23, 1926, the 
first appeared above the Main Subdivision. One again May 7 ; 
and from thence until late July they were feeding in the air 
above the area almost hourly. 

Hirundo erythrogastrar. Barn Swallow. Like the Purple 
Martin, the Barn Swallow found good hunting over the subdivi- 
sions. From April 27 to July 5, 1926 their merry voices were 
rarely wanting. On July 3, a family of them found an old shed 
there and for three days they flashed in and out gossiping the 
while in their excitement over the discovery. 

Riparia riparia. Bank Swallow. Noted over the Main Sub- 
division June 2, 4, 5 and 17, 1926. 

Stelgidopteryx serripennis. Rough-winged Swallow. The 
only definite identification of this species was on May 6, 1926, 
though some of the records credited to the preceding May have 
been of this species. 

Dendroica palmarum palmarum. Palm Warbler. Was noted 
in the weeds of the Main Subdivision October 4, 1925. 


SUMMARY 


This paper attempts to give the history of the Prairie Horned 
Lark as carefully and extensively as the literature, more than 
220 visits to occupied territory, 33 nests, and over two years of 
study at Evanston, Ill., and Ithaca, N. Y. would allow. Visits 
were made to Prairie Horned Lark territory every month in the 
year. Thirty nests were followed daily from their discovery 
until they ceased to be occupied. The paper deals with a single 
bird subspecies yet so manifold are the fields against which such 
a subject impinges that even an extensive paper will miss some 
elements altogether, treat but briefly of many others, and cover 
thoroughly but a very few. 

Summaries accompany most of the major sections of this 
treatise. Here will be considered only the more important points. 


I. Range. 

A. Extension of range. Henshaw erected the subspecies 
Otocoris alpestris praticola in 1884, splitting it from O. a. alpes- 
tris. Prior to this, records of a new form of Lark and new Lark 
breeding records were published from lower Ontario and New 
York. These were variously interpreted as a “paler form’’ or 
as southward extensions of O. a. alpestris. Following 1884 a 
consistent and progressive series of records demonstrated that 
the Prairie Horned Lark, coming up probably from Michigan 
through Ontario, invaded successively New York, Vermont, 

husetts, New Hampshire, Maine and Connecticut. From 
New York or Vermont it seems to have invaded Quebee much 
later; and lastly on the north, (probably from New England 
states) New Brunswick, Prince Edward Island, and Nova Scotia. 
Shortly after its entry into New York, the Lark appeared in 
western Pennsylvania, then farther east in that state, and south 
into Maryland and West Virginia. Less complete evidence 
seems to show that Indiana, Michigan, Ohio, probably northern 
Kentucky, and southern Missouri have been occupied by this 
Lark since white man has entered and altered those regions. 
The regular advance of the bird, always consistent with geo 
graphic conditions, is suggested as an irrefutable evidence that 


128 


Summary 129 


such an extension is bona fide. It is suggested that this exten- 
sion of range has resulted from changes which civilized man has 
made by deforestration and cultivation; thus creating perma- 
nent, or seasonally semi-barren, conditions which the Prairie 
Horned Lark required. 
B. Primitive range. It is noted that the dryer portions of the 
prairies of Illinois have probably long been occupied by this 
ark. The studies of Forbes and Gross seem to indicate that 
the Lark, though it probably breeds in Lower Austral, Upper 
Austral and Transition Zones, seems to prefer the Transition in 
that state. It is suggested that the prairies of northern Mis- 
souri, Iowa, Wisconsin, Minnesota, eastern portions of Kansas, 
Nebraska, North and South Dakota and southern Manitoba, 
probably formed the ancestral home of the subspecies. Nearly 
all of this vast region would have been suitable for two broods 
in March, April and early May, though the bird would have 
been foreed to the more barren regions as the grasses became 
vigorous in late May, June and July. That this Lark species 
is versatile in the matter of occupation of new territory seems 
to be further demonstrated by the observations of Gatke and 
Saunders in Europe with regard to 0. a. flava. 


II. Migration. 

A. General. Subspecies of the Horned Lark vary from 
Strictly sedentary forms to others which leave their breeding 
range entirely and for long periods, and therefore are quite 
highly migratory. The Prairie Horned Lark, in migratory 
habits, lies between these extremes. This bird breeds north to 
the southern edge of Canada, migrates south to South Carolina, 
Kentucky and Texas. From the northern part of this range it 
is absent during the month of December and part or all of 
January. Throughout the remainder of the breeding range some 
indivjduals will be always present. 

B. Migration of sexes and individuals. Insufficient data on 
this subject seem to indicate that resident adult males arrive 
first on the breeding ground, next resident adult females, next 
transient males and females and lastly vagrants and immature. 


III. The Lark in Autumn and in Winter. 


Flocking. Young Larks flock shortly after nest leaving. 
— the breeding ground has become untenable due to vegetation 


130 Trans. Acad. Sci. of St. Louis 


they seek other regions. Flocks grow larger through additions 
of adults in August and September and then smaller as migra- 
tion begins. In flight the flocks are comparatively compact but 
they spread widely when the birds alight to feed or pass the 
night. 

B. Habitats. Larks in autumn and winter occupy regions 
essentially like those in which they breed in March and April, 
viz., semi-barren or almost denuded conditions which may be 
natural or due to some seasonal condition of agriculture. 


C. Associates in fall and winter. The Lapland Longspurs and 
the Shore Larks (Otocoris alpestris alpestris) are the only other 
birds which occupy conditions like those in which the Prairie 
Horned Lark occurs in fall and winter. 


D. Food in fall, winter and early spring. Observations of the 
writer indicate that food during these seasons is very largely 
weed seed and waste grain. These are in essential accord with 
the more extensive investigations of MeAtee (1905). 

E. Call notes. Usually ‘‘p-seet’’ when on the ground; in flight 
usually ‘‘p-seet-it’’; when flushed ‘‘zu-weet’’, ‘‘sur-reet’’, ‘“zeet- 
eet-it’’ or ‘‘zeet-it-a-weet’’. 

F, Flights. Short flights: choppy undulation of three or four 
rapid, even strokes, interrupted by space of two wing beats when 
wings are closed; note uttered on the climb of the undulation. 
Prolonged flights. one, two or three long strokes are made wit 
pause of about one wing beat between each stroke with wings 
folded ; then four to six rapid and successive strokes which cause 
a climb; note uttered on the climb. 


IV. Reproduction. 
A. Breeding Habitats. 

1. General. The literature shows a surprisingly large range 
of habitats in which the Prairie Horned Lark has been know? 
to nest. These habitats, resulting in the range of this Lark for 
the most part from agricultural activity or other human agencies, 
are those which most nearly result in barren conditions. Kt 
does not matter that these barrens may be seasonal or otherwise 
very temporary, if they are suitable for the initiation of nesting. 
That bare ground is the determinant is shown by the fact that 
Variations of moisture, soil, elevations and temperature will all 


Summary 131 


be tolerated, in the selection of nest sites. The Prairie Horned 
Lark does not differ greatly in the ecological condition of breed- 
ing habitats from other Horned Lark subspecies. 

2. The breeding territory at Evanston, Illinois. Some typical 
Chicago marsh, in the Evanston region, was drained for a golf 
course. The golf course was later cut up into real estate sub- 
divisions ; sewers were laid exposing a wide area of bare soil in 
the streetways; old sand hazards remained here and there. This 
Series of activities provided nesting sites for many Larks. More 
than a score of nests were located on this area (about 90 acres) 
in 1926. 

A plot of vegetable gardens, bordering the region noted above 
on the west (where Larks probably had nested for some years), 
was also subdivided and the vegetation subsequently neglected. 
Here several Larks also nested. 

The advent of vegetation in both areas and the demand of 
the Lark for bare ground, forced a seasonal succession of Horned 
Lark breeding sites first from lot surface, to streetway, to sand 
hazard, to vegetable garden, in the order that each was succes- 
Sively occupied by verdure. 

3. The breeding territory at Ithaca, New York. One nest was 
located on the overturned sod of a former hay meadow. Most 
of the observations were made on a tract of ground that was 
largely fall wheat, partly fall rye, and the remainder devoted to 
experimental vegetable gardens. The growth of the fall wheat 
forced the Larks from its surface by late May. The gardens, 
and portions of the fall rye area which were turned under as 
green manure, remained suitable throughout. Clean vegetable 
gardens will always present a considerable amount of bare soil 
and the Prairie Horned Lark is usually able to occupy them 
until late June. 

B. Song. 

1. Season of song. Extended, in the Evanston region, from 
mid-January until early July; in the Ithaca region, from mid- 
February to late June. 

2. Monthly variations in song numbers. Using flight songs 
for a criterion, it was found that May was the optimum month. 
The Lark sings, both from the ground and in the air, under all 
conditions of weather, though flight songs are most numerous On 


132 Trans. Acad. Sci. of St. Louis 


quiet, mild days; perhaps a little more numerous when the sky 
is overcast than when it is clear. 

3. Variations in song through a nesting period. Most vigorous 
period of song extended through nest building, egg laying and 
incubation. Perhaps of this period that portion of it when the 
female incubated allowed most song from the male since he 
attends the female carefully during nest building and egg lay- 
ing. Period of least song occurs when young are in the nest, 
for the male assists in feeding. 

4. Variations in song throughout a day. Ground songs are 
regularly distributed throughout the entire day; flight songs 
seem to be most numerous toward noon and near sundown. 

5. The relation of the song of the Lark to that of other birds. 
For three months the Prairie Horned Lark is the only singing 
bird in the open field; with the coming and establishment of 
other migrants in late May and June many other songs will be 
heard in that region. On June 16, 1926, the Horned Lark, the 
last to begin song, went into flight song at 4:00 A. M. The Lark, 
however, almost always closed the singing at night with a long 
period of recitative which in mid-June, would not close until 
after 8:00 P. M. 

6. Description of song. The literature contains several de- 
scriptions of the flight song of the Prairie Horned Lark, that 
of Langille (1892) seeming to be most accurate. He describes 
the flight. The song he describes as ‘‘quit, quit, quit, you silly 
rig and get away’’. This is the intermittent type; nowhere in 
the literature has a description of the recitative been found. 

7. Types of song. Songs are sung from the ground, from 4 

clod or any other slight elevation, the greatest elevation being 
the roof of a sample apartment put up on the Evanston area; 
and from the air. The ground gongs are similar to the flight 
songs though rarely as long or as systematically presented. 
: The urge to flight song may come at any time or after aD 
invading male Lark has been evicted from occupied territory. 
Larks will also go into flight song upon the approach of a human 
or they can be forced to go up by driving them for a time about 
their territory. 

‘The climb to flight song is distinctive and usually executed 
without a sound from the bird. The songs, in the air, are of 
two types: a recitative or rapid monotony of notes usually 


Summary 133 


uttered at the beginning of the flight song, though occasionally 
at other periods, never over a few seconds in duration, accom- 
panied by a steady beat of the wings; an intermittent uttered 
while the Lark sails, about two seconds in duration, followed 
by a somewhat longer silent period during which the Lark flut- 
ters up. The recitative can be transcribed as ‘‘pit-wit, wee-pit, 
pit-wee, wee-pit’’; the intermittent as ‘‘pit-wit, pit-wit, pittle 
wittle, little, little, leeeeee’’. Large rough circles are described 
overhead during the flight song or the bird heads into the wind 
if it is strong. The Lark closes flight song by a headlong drop 
to earth with wings tightly folded. 

Female Larks seem to. be unaware of the males in flight song 
though other males note the bird overhead. The territory which 
a bird may occupy in flight song is very extensive. Never were 
two visible birds noted in such a performance simultaneously. 
The one in the air is left undisturbed though his performance 
may carry him over many other Larks breeding grounds below. 
Breeding territories are not vertical for a distance above a few 
feet; the flight song territory is something quite different. 

8. Quantitative studies of song. 

a. Height of the Lark in flight song. Of several methods 
employed to determine the heights of Larks in flight song 
the most accurate was found to be the use of a binocular 
with an ocular scale. It was determined thus, through 
measurement of 25 songs, that the Lark sings from eleva- 
tions that vary from 270 to 810 feet. The average was 
464.4 feet. Differences in height seemed to be individual 
variations or due to weather. 

b. Duration of the flight song. Thirty timed flight songs 
varied from one minute to five; the average was 2.34 
minutes. 

¢. Number. of songs per minute during the flight. Inter- 
Mittents, regularly given, averaged 11.9 per minute. 

d. Relation of the singing male to the incubating female. 
An Evanston, Illinois, bird sang from song posts on the 
ground which, during one entire day, varied a few feet 
from the incubating female out to 100 yards. The average 
was 38.66 yards. Ithaca birds, with bigger territories, sang 
frequently as far as 150 yards from the nest. 


134 Trans. Acad. Sci. of St. Louts 


C. Nesting territories. 

1. At Evanston, Illinois. A breeding territory was delimited 
by a male Lark on February 7, 1926, at Evanston, Illinois. From 
his selected territory he could not be driven. This territory was 
about 100 yards square. Late March snows disrupted all terri- 
tories and it was not learned here whether the original sites were 
ultimately resumed or whether the same territory was main- 
tained through more than one nesting. The pressure of vege- 
tation in late May and June greatly modified the territories at 
Evanston and caused, eventually, the abandonment of most of 
those on the erstwhile golf course. 


2. At Ithaca, New York. A male Lark was forced to mark 
territory for the first time on March 13, 1927, though it had 
undoubtedly been established some time before this. Territories 
voluntarily marked were somewhat larger than those indicated 
when the birds were forcibly driven out. The regions of a breed- 
ing territory most frequently occupied were those boundaries 
which joined the territories of a neighboring Lark. 

The territories at Ithaca were much larger than those at 
Evanston. (Possibly due to fewer Larks attempting to occupy 
them.) At Evanston they were seldom over 100 yards square, 
at Ithaca they ran out to lengths of 300 yards, and widths of 
200 yards, in March and April. 

In general all suitable territory was occupied at Ithaca and 
most boundaries were established by the margins of unsuitable 
areas (see Figures 2, 3 and 4), though a large amount of suit- 
able territory, extending north of territory ‘‘C’’, was used only 
in part by this bird. 

Boundaries between males were often definitely established on 
ground that had no natural marker whatsoever. 


3. History of territories in subsequent nestings. The territory 
history of three pairs of Larks was followed from March to June 
at Ithaca. One influence only modified the territories, viz., the 
growth of vegetation. Territory ‘‘A’’, entirely on fall wheat, 
was abandoned completely by the close of the second nesting in 
May. Territory ‘‘B’’, in part on fall wheat and in part on the 
gardens, was gradually reduced to the gardens, from an area 
once 300 by 200 yards to an ultimate area about 100 by 50 yards. 
Territory ‘‘C’’, almost entirely on the gardens, suffered no major 


Summary 135 


reduction. But ‘‘C’’, whose territory abutted that of ‘‘B’’, gave 
no ground to the latter. 

4. Feeding in relation to nesting territories. Though most of 
the feeding was done on the nesting territories, a neutral feed- 
ing territory was discovered and others were indicated because, 
now and then, the Larks would go off on purposeful flights 
entirely out of their areas. 

5. The relation of the female to the nesting territory. The 
female would mark the same territory as that marked by the 
male and she, if anything, was more closely restricted to it than 
the male. She selected the nest site with little or no regard to 
the center of the area. 

D. Courtship. 

1. Fighting. Prior to the establishment of well-defined terri- 
tories, fighting between males is promiscuous; after that, fighting 
takes place only on territory boundaries, where two Lark areas 
juxtapose. The males, at the boundary line, frequently strut 
before each other and often peck the ground furiously, like 
barnyard cocks, but all fighting is in the air. On a boundary 
this fighting often results in a curious game of tit for tat as the 
male Larks chase each other back and forth. Every adventitious 
Lark, wandering into established territories, is promptly evicted 
by the male. Such a bird will leave without protest. So far as 
noted the female is never the direct cause of fighting, in fact 
fighting is most frequently noted when the female is brooding 
and the males are no longer attending her. Only once was a 
female noted to drive out another Lark, a male. She was defend- 
ing a recent nestling. 

2. Reactions of male and female to each other. The female 
has no courting maneuvers and was never observed to sing. 
Only once was she seen to importune sexual attention and then 
by a crouch and flutter similar to the actions of the female House 
Sparrow. The male struts frequently before the female with 
wings dropped, tail spread and horns up. He will assume this 
attitude before another male at the territory boundary 

Attention is drawn to the discrepancy between these shores 
tions of territory, possession of territory, fighting and signifi- 
cance of fighting, and those of many previous and some recent 
writers who have been inclined to give to the actions of these 

irds an unwarranted anthropomorphic significance. 


136 Trans. Acad. Sci. of St. Louis 


E. The nesting. 

1. Season of nesting. The literature contains four February 
records of nests and many records of March nests in many states, 
and two or three records of nests in July. The writer has records 
of nests from about March 21 to July 12, in 1926, at Evanston, 
Illinois; from about March 11 to June 28, 1927, at Ithaca, New 
York. 

2. Explanation of March nests. It is suggested that such a 
strange phenomenon as that of a Passerine bird nesting in March 
cannot be explained easily. The bird has too long a nesting 
season to explain it on the conditions that might exist in early 
spring alone; and then, in the range where the Prairie Horned 
Lark was studied, nests are frequently destroyed by inclement 
weather and many young die of starvation at this season. Since 
this bird demands barren conditions, and not verdure, for a nest 
site, the conditions are suitable very early and it is suggested 
the early-nesting physiological cycle may have been acquired in 
a more propitious climate and subsequently carried north and 
east. It is further noted that O. a. actia of —— nests in 
March where conditions are quite ideal. 

3. Weather control of March and April nests. With one excep- 
tion, all observed nests (a total of fourteen) of March and April 
were not begun until the mean temperature rose above 40 degrees 
Fahrenheit for two or more days in succession. The exception 
was the initiation of a nest on the first day that the temperature 
rose above a mean of 40 degrees Fahrenheit. Once weather con- 
ditions, suitable for the initiation of nesting activities, prevailed, 
no subsequent weather, no matter how severe, (excepting deep 
snow only) would inhibit these activities. Even birds that had 
nested in March and whose nests were destroyed by late March 
and early April snows, would not renest until weather condi- 
tions were as given, though this necessitated a delay of nearly 
three weeks in two cases at Ithaca, N. Y. That this was a delay 
eaused by the weather is easily demonstrated by the fact that 
an exceptional case (noted above) began renesting on a single 
suitable day, but two other Larks waited two weeks longer for 
renesting when weather again was suitable and for a longer 
period. (See Figure 8.) It is known that two of these birds, 
and probably all, had had former nests. 

On the basis of this known weather control it was possible to 


Summary 137 


calculate the frequency, over a period of years, with which nest- 
ings would occur in March, by a study of weather summaries for 
the month. The results showed one year when nesting was im- 
possible and sixteen years of possible nestings, at Evanston, III. 
(For. the years 1910 to 1927, inclusive, excepting 1924.) During 
ten of the sixteen years nestings could have been successful ; dur- 
ing two they would have been destroyed by snow; and duvie 
four, weather and snow would have made success problematical. 
At Ithaca (for the years 1916 to 1927 inclusive) the summaries 
showed one year when nests were impossible and eleven years of 
possible March nests. During five of the eleven years, nesting 
could have been successful; during four they would have been 
destroyed by snow; and during two their success would have 
been problematical. Summaries could not be obtained for years 
previous to the earliest here noted. On the basis of those obtained 
it is shown that northern Illinois has more favorable weather in 
March than Southern New York. New York, it is to be remem- 
bered, is a state recently occupied by the Lark. 

It is concluded that three or more inches of snow, lasting two 
or more days, would destroy a nest. 

4. On finding nests and the reaction of nest-building and egg- 
laying Lark. It is suggested that the discovery of nests during 
nest building is possible by locating first the calling or singing 
male. At this period the male will be attending the female 
closely and she will be discovered shortly. The status of nesting 
can always be determined by the actions of the female. During 
nest building she is very restless, runs here and there, flies up 
and away, but shortly returns. Eventually she may disclose the 
site of the nest excavation. These reactions are instinctive re- 
sponses to the desire for nest concealment. All nest building 
Seems to be done by the female. 

_ During egg laying the discovery of a nest is at best accidental. 
Neither male nor female has been noted to approach a nest 
during this period. They express no solicitude beyond that of 
nest concealment, which is a remarkable nonchalance, especially 
on the part of the female. This reaction is so marked that an 
observer can nearly always be assured of the status of nesting 
whenever it is noted. 

When incubation has begun the behavior is very different, as 
is also the behavior after the eggs have hatched. These reactions 


138 Trans. Acad. Sci. of St. Louis 


will be noted below. During these periods nests may be located 
by a systematic search that involves first, driving the male about 
until the female is noted (she will flush from the nest and the 
male will go to her), then a patient watch of the female will, 
after a variable length of time, disclose the nest. When young 
are being fed the male will, at times, disclose the nest much more 
quickly than the female, for he assists in feeding and has nest- 
concealing instincts that are very poorly developed. Though the 
nest of the Prairie Horned Lark is never concealed from above, 
it fits its semi-barren environment so closely that a promiscuous 
search over a breeding territory is nearly always tiresome and 
unavailing. An incubating or brooding Lark, as will be dis- 
eussed below, often remains close to her nest when the day is 
chilly or in the very early morning or toward evening. Nests 
ean be found under these cireumstances by a systematic search 
of likely habitats and so flushing the bird from the nest. 


5. Nest building. No evidence of the use of a natural depres- 
sion was noted either at Evanston or at Ithaca, all were dug by 
the female. According to Sutton (1927) and observations which 
the writer has made of O. a. strigata in western Oregon, this 
excavation is dug with both beak and feet. The nest is con- 
structed, usually, at the edge or partially under a grass tuft 
or clod which, in the case of the Prairie Horned Lark, lies most 
frequently on the west, northwest or north (see Tables 3, 4, 7 
and 8) possibly because the cold and violent winds, of the early 
nesting season, come from this region. The body of the nest 
consists of coarser stems and leaves with a finer lining within. 
The time spent in nest construction varies from two to four days. 


6. Seasonal variations in nest structure. The evidence shows 
that any seasonal variation in nest structure is due to variations 
in available material and has nothing to do with variations in 
*‘necessity’’ or ‘‘onerous duties’. 


7. ‘‘Paving’’. The majority of the nests of the Prairie Horned 
Lark showed a variable amount of clods, pebbles or similar items, 
Jaid about the margin usually on the side away from the protec- 
tive tuft or clod. These so-called ‘‘pavings’’, were, again, always 
composed of the material most easily obtained regardless of the 
permanency of such. It is suggested that the purpose of ‘‘pav- 
ings’, if there is a purpose, arises from the method of nest 


Summary 139 


construction and from the desire of the Larks to have a bare 
ground nest-approach. 

8. Eggs and egg-laying. The egg is described as having a 
background of grey with an occasional greenish tinge, which 
background is almost completely concealed with a fine speckling 
of cinnamon-brown. The cinnamon-brown often forms a denser 
ring about the larger end. Several other variations are noted. 
The average size was found to be 2.25 em. by 1.55 em. The eggs 
of natural second sets seemed to be a trifle larger than first sets 
of the same individual. The number of eggs per set varied from 
two to five; the average is about four; the smaller sets occurred 
early, the larger sets later. 

9. Incubation period. The optimum was determined to be 
eleven days. Only the female incubates. 

10. Reactions of female and male Larks during incubation 
period. The male shows little or no nest solicitude during the 
incubation period. The female has a highly developed series of 
automatic instincts of solicitude which are modified by time of 
day, condition of weather and frequency of disturbance. The 
most highly developed and probably the most recently acquired 
of these has been given the name ‘‘nest concealment by abandon- 
ment’’, or ‘‘casual abandonment’’. The female leaves the nest, 
in this reaction, when an intruder is at a long distance, and flies 
quietly away, low against the ground, and does not show other 
solicitude for a very considerable period. The distances of the 
intruder from the nest during this reaction vary from 25 to 100 
yards or often farther, a greater distance, it will be noted, than 
would disturb even a timid Lark under other circumstances. A 
reaction, that in many ways is the reverse of this, but still a 
marked exhibit of solicitude, is that called “distress simulation’”’. 
The ‘‘distress simulation’’ consists of a precipitate flushing and 
rapid flutter over the ground after the nest has been approached 
closely. This reaction would be given most frequently on very 
cold days, in the dusk of very early morning or evening and 
when the bird was flushed very shortly after a return to the nest. 
This reaction is certainly more primitive than the first here de- 
Scribed and is probably a culmination of the more frequent dis- 
traction display that most birds present when their nests are 
disturbed. Between ‘concealment by abandonment’? and ‘‘dis- 
tress simulation’’ a complete gradation occurred which, since the 


140 Trans. Acad. Sci. of St. Louis 


reactions are exact opposites in expression, involved a curve 
which dropped from the first to the zero point and then rapidly 
ascended to the expression of the latter. Thus between the two, 
lessened expressions of either reaction would result, with a cur- 
ious hiatus midway in which the incubating bird would allow 
an intruder to approach closely and then leave without an 
expression of either. Experimental flushing of an incubating 
bird from a blind showed that the bird, in one case, would give 
distress simulation if flushed in an interval that was less than 
two minutes from the time of her return; but would give casual 
abandonment if flushed after an interval of five minutes. (See 
Table 14.) A female Lark, shortly after being forced from a 
nest, would express her agitation by aimless ground pecking, 
and, to be sure, would eventually be driven by the incubation 
urge to return to the nest even though an intruder might be 
much nearer than the distance when the nest was originally 
abandoned. This complex of instincts involved both the urge 
to incubate, and the urge to protect. The instincts to protect, 
by whatever method, would all be overshadowed in time by the 
instinet to incubate. 

F, The young. 

1. Hatching. With the exception of those nests of early 
April, in which incubation began before the set was complete, 
all young hatched within an hour or two of each other. The 
young are fed within an hour or two following hatching. 

2. Feedings. In most cases the male assisted the female in 
feeding the young. In carefully observed cases he visited the 
nest less often, but brought greater burdens and fed more 
young at a visit than did the female, The total number of 
feedings during one day (April 30, 1926) was 117. An exten- 
sive summary is presented in Table 17. 

3. Food of nestlings. Observations of the adults and dissec- 
tion of a few nestlings showed that some vegetable matter 
(weed seeds) is fed in early spring, but that even in March 
most of the food is animal matter. Later in the season grass- 
hoppers become conspicuous in the diet. The adults dig UP 
both eutworms and earthworms. 

4. Reaction of adult Larks with young in the nest. The 
male shows solicitude for the nest and its contents for the first 
time after the hatching of the eggs. His solicitude is restricted 


Summary 141 


to calls. The female will leave her brooding in typical ‘“con- 
cealment by abandonment” when conditions are appropriate 
as when incubating; likewise she will go from the young in 
“distress simulation” under circumstances as noted above. Pro- 
portionately the number of “concealments by abandonment” 
decreases and “distress simulations” increase slightly. Other 
reactions, which are various primitive expressions of solici- 
tude, or intermediates of the above two, increase proportion- 
ately (see Tables 11 and 13). Perhaps the return of more 
primitive instincts indicates a sum total of greater solicitude. 
Since the female is frequently absent from the nest in food 
foraging, she will come in, as an intruder approaches, with 
calls and cries, 


One or two references in the literature show that the reac- 
tions to dogs is the same as to man, but hens were driven off 
by entirely different methods. 

5. Nest cleaning. The Larks removed all excreta throughout 
the full extent of nest occupancy. Much of the excreta was 
eaten by the adults early in the season and dropped to the 
ground fifty or more feet distant later. It is suggested that 
this seasonal change of habit may have been related to the 
available food supply. The instinct compelling excreta re- 
moval proved itself very strong, at times overcoming strong 
Solicitude for nestlings, and even fear. 

6. Developmental reactions of the young. The young showed 
a psychic development closely related to their rate of growth 
and not to their age. Young which were of the same age or 
but one day younger than their nest-mates often presented a 
psychic development two to four days behind them. This was 
due to uneven feeding which occurred frequently in the early 
Spring, because of uneven hatching or an inadequate food 
Supply. 

Normal nestings give a food response indiscriminately up to 
the fifth or sixth day. Just prior to this time their eyes open. 
Following this they respond not at all or momentarily only. 
They withdraw at a touch from the hand on the sixth day and 
Sink back quietly into the nest in “erouch-concealment” be- 
tween the seventh and ninth days. Upon being removed from 
the nest at this age they sit quietly upon any object upon which 


142 Trans. Acad. Sci. of St. Louis 


they are placed; prior to this time, they wriggle about when 
taken from the nest. They leave the nest on the tenth day 
and now they express fear by hopping and calling wildly 
when disturbed. An expression of this type of fear, prior to 
the tenth day, would take them from the nest prematurely. 

7. Growth of the young. Tables 18, 19, 20 and 21, together 
with Figures 12, 13, 14, 15, 16 and 17, give extensive statistics 
of growth of weight, length, length of tail and length of flight 
feathers. A lessening in weight growth occurs, normally, 
between the seventh and eighth days. This is brought about 
by the simultaneous unsheathing and drying of most of the 
feathers. On the other hand growth in length shows, if any- 
thing, an acceleration at this period due to the extension of 
the tail. Marked variations in growth occurred in the various 
broods measured and in the different young of the same brood. 
This was brought about by two things: the fact that a slight 
difference in age gave the older Larks a great advantage in 
securing food from the parents; and the fact that food was 
more plentiful later in the season than at the beginning. 

Weight growth curves show a gradual increase over the first 
three days, a very precipitate rise (except for April nestlings), 
for the next three or four days, a marked levelling during 
seventh and eighth (in one case the sixth), and a gradual rise 
during the ninth and tenth. Nestlings in May grew slightly 
more in the same period than a nestling in June and much 
more than a nestling in April. This decrepancy of growth 
seems closely (though perhaps indirectly) correlated with the 
temperatures of these seasons. 

Length growth curves show a precipitate rise during the 
first three days, a slight levelling during the next three days, 
and a precipitate rise during the sixth, seventh, eighth, ninth, 
and tenth days. The cause for the intermediate levelling is 
not understood, but the rise toward the end of the nesting 
period is brought about by the growth of the tail. 

8. Descriptions of the young at various ages. The recently 
hatched nestlings are rather heavily covered with down (a 
hecessary protection against sun and cold in their exposed 
location). The down is cream-buff in color. At nest-leaving 
age the young Lark is completely feathered, but presents an 
appearance quite unlike that of the adults; each feather of 


Summary 143 


the upper surface has a triangle of brown at its tip, the under 
surface is white except the throat, which is grey. 

9. Enemies. In the early breeding season the enemies of 
the young are weather and a scanty food supply. The weather 
may result in snows which bury them from sight. The scanty 
food supply may result in the starvation of one or more of the 
nestlings. Starvation results from the automatic feeding reac- 
tion of the adults wherein the nestling nearest that part of 
the nest which is habitually approached by the adults will 
receive the first feeding; if the food is scanty this bird will 
receive nearly or all of the food. Only when food is so abun- 
dant that the first nestlings fed do not swallow promptly will 
the remainder of the brood be fed. In this case food is with- 
drawn from the first mouths and put in the next and so on 
(as Herrick, in “Home Life of Birds” has shown). The female 
Lark rarely brings more than will go into one mouth; the male 
may feed two or more, but never four or five at a time. Those 
young Larks that have a few hours advantage in hatching (a 
full day in several cases in the early spring), will have the 
advantage in size that will allow them to push to that side of 
the nest over which the food always comes. They survive, 
the others may perish. Such occurred in many observed nest- 
ings in April. 

Predacious enemies cause a greater and greater loss as the 
season advances into June and July. The optimum season is 
shown to be May. 

10. The Cowbird and the Lark. One case of Cowbird para- 
Sitism was observed and followed. A Lark, which hatched 
before the Cowbird, came to maturity. The Cowbird probably 
did not. It is suggested that the early nesting season and 
the exposed habitat may mitigate against such parasitism as 
may also the early departure of the young Larks from the 
nest. However, the adult Lark will tolerate the parasitism, 
the food of June and July is suitable, so that other reasons 
prevent more extensive parasitism at this later season. 

11. Protection of the young. The young leave the nest, 
normally, on the tenth day, some three to four days before 
they can fly. Their protection during this interval is silence 
and a very effective “freeze” or “crouch-concealment.” Their 
plumage is remarkably adapted for this. The actions of the 


144 Trans. Acad. Sci. of St. Louis 


parents, especially the female, with her “abandonment conceal- 
ment” are calculated to take advantage of the protective color 
of nest and young at all ages. 

12. Nest leaving. Young leave the nest usually by following 
a parent that has brought food. One case was noted wherein 
the female enticed a belated nestling from the nest with a 
food morsel. The young fly in about five days after leaving 
the nest. They hop for some days after nest leaving whereas 
the adults walk. This hopping may be anatomical or an 
atavism. 

V. Molt. 


Dwight (1890) showed that juveniles and adults have a com- 
plete molt in late summer. Breeding plumage is acquired by 
the wearing off in late winter of the brown tips that obscure 
the areas of blac 


VI. Eeology of the Nesting Site of the Prairie Horned Lark 
in Relation to Other Breeding Birds at Evanston, III. 


Throughout March, April and most of May the Prairie 
Horned Lark is the only breeding bird in the open field. The 
growth of verdure at Evanston, Ill., presented such a range of 
conditions that nine species and about 74 pairs of birds were 
occupying it in June, however. Though most of the Larks had 
been driven from it by this change of conditions, a few re- 
mained in the barer areas. A category of these breeding birds, 
listing their nest sites in descending order from the heaviest 
vegetation to the scantiest, gave the following: Dicksissel, Bobo- 
link, Savannah Sparrow, Meadowlark, Vesper Sparrow, Prairie 
Horned Lark. The Vesper Sparrow, as well as the Prairie 
Horned Lark, suffered a seasonal modification of nest site and 
was obliged to move for later broods, about two weeks of plant 
growth behind the Lark. Comparisons of many other habits 
are also noted. 


VII. Non-breeding Birds That Fed on or Above the Territory 
Occupied by the Prairie Horned Lark at Evanston, Ill. 
Twenty-eight non-breeding species of birds were noted feeding 
on or above the Evanston territory. Of these the most interesting 
were the Lapland Longspurs that occupied it with Larks i 


Summary 145 


late winter and early spring; and the Shore Lark (0. a. alpes- 
tris) that was noted in April. To the Shore Lark the breeding 
Prairie Horned Lark was indifferent, indicating that this latter 
bird did not recognize the former as being of the same species. 


CONCLUSION. 


To one, who watched the Prairie Horned Lark on its home 
in the biting winds of January to the sultry sun of mid-July, 
no word fully expresses the deep impression made. To one, 
who has followed the vicissitudes of its life history through 
ever-changing seasons, interest in the bird becomes the more 
intriguing. Just a subspecies of a single species it is, but to 
one who would look deeply into its inner secrets, not even 
words in thousands express adequately the findings. 


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Prairie Horned Lark (Otocoris alpestris praticola) to the 
Eastern Coast,’’ Auk 21, 1904, 81. 

Townsend, C. W., and Allen, G. M. ‘‘Birds of Labrador,’’ Proe. 
Boston Soe. Nat. Hist. 33, 1907, 277-428 (Review only, seen 
in Auk 24, 1907, 451-452.) 

Townsend, C. W. ‘‘Courtship of Birds,’’ Auk 37, 1920, 390. 

‘‘A Breeding Station of the Horned Lark and Pipit on the 

Gaspe Peninsula,’’ Auk 40, 1923, 85-87. 

Widmann, 0. ‘‘A Preliminary Catalogue of the Birds of Mis- 
souri,’’ Trans. Acad. Sci. St. Louis, 1907, 17, 143. 

Williams, R. 8. ‘‘Upper Missouri River Birds,’’ Auk 5, 1888, 15. 

Wilson, A. ‘‘Am. Ornith.,’’ 1, 1808, 85-87. 

——‘‘Am. Ornith.,’’ 2, 1831, 218-221. 

Wilson, G. ‘‘Birds of Bowling Green, Ky.,’’ Auk 39, 1922, 237. 

Wood, N. A., and E. H. Frothingham. ‘‘Notes on the Birds of 
the Au Sable Valley, Mich.,’’ Auk 22, 1903, 49. 

Woodruff, E. G. ‘‘Notes from Northwestern Conn.,’’ Auk 22, 
1905, 420. 

—*‘Otocoris alpestris praticola Breeding Eudy, Shannon Co., 
Mo.,’’? Auk 25, 1908, 202. 


INDEX 


Bold-face numbers refer to text figures. 
Roman numerals refer to plates. 


Acanthis linaria linaria 126 
Acknowledgments 2 
Actitis macularia 115 
Agelaius phoeniceus p 126 
Ammodramus savannarum australis 120 
Asio flammeus 123 
Astragalinis tristis tristis . 126 
Bartramia longicauda 114-115 
Bibliography 146-153 
Bird, the 1 
Blackbird, Red-winged iio ae 
Bobolink 115-117 


oe activities 


s at Evanston 


59, 61, 63, 65 
113- 122, 144 
oe 


J une census of. 
summ 


mary 


habitats : 34-37, “130-131 
general 34-35, 130-131 
ae en 35-37, 131 
oe 37, 131 
Brooding, Lark = een 
periods 94-95 
Calcarius lap pomicus lap mee es. ccececceccccceneeceeeecrneecerenceeensneee 126-127 
Call notes 33, 130 
Chaetura pelagica a 
Chordeiles virginianus virginianus a ee 124 
Circus hudsonius ee 
Colaptes auratus luteus te 
Coloration, concealing, of nestling oti ema XxXIil 
of youn = Bee 2.8 8 3 
Conclusion ee ee 
Corvus brachyrhynchos breach yr hy Meh 0s cece nnn A2O-126 
Courtship __.55-58, 135 

Cowhtrd 55 
and the Lark 106-109, 143, XXXII 
growth, and June nestlings. 105, 106 
Crane, Sandhill a 
: 126 


ross) 


peccerernseeesoneneere 


~» 


Crow 


125-126 


Dendroica palmarum palmarum 


Dicksissel 


Dolichonyx oryzivorus 


Dove, Mourning, 


Keology of nesting-site in relation to other breeding birds— 


Eggs, and egg-laying 


113-122, 144 


and nestling loss. 


80-84, 139 
100 


Enemies 105-106, 143 
Excreta, reaction to 94-95 
Falco sparverius sparverius 123 
Feeding 93-96 
in relation to nesting territories 55, 135 
Feedings 93-96, 140 
interval between 94-95 
sex 94-95 
table 94-95 
Fighting 56, 135 
Flicker, Northern 124 
Flights 33-34, 120 
Flocking 29, 129-130 
Food, in fall, winter and early spring... peta Pe 
of nes tlings : 
Goldfinch a 
Grackle, Bronzed ree 
Growth np 
average, in weight and height 108 
ee comparative i07, “XXXI 
leapt 102, 104 
; 99, 101, 102, 
Weight 7 105, 106 


June nestlings and Cowbird... 


Grus mexicana - 122 
Habitats 29-30, — 
Hatching 9198, 10 
Hawk, Marsh 193 
Sparrow a 
Hirundo erythrogastra von 
- 3-5 
general s 


egageicesth period 84-88, 139 
y of male during. 
ue of male and female during.....86, 87, 88-91, 139-140 


Introduction 1-2 
Killdeer 115 
Kingbird 124 
Lark, Horned 124-125 
Prairie Horned 

associates in fall and winter 80-81, 130 
Brooding XXII 
eall notes 33, 130 
coloration, concealing XXXIII, XXXIV 
female, approaching nest see. ©. 419 5 2 
incubating — 93 
reaction, protect 90 
relation of peers tanks wo 48-49, 133 
relation to nesting teYPritOry..ccccmencnnnnnen 135 
Fighting 56, 135 
flight ts 33-34, 130 
29, 129-130 
food, in ae winter and early spring... 31-33, 130 
of nestlin ngs __.96-97 
95-105, 101, 103, 104, 106, 108, 109, XXX, XXXI 
habita 29-30, 130 

binpne in April me 4S 
in autumn and in winter 29- 34, 129-130 
male, at fendile 3 eee I 


day’ s activity, during incubating period... 92 
in care of sous “ es > bee 6.6 = * 
relation of singing to incubating female. “48-49, 133 

nightly quarters 31 

reactions, during incubation period...........88- 91, “139-140 
nest-protective, of incubating female. “a 90 


of adults with young in the nest 97, 140-141 
of nest: building, egg-laying Larks.....68-71, 137-138 
to each othe 56-58, 135 
to man, when eggs were in the nest.......-86, 87 
when young were in the nest.....---87, 88 
AEE ee a ee Ii, IV 
r 
Prairie Horned—Continued : 
Whiter, aetivities oo It, 1% 
isis : ae 
pongepar: Teplen oo 126-121 


Loxia curvirostra minor ae 


Martin, Purple 127 


Meadowlark 117-118 
Melanerpes erythrocephalus .......... 123-124 
Melospiza melodia melodia ees sf 
Migration 23-28, 129 
general 23-26, 129 
summary 26 
of sexes and individuals.......... 26-28, 129 
summary 28 
Molothrus ater ater 117 
Molt 113, 144 
Nest, building 71-73, 138, V, VI, VII 
aning 98, 141 
construction, and pavings 
leaving 112-113, 144 
structure, seasonal variation in 73-76, 138 
Nesting 58-113, 136-140 


58-60, 136 


season 
site, ecology, in relation to other breeding bir 
113-122, 144 


territories 50-55, 134-135 
49, 50, 134 
feeding in relation to 55, 135 
sets in subsequent nestings. 52-54, 134-135 
Ithae 50-52, 51, 53, 54, et: 
sum 
Nestings, hypothetical.1910.1917 ‘i 
1916-1927 67 
mortality tables 110, 111 
Nestlings XXIII-XXVIII, gar 
loss 
ri Meee "96.97, 140 
growth 99-105, 101, 104, 106, 108, 109 
Nest i 62-68, 136-137, [X-XVI 
ests, Sue 68-71, 137-138 
es of suecessive aan a ae 
June VII-XX 
locations ; 70, 72, 74 
Mareh VII-VIIiI 
and April, weather controls he gw 
explanations 6 79 ss 
materials 
May 


pavings a 


protection 72, 74 

sizes AD; 

weights 79, 81 
Nighthawk 


Non-breeding birds at Evanston 


122-127, 144-145 


Otocoris alpestris alpestris 
Owl, Short-earned 


124-125 
123 


Oxyechus vociferous vociferous 


is 


Passerculus sandwichensis savanna 


119-120 


Pavings 


75, 76-80, 83, 138-139, VI-VII 
1 


Phasianus torquatus a 
Pheasant, Ring-necked . 122 
Plover, Upland 114-115 
Poceeetes gramineus gramineus 118-119 
a 1-2 
Progne subis subis 127 
Quiscalus quiscula aeneus eee vl 
Range 5-23, 128-129 
; aes gee SSS ee rn ee eee 
District of Columbia ae 
extension 0 5-8, 128-129 
llinois 18-2 
SO a en ee 17-1 
Kentucky .. 20 
ine _. 9-10 
Maryland .............. ee 14 
Masanenitinetts 2 ae 
Mbelaippecna © isc ta 18 
RE a a ee, 
New Brunswick 1 
Brew Tami ee 9 
TW NO ee 8 
Nova Scotia oe eek 
SON ee Sa 
Ontario ee 
Pennsylvania 13-14 
primitive .... 21-23, 129 
Prince Edward Island ee il 
Quebee 2100 
Sf ete Onn RUE Dense ae anne rmee er er 8-9 
14-17 


West Virginia 
Wisconsin .. 


aeoennsenee 


Redpoll 126 
Reproduction 34-113, 130-144 
Riparia riparia 127 
Sandpiper, Spotted 115 
Siskin, Pine 126 
Son 38-49, 131-133 
descriptions 41-43, 132 
flight, duration 48, 133 
numbers, per minute 48, 133 
visibility of Lark in 47-48, 133 


numbers, monthly variations in 
0 


38-40, 131-132 
49 


sts 
quantitative studies 


46-47, 133 

relation, to that of other birds 40-41, 132 
season 38, 131 
summary 49 
types 43-46, 132-133 
variations in, through nesting period 40, 132 
throughout a day 40, a 

Sparrow, Grasshopper 

Savannah = 1] ee 


ong 
Sparrow—Continued : 
Tree 


Vesper 

White-crowned 
Spinus pinus pinus 1 
Spiza americana 120-121 
Spizella monticola monticola. 127 
Stelgidopteryx serripennis = 127 
Sturnella magna magna. 117-118 
Summary 128-145 
Swallow, Bank 127 

Barn 127 

Rough-winged 127 
Swift, Chimney 124 

49 


Territory of a male Prairie Herned Lark 


Territories 
Tracks 


52-55, 51, 68, 54 


Tyrannus tyrannus 


Warbler, Palm 


Woodpecker, Red-headed . 


Young 91-113, 140-144 


ung 
descriptions, at various ages 101-105, 142-143 
developmental reactions 98-99, 7 142 
enemies 105- 106, 143 
growth 99-109, 101, 103, 104, i 108, 142 
protection 9-112, 143 
Zenaidura macroura carolinensis 122-123 


Zonotrichia leucophyrs leucophrys 127 


Plate II. The Prairie Horned Lark, Male and Female. foe a 
: : sis ~ ae side view. a “ 


PLATE II 


Plate III. Winter Activities of the Prairie Horned Lark. 
Fig. 1. Winter home at Evanston, II. 
Fig. 2. Tracks in the snow. Note the walking gait and the 
marks of the long hind spur. 
Fig. 3. Tracks of a male Lark through deep snow to a February 
song post, 


PLATE III 


Plate IV. Winter aren: of Prairie Horned Lark (cont.), and the 
Lark Home in April. 


Fig. 1. Amaranthus and tracks of the Lark made while feeding 
on its seeds 


Fig. 2. At Evanston, Ill. This area of about 90 acres had been, 
two or three years previously, a marsh, was then drained for 
a golf course, and after the Chicago Elevated built into the 
region, was subdivided into urban real-estate streets and blocks. 
This, in 1926, provided nesting sites for twenty-one located nests 
of the Prairie Horne 


Plate V. Lark Home in April (cont.), and Nest Building 

Fig. 1. At Ithaca, N. Y. The last of the snow that destroyed the 
March nests of the Larks is still on the hills but renesting 
had begun (April 6). 


ig. 2. A newly dug excavation for a nest between two tufts of 
fall wheat. 


bss 
os 
e 
< 
aa 
Ay 


Plate VI. Nest Building—continued. 
Fig. 1. - nest nearly completed. Note the material thrown out 
king the excavation and Joes two items (pebbles) of “pav- 
g” Tk have been carried i 
Fig. 2. An excavation under a clod beset with dead tufts of 
timothy. Note the few items (clods) of “paving’’. 


PLATE VI 


Plate VII. Nest Building (cont.), and a March Nest. 

. 1. A nest (that of Fig. 2, Plate VI) a completed. An 
ldssive “paving” has been placed about the border of the 
nest away from the dead grass ania All of the material 
here shown was laid within twenty-four hours. 


Fig. 2. Nest (A,), surrounded om sas Has covered by snow 
as, Ye a 


from the lower edge, show that the havk returned to the nest 
during an interval of the writer’s absence. 


PLATE VII 


ig. 2 


Fr 


Plate VIII. March Nests—continued. 


u 
nest is partially beneath a clump of fall wheat on the west. A 
mall “paving” (pebbles) leads off to the north. 


Fig. 2. Nest destroyed by late Marchsnows at Evanston, IIL, 1926. 


—_ 
— 
—_— 
= 
[ea] 
inl 
=< 
J 
As 


Plate IX. April Nests. 
Fig. 1. Fall wheat habitat of nest Bo at Ithaca, N. Y. 


Fig, 2. Nest Bo, April 15, 1927. Note that one egg is peculiarly 
marked. A later nest of this bird had a similarly marked egs 
(see Plate XVIII, Fig. 2). 


PLATE IX 


Plate X. April Nests—continued. 
Fig. 1. The habitat of nest D, at Ithaca, N. Y., the overturned sod 
of a former meadow 
Fig. 2. Nest D, April 17, 1927. An overturned bit of sod with a 


tuft of dead grass is on the northwest, a “pavement” of clods ex- 
tends to the south. 


‘3 5 


Plate XI. April Nests—continued. 
Fig. 1. Nest No. 3 in the dead and sparse grass and weed stuff 
along the streetway in a real-estate subdivision at Evanston, Ill., 
April 23, 1926. 
Fig. 2. Nest No. 5 built in the streetway of a real-estate subdi- 
vision at Evanston, Ill., with bare ground extending off to the 


r er. P 
northwest. Note the elaborate “pavement” of clods bordering 
the open sides (April 22, 1926). 


XI 


a 
eH 
< 
a 
ia 


Plate XII. April Nests—continued. 


Fig. 1. The streetway habitat which, in a single subdivision of 
about 90 acres near Evanston, Ill., provided suitable conditions 
for fourteen located nests of the Prairie Horned Lark in 19 
The nest in this photograph is in the inner angle formed by the 
two boards in the lower right-hand corner. 


Fig. 2. Nest No. 7, April 22, 1926. A near view of oe nest lo- 
cated by the boards in the habitat photographed above. Note 
the clod “pavement” laid along the board on the Marrs 
margin of the nest. ead Agrostis palustris surrounds the nest, 
a higher tuft of which is on the northeast. New spears of this 
grass are appearing here and there 


PLATE XII 


’ 
y 


Plate XIII. April Nests—continued. 
Fig. 1. The habitat of nest No. 12 within a lot of the real-estate 
subdivision at Evanston, Ill., April 25, 1926. The nest location 
y be seen in the center foreground. The short, dead grass is 
blue grass (Poa pratensis). 
Fig. 2. The habitat of nest No. 9, April 17, 1926, in the streetway 
of the peepee at Evanston, III. The nest is in the outer 


PLATE XIII 


sitet 
ey CER, 
oe, 


Plate XIV, April Nests—continued. 
Fig. 1. Nest No. 9, April 17, 1926, in the outer edge of the street- 


tecting tuft of Agrostis palustris on the west. ew leaves of 
yarrow (Achillea millefolium) are appearing in the foreground. 
Fig. 2. Nest No. 11, April 22,1926, in bare, cracked soil thrown 


up by the laying of a sidewalk in the subdivision at Evan- 
ston, Ill, 


PLATE XIV 


Plate XV. April Nests (cont.) and an Early May Nest. 


Fig. 1. Nest No. 11 (see Plate XIV, Fig. 2), in near view. There 
is no protection near the nest—one of a very few exceptions to a 
general rule. 

Fig. 2. Nest No. 15, May 5, 1926, in a streetway of the Evanston, 
fll, subdivision. .A dead tuft of Agrostis palustris arches over 


PLATE XV 


Qh ms; 


* 


i 
Pe a 
a 


Plate XVI. A Late April Nest and a May Nest. 


Fies 2, st As, April 26, 1927, at Ithaca, N. Y. Fall wheat forms 
the Peo. on the north. This nest was built in the same 
territory as A, about eighty yards from the site of that earlier 
nest. One of the — here is unusually marked with black 
blotches at the larger e 


Fig. 2. Nest C between rows of fall rye at Ithaca, N. Y., May 3, 
1927. The nest protection, a heavy weed-root, is on the sonsiseat: 
the only case where the protection was not on the west, nor 
west or northeast. The eggs here have an unusually heavy ring 
of spotting about the larger end. 


PLATE XVI 


§. 


th. 


‘ 


cZINS” 


BAY 


J 


Plate XVII. May Nests (cont.) and a June Nest. 


Fig. 1. Nest No. 14, May 4, 1926, in the streetway in the Evan- 
ston, Ill., subdivision. One of the very few nests of the Prairie 


palustris, dead blades of which arch over the nest on the north. 
New leaves of this grass are coming through the old. 


Fig. 2. Nest No. 20, June 6, 1926, in the Evanston, IIl., subdivision. 
It contains two Cowbird and three Lark eggs, the only case of 


Cowbird parasitism in thirty-two observed nestings of the Prairie 
Horned Lark i . 


y rain, extends to the southeast (right-hand side) and a dan- 
delion plant (Tararacum officinale) arises on the south. 


lam 
S 
ei 
ra 
ea) 
< 
4 
Ay 


Le ot 


“a 


Plate XVIII. June Nests—continued. 


Fig. 1. Nest B; and habitat, June 9, 1927, at Ithaca, N. Y. The 
nest is in the center foreground. The tomato plants were set 
out after the nest was built 


Fig. 2. Nest Bs in near view, On the west are stems of rye that 
the plow failed to turn under. The protection consists of two 
clods on the northwest. Note one egg with peculiar markings, a 
condition that existed in a former nest of this individual (see 

Plate IX, Fig. 2). 


Ill 


ATE XV 


PL 


Plate XIX. June Nests—continued, 


Habitat of nest No, 21, June 27, 1926, in the Evanston, 
Ill., subdivision. The nest is in the center ground, between the 
foreground and the nearer sidewalk, 


Fig. 2. Nest No. 21, June 15, 1926. 


1 
clod “pavement” of this side has 
n obliterated by rain. 


PLATE XIX 


Plate XX. June and July Homes of the Prairie Horned Lark. 
Fig. 1. The Ithaca home in June. 


ground has forced the Larks to 
the foreground. 


The fall wheat of the center 
the cultivated garden areas of 


e few bare spots of this old vegetable garden west 


, Ill., here given over to real-estate subdivision and 
weed-beset, the Larks were forced for the last of their nests 
in 1926 (July 10), 


PLATE XX 


Plate XXI. A July Home and Nest of the Prairie Horned Lark. 


Fig. 1. Habitat of nest No. 22, July 10, 1926, in a deserted but 
subdivided vegetable garden at Pie Til. e dominating 
weed is charlock (Brassica arvense). Beside a clumb of this, in 
the center ground, the nest was placed. 


- 2. Nest No. 22, July 8, 1926. On all sides but the southeast 
coe lres (Brassica arvense) rises. When the nest was con- 
structed, some three weeks earlier, the habitat was undoubtedly 
less weed-grown, more in keeping with Lark requirements. 


PLATE XXI 


Plate XXII. The Brooding Lark. 


Fig. 1. Female brooding young of nest B,, March 28, 1927, at 
Ithaca, N. Y. 

Fig. 2. Female brooding young of nest No. 6, Evanston, Ill., April 
25, 1927. 


PLATE XXII 


Plate XXIII. Nestling Prairie fed tea Larks of Nest No. 7, Evanston, 
Ill. (see Plate XII, Figs. 1a 
Fig. 1. Two recently hatched young, two eggs, April 26, 1926. 


Fig. 2. Two young second day, two young first day, April 27, 1926. 


PLATE XXIII 


; 7 OLB }- 
Ie DP Bge 
ow ¢ — a4 a® 1G 
I JN Ap 
ies : i Te 


rele 
ve, 


* 


Plate XXIV. Nestling Prairie Horned Larks of Nest No. 7—continued. 
Dg fs 


Two young third day, two young second day, April 28, 
1926. 


Fig. 2. Young responding to whistle, April 28, 1926. 


PLATE XXIV 


Plate XXV. Nestling Prairie Horned Larks of Nest No. 7—continued. 
Fig. 1. Two young fourth day, two young third day, April 29, 
1926. 


Fig. 2. Two young fifth day, two young fourth day, April 30, 1926. 
The younger nestlings are now noticeably smaller and are forced 


the few exceptions to this position). 
7 


PLATE XXV 


Plate XXVI. Nestling Prairie Horned Larks of Nest No. 7—continued. 


Fig. 1. Young responding to whistle, May 1, 1926. All still re- 
spond, though the eyes of the older are opening, 


Fig. 2. Two young sixth day, two young fifth day, May 1, 1926. 
The discrepancy in size between the older and younger nestlings 
is here very noticeable, much more than the growth of one day 
(the difference in age), would account for if all had received the 
same amount of food, 


PLATE XXVI 


Fig. 2 


Plate XXVII. Nestling Prairie Horned Larks of Nest No. 7—continued. 
Two young seventh day, one sixth day, May 2, 1926. The 


p 
juvenile feathers of the seventh day birds are unsheathing. 


Fig. 2. Two young eighth day, one seventh, May 3, 1926. Almost 
t 


shed and the nestling changes ies in aspect. The seventh 
day bird is pushed deeper into the rear of the nest. 


PLATE XXVII 


AN 


Plate XXVIII. Nestling Prairie Horned Larks of Nest No. 7 (cont.) 
and the Female Prairie Horned Lark Approaching Her Nest. 
Fig. 1. Two young ninth day, May 4, 1926. Between this photo- 
graph and that of the preceding day the second of the two 
ounger birds died of Starvation, leaving two fully fledged 
nestlings shedding the last of their down 


Fig. 2. Female approaching nest B,, Ithaca, N. Y., March 29, 
1927, to brood young. The young are too chilled to respond at 


PLATE XXVIII 


Plate XXIX. The Male Prairie Horned Lark in Care of the Nestlings. 


Fig. 1. Male with excreta, on an old cabbage stump, by nest No. 
22, July 10, 1926, at Evanston, Ill 


Fig. 2. Male at nest C,, May 13, 1927, Ithaca, N. Y, 


* 


PLATE XXIX 


Plate XXX. Daily Growth of the Prairie Horned Lark During the 
Nestling Period (Photographs of the Same Individual, from 
N No. 1 


est 3, Evanston, Ill., except Fig 8, and Exactly One-half 

Natural Size). 
Fig.: 1: Hee, 
Fig. 2. First day. 
Fig. 3. Second day. 
Fig. 4. Third day. 
Fig. 5. Fourth day. 
Fig. 6. Fifth day. 
Fig. 7. Sixth day. 
Fig. 8. Seventh day. 
Fig. 9. Eighth day. 
Fig. 10. Ninth day. 
Fig. 11. Tenth day. 


PLATE XXX 


» 


Fig. 


1 


Fig. 


Fig. 10 


Fig. 9 


Plate XXXI. Growth of the Nestling Prairie Horned Lark (cont.) 
and a Recent Nestling. 


Fig. 1. Two young from the same nest (Cy, May 13, 1927, Ithaca, 
N. Y.) on the eighth day. The difference in their ages is a few 
hours only, but this difference is so vital in the matter of get- 
ting food from the parent that it frequently results in starvation 
of the younger. The smaller is retarded in size, feather growth 
and psychical ibaa Weight of larger 22.6 grams, of the 
smaller 11.5 gr 


g. 2. Young Prairie Horned Lark just after nest-leaving, July 
11, 1926 (nest No. 22, Evanston, IIl1.). 


PLATE XXXI 


Plate XXXII. The Cowbird and the Prairie Horned Lark of Nest No. 
20, Evanston, II. 


Fig. 1. Cowbird, first day, (left); Lark, second day, June 9, 1926. 


Fig. 2. Lark, third day, (left); Cowbird, second day, June 10, 
1926. 


Fig. 3. Lark, eighth day, (left); Cowbird, seventh day, June 15, 
1926. 


Fig. 4. Cowbird, ninth day, (left); Lark, tenth day, June 17, 1926. 
Fig. 5. Lark (left), and Cowbird in nest the day prior to nest- 


leaving, June 17, 1926. Note the advanced plumage of the 
Lark as compared with the Cowbird. 


PLATE XXXII 


, 
~ 
<r 


= here tl 
oe ee - ee 2 


Plate XXXIII. Concealing Coloration of Prairie Horned Lark Nest- 
lings. 


Fig. 1. The blending of natal down with nest surroundings (nest 
No. 13, May 7, 1926, Evanston, IIl.). 

Fig. 2. “Picture pattern” of light and dense shadows of the 
ground in the juvenile plumage of young near nest-leaving 
(nest No. 4, May 3, 1926, Evanston, II1.). 


— 
— 
i 
ps 
~ 
a 
ica) 
ES 
<< 
| 
Ay 


Plate XXXIV. Concealing Coloration of Young Prairie Horned Larks. 


Fig. 1. Recent nestling in ‘“crouch-concealment” in short, sparse 
grass. The young Larks are semi-precocial in that they leave 


oped a crouch-concealment, as have shore birds, and are always 
quiet when the adults are not near. 


Fig. 2. Recent nestlings in “crouch-concealment” on bare, cracked 
ound, 


PLATE XXXIV 


apers 


tions 
Pp. 
1 


bu 
10ns 

able 

Noy. 


ri 
ail 
isso 


* 


ont 


s of N 


of AY 
M 
r 


* 


al C 
“ransact 
Bods 

1 


. 


Cc 
PE 
of 


lo 


With 
Cat