8 BULLETIN 889, U. S. DEPARTMENT OF AGRICULTURE. 
TasLE I1.—Length of egg stage of the clover stem-borer (Languria mozardi) in alfalfa at 
Tempe, Ariz. 
Eggs. 
Average 
Cage No. a Observer. eee _ Length | mean 
Date Num Date NTE | ofstage. | tempera- 
laid. ber. | hatched,}| ber. ture. 
1914. 1914. Days 278. 
| Rear se Oe ent Sa ee ING RKONe se Coe ae oceaaas June 25 June 28 74 
1912 1912 
Dae ee eee Wildermuth =-*---.2:: | July 30 1 ATS eat 1 2 84 
10 Sas Ses bases ae ao tees oReee re Serer | Aug. 6 1 | Aug. 8 1 2 89 
1916. 1916 
TRS (als ace ae eee WOW See tae June 14 2) June 1 2 5 82 
TWAS (ed eam eee Poe GO: es eae June 15 1} June 20 1 5 82 
DPISEa emer ce eee |e dents. Pee June 17 ee : : at 
A keV ea tee ee An ane AG Oba eee a sae June 22 1} June 25 1 3 79 
DQGSie ose. o5 2 See ease COM eee eee ee dower: 21 | en 02s 2 3 79 
ETS Ose cee sears | eae GOs ee ee eee dos 2) June 26 2 4 79 
IGS Teles rss rece eee OO Banas Soe June 23 ib e701 1 3 79 
Ube Biko eto eee neers ieee [ea GOS ee Aeasaeee June 24 1 | June 27 1 3 80 
Mar. 23 2 3 63 
ee ee ee ey Gabesaos eens Mar. 20 14 }}Mar. 25 2 5 59 
(Mar. 26 1 6 58 
TOQeS ese sae GOs ee PNG Apr. 8 1 6 62 
STG Q= Peewee eter ce emery |e ers Oe ee ree ee ee do... 1 Wee 9 1 8 62 
I 5) 2 3 60 
T100...-.....-----+--)----- do... ---+--+++--+-)--- do... aoe 6 1 4 61 
2 5 
DEA Opes ee ea do eee Mar. 15 7 {Mor OT a : Rts 
% fMar. 23 5 3 63 
4h 1405 wore eee ee ee eee = do coer ee eee ee ee ee ee Mar. 20 18 \ Mar. 25 2 5 59 
METS 7s cereal SA GOs eee July 11 9} July 14 5) 3 84 
FROGA OF AVE ee ects at ae ae nee ee cea 7 Bel eee eae 41 S/8a ene 
EGG. 
The eggs are deposited in the stem of the host plant, and in the 
case of alfalfa are deposited when the alfalfa has reached a stage of 
growth about 8 to 10 inches high. The adults always seem to prefer 
young, new-growing, and succulent alfalfa for oviposition. This 
apparently is contrary to observations made by Folsom and others 
that the females choose the older and more mature red-clover stems 
for oviposition. The eggs are deposited through a round opening in 
the stem made by the female and are always placed within a cavity 
made in the pith. 
The average length of the incubation period, as given in Table II, 
for 41 eggs is 3.8 days, with a minimum of 2 days and a maximum 
of 8 days. While the average time required for incubation is lower 
during periods of higher temperature, yet this variation is not always 
due to temperature conditions, for eggs under observation hatched 
in 3 days during the month of Agel. when the average mean tempera- 
ture was 60° F., while others during the month of June often required 
4 or 5 days for incubation when the temperature was 20° higher. 
It will be noted that these egg-stage lengths compare very favorably 
with the egg stage as reported by Folsom for Ilmois. He found the 
ege stage to be 5 days in length during May, while during July it was 
only 3 days. 
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