148 
PSYCHE 
[Decemlier 
change in color. The periods are, of course, but appro.ximately correct, and are 
probably worthless. It has been indicated, from time to time, that the period of 
incubation in Trichoc/ramma is always several hours longer than tliat of the host, 
at any given date. By comparing the records for the periods of incubation of the 
latter as given by Quaintance and Brues (1905), page 52, and the table following, it 
is readily seen that this is not borne out by the facts. 
T.\BLF. OF THE EGG INST.\R.S ,\T DIFFERENT DATES, 1904. 
Date hatched. 
No. of 
observations 
Length 
instar. 
Date hatched. 
No. of 
observations. 
Length instar 
Average. 
Days. 
hrs. 
Days. 
hrs. 
May 30 
6 
3 
5 
Sept. 14 
50 
2 
9 
241 observa- 
31 
4 
2 
22 
24 
34 
2 
17 
tioas. 
June 7 
.30 
2 
22 
28 
9 
2 
12 
16 
14 
2 
16 
Oct. 1 
33 
3 
17 
71 hours, or 
17 
3 
2 
13 
5 
5 
3 
18 
2.95 days, 
24 
28 
2 
4 
17 
4 
3 
9 
average. 
25 
9 
2 
14 
19 
12 
4 
0 
No records, unfortunately, were made during April, July and August, and 
late October. 
BIBLIOGRAPHY. 
1883. Lintnek, Joseph Albert. On an egg-parasite of the currant saw fly — 
(Nematus ventricofnis). Psyche, Cambridge, Massachusetts, IV, 1883- 
1885, pp. 49-50. 
1885. Idem. On an egg-parasite of the currant saw-fly {Nemafus reniricosus). 
Second report on the injurious and other in.sects of the state of New York, 
Albany, pp. 218-219. 
1885. Riley, Charles Valentine. Fourth report of the U. S. entomological 
commission, being a revised edition of bulletin No. 3, cic. U. S. Dep. Agric., 
Washington, p. 103. 
1902. AIally, F. W. Report on the boll worm, Austin, Texas, ]i. 30. (Agric. and 
Mechanical College of Texas). 
1905. Quaintance, Altus I>acy and Charles Thomas Brues. The cotton 
bollworm. Bull. No. .50, U. S. Dep. Agric., Bureau Ent., Washington, p. 1 17. 
