12 
BULLETIN 535, U. S. DEPARTMENT OF AGRICULTURE. 
TABLE 3.—Life-history record of the horse-radish flea-beetle during 1916. 
| { 
Date 
Date : Egg and | Dateof |  Pre- Date of Total | 
eggs eee larval pupa- | pupal emer- pupal | Egg to 
laid. i stages. tion. period. | gence. period. | ; 
plant. 
Days. Days d Days Days. 
July 20 Bo UU ype 2 ae eee ee Died’ f= ieee e eeeee 
PRN Oe 53 27 Gi le sosee tel es ee Bh See 
21 53 27 6 | July 31 10 | 63 | 
24 56 27 3 31 7 63 | 
24 56 28 Ah ac cpane cea Bae ee Ae ete eee ee 
See el eee oe DIN Madore eS hae il Deo | cee ees Sau gle ee ee: 
July 27 59 31 4| Aug. 5 9 | 68 
27 59 31 4 Mi il | aD 
27 59 31 4 i il 70 
27 59 31 4 2 G | 66 | 
27 59 31 AN Died Se Saiee oe le a eee | 
27 59 31 4°) Wied ase Mosee se |oew a see 
EV SE eT (ete eat Ate es OHNE aAeaceana Oulky S| ee Sa! 63 
Sr ei hen sere DTA ee SL eee ee 63 
Ree UGS! [Sk ae aN SS Lis eye eee ere |e NU yet ee peepee 68 
Aug. 28 60 | Aug. 2 5 5 8 68 
28 60 2 5: eDiedaers|heeie see NE a ee 
28 60 3? Gre Died = 2 sake. eee eal en 
31 G3 jliietaaeee Fae ene L100 Aug. 5 6 68 
31 63 5 eo) 13 13 75 
31 63 5 5 13 13 75 
31 63 5 5 13 13 5 | 
31 63 5 5 13 13 (fay 
l}Aug. 2 65 7 Si DIGG Sets: | Ese aes a Sele ees 
May 29! 2 65 9 Fl SDIGGE Ea) |/Res oes alee meen 
2 stay Woe DS Cex Fame Laser sa ote) hw Ue el ee elle ae NS 
2 65 Died Sta aes Soe j---------- ee eee 
5 68 | Aug. 7 Dit Ted: Soe oe eae a ee ek ae 
5 68 A | DIOS Fae ee SR AES Dono 
5 G8 Diese] eB, 5c Re 9 | eg er ae 
5 G8a/EDicde aes ieeees eee [Sec os Sfate | aera ane emer ae ne 
5 682 |PDiedeyies Sis ees ee [EE ok pee SI le ees 
5 GOS yy oes ee al ee yee ve ee ll eect | ee 
Rely As 2 eg ee aS AEN Ou SE BE SD Ted eae es aes aa ee Te 
Aug. 7 70 13 | 6) Died ao ae ee eee 
vi CAN tne DL eto all a Sa ea (oa ee Ett ees Altes tele ae eran a ere 
9 72 | Died Vio 5 yamapi | SS Rat Set I pee at iil yen RO 
9 72) Died ees |e epee Lets ese ra | Leak CU Nsareae eee deae i 
9 72 | "Died 2. Hees We see Ea aS ee Ses ee en ee eee | 
9 (OA leet Di Lex0 ene ecru CEI Seelam = Cae 
BP aosee Nh Sons pueT edd of a beat SN 0 | ee ee MAC: CRT a TERR ae 70 
Aug. 13 75 | Aug. 20 | tig SDC tse ||-t 95355 | es Sees 
fon les 75 20 | i baal UD 12 Le a snc Sha cael Se 
13 75 20 iba MD Lec 2 | aes Sindee eee 
Sed Eg | Sef 1183p] (ER SSE ese b Ye DOAN ee Se 83 
WS Seeaces meas Soe | 13} eee | Died! od|Mes tee. See eee 
[esse ae ea eee seen tes Way se Deal es eae A205 Sen oes 83 
} aeons 5 (Re eer Se Nee DOSS Beene 83 
Nats Sea es] oe ew ne 4 0 Yi Feces tek ee ry Did | east ees 881 
1 Approximate. 
SUMMARY OF TABLE. ‘ 
Average:compinediege and larval stages's +. ca). ea 2 = 5 yen eee ts ee ee eat days. . 
AVerage prepupal period 30 Individuals. oe ee: ese ee do. 
Average total pupal period, 12 individuals. 2.4.42 eS ee eee do. 
Averageiege toradult; 20 individuals... 225) [ 02 ase a ee ee eee do. 
OTHER RECORDS. 
Appearance record: First observed on leaves of horse-radish just breaking through the ground at Green 
Bay, Wis., April 20, 1916. 
Copulation first observed May 2. 
RECENT INJURY. 
An account of recent injury by the horse-radish flea-beetle was 
received from a correspondent at Shermerville, Ill., who wrote Janu- 
ary 
specimens : 
I should like your advice on an insect which destroys my horse-radish. 
3, 1917, substantially as follows, and who, later, furnished 
It is 
causing thousands of dollars loss every year in this community, and there seems 
