CLOVER STEM-BORER AS AN ALFALFA PEST, 9 
LARVA. 
DURATION OF THE LARVAL STAGE. 
The duration of the larval stage is about 35 days under all condi- 
tions of temperature and moisture. Table IIT shows that 35 speci- 
mens averaged 34.5 days with a minimum of 24 days and a maximum 
of 54 days. This wide variation in time is due not so much to tem- 
perature as to an inclination of the larva to prolong the fourth instar, 
even after it is apparently full grown, previous to pupation, as at 
this time it rests for an indefinite period before the pupa is fully 
formed and the last larval skin is shed. 
TaBLe III.—Length of larval stage of the clover stem-borer (Languria mozardt) tn alfalfa 
at Tempe, Ariz. 
Date Date | Length | Average - 
Cage No. Observer. 7 eges larve | oflarval t eeu 
hatched. | pupated.| stage. pee 
ure. 
1912. _ 1912. Days. 2H: 
HOSS SER SES SENS R RSS SUAE See SBeroae Wildermuth.......... Aug. 8] Sept. 4 27 84 
1915. 1915. 
Bie SCR SIS ee EES EOS Caen (Cates ees eee eee ACO GhOh Maia 24 35 67 
IMO GS ieee Seek Sul onlig See yi ha Le Sarl es Ose Ss scones pr. 8| May 12 34 62 
MOOS Seep eeatlnme eh eaten aie A COARSaee ene Apr. 5| May 10 33 63 
FIMO OS (pss anaes bate tote aU NEI ee ze GOPE sone ere eres Apr. 9] May 3 24 64 
FIRS Q= ene near ager cy fetes Movers | cee CORA Bec ehas dante Apr. 5] May 15 40 64 
Hh TCO Oe area mec i a ee rae oe | a GO Saseisoee Asean ee CWssec COWsso5 40 64 
TTL OQS3 ate ae ohes ese ce cE eel Saeee GOR Gia ceeeeteeee Apr. 6] May 17 41 65 
1916. 1916 
PINS DSA ae alee eee ep lee eye Sem one te Waldermuth2< >= 222. June 22} July 23 31 85 
MMe OSS ieee ee tier aha eae ne eee Min Mer ON eet ee eee les do... do 31 85 
DDS TSE se oa ee ras a ee ici RE as OSes ee codsooecscalees donses PAE 2 41 86 
FINAL SOS Ota keene ate es a eee at eee ODER a See aes June 23 | Aug. 7 45 88 
TRAD S225 (ee eres pe tj a ee CORSE ee een lene GOnj sa AUS. 16 54 83 
MUDD SOS 3 Mase yee hs oe ee A ae oppocGlOse gS badcatadsaad|locs doz: = 0» 54 83 
MNBL SDS Asis seger ere ts Sheen ka eee aera Pe ee COMES Saas Soe See lace do.. July 28 36 82 
SUS IG = 1 See gens Sele een oe ca ee Scie hiare GIO3 Sas Sua June 24 | July 24 30 82 
FIRES 251 Qe ae ee eng eee en Sa Be rail eh cee GORE eke eleoe GOsee 5 | PAuesae4! 41 85 
HES OSS 2 eee een rtey See eine ae een ClO eas Meee EASA ees do. Aug. 7 44 85 
MIME SD 392 Bere ane ioc ps tes Ake ae tat AS ete So GOSS He aee eceere June 30] July 26 26 86 
AMES OSE Diet rete ee ate ora ey Be a al ae, 2 GOs ea eee July 16 | Aug. 16 31 83 
ETUC YRED Oe eager |e GO eee aac ta oe do.. Aug. 25 40 83 
EUS D3 =O [eee ne IE MP eos Sei om ELE GOR seo are eee [Bate do.. Aug. 19 34 83 
PIWSES D3 DS een ses oe hep pe a ae Era COR eis ae ae reoee nis done Aug. 14 29 83 
AS TESS SBT ae er ee de ectcal Bel COS See June 17 | Aug. 21 35 83 
BIH S 2329) etree eesti ce Nyce Te GOSSES Babee sone lean do.. Aug. 11 25 83 
MINE S23 aera me ape ete A eet Se Re ClO). ee ous eee eae doz: Aug. 25 39 78 
PIMPS 23= 3 8 teepetysre Settee ala a See vaifa a icrave GOs aaa eee ee ree do.. Aug. 21 35 83 
PINUS 23 Aline ema ose Maree hr ee ee GO a are June 18 | Aug. 14 27 83 
TSI =A eat ae oe et pn Fl pana Oo 4 SU ee al cic do. Aug. 18 31 83 
WIG D RTA pete aa es he ee aisles ee CIO) ae es pe SM lesa do. Aug. 12 25 80 
PISS S DSA Oia teat ara yeh eo 2 | Neiwieya COSA See tice ae tes do. do 25 80 
BIRLA O tp pte care cer pe ae ee PR Ch AGR Rese Se eae ae do. Aug. 26 39 82 
PBS DFE 5 Ries eens gee ee ee We alt oe 02 22 eee June 19} Aug. 16 28 83 
PIRES 23 Oe eerie eet oe eae oe acc ck oe cclecces CO Ko ait 5 ee el | eee dose. |) Auge. 2 33 82 
HPS 23-02 main Pee ies sac si. 2 eS occas 3|lscis = © dss eee eee | une 320): | -A ug. 24 35 82 
FAR CEA D Omert tie ee nape ere eS Sa chaps SNe he lade Sen Sle a Se: Se ee ee 34.512 s52eeceme 
The larve pass through four molts (see Table IV) and five instars. 
In experiments conducted by the authors and tabulated below only 
three larve were reared successfully from egg to pupa with a complete 
record of the number of molts and instars. This was due to the fact 
that the larve naturally feed within the alfalfa stem and can not be 
186607°—20——2 
