54 EXPERIMENT STATION EECORD. 



to the farmer and fruit jn'owcr. The closiiij; cluiptcr is devoted to a discussion 

 of the war on iuseets. 



The role of air in the ecdysis of insects, F. Knab {Proc. But. Sac. Wash., 

 11 (I'.Hi!)). -No. .?, 1)11. (jS7,i). — A brief consideration of this subject. 



Contribution to the biology of the Aphididse, A. Mokdwilko {Biol.. Centb!., 

 21 (I'JOl), A OS. 11, piK 520-550; 18, pi>. 561-575; 23, pp. 77/7-767; 2'/, pp. 769- 

 816. figs. 22; 28 (1908), Xos. 19, pp. 631-639; 20, pp. 6.'i9-662; 29, (1909), Nos. 

 3, pp. 82-96, figs. 2; J,, pp. 97-118; 5, pp. L'i7-160; 6, pp. 16 J/ -182). —The biology 

 of the plant lice is here considered at length. 



Contributions to experimental entomology, AV. Kkifk (Jour. Expt. ZooL. 

 6 (1909), \o. .}, pp. 553-569). — The experiments which the author here reports 

 were with Junonia ccenia, collected on Long Island. 



In regard to the period of pupation at different temperatures for caterpillars 

 reared at out-of-door temperature, he reports as follows : " The time of pupa- 

 tion, that is, the time which elapses between the attachment of the caterpillar 

 and the complete pupa, differs according to the prevailing temperature. At 23° 

 C. pupation took place in from 10 to 12 hours; 18° caused the catei-pillars to 

 pupate in IT hours; 9° in about 48 hours; 0° in GO hours, and below +4° pupa- 

 tion did not take place at all. The caterpillars, which I subjected for a long 

 time (up to S days) uninterruptedly to a low-er temperature, varying between 

 and +3°, died, no matter in what stage they happened to be." 



From the experiments conducted the author concludes that this species never 

 passes the winter in the northern States as a caterpillar and that all caterpil- 

 lars die as soon as the temperature siuks to -f3° for several daj-s. The pupa 

 is not quite so sensitive to continued cold as the caterpillar, but still is sensi- 

 tive to a considerable degree. All of the pupje which were exposed to a con- 

 stant low^ temperature ( — 5° or below) for more than 48 hours, died. "All the 

 pupfe which I exposed to a temperature of 45° for more than 2 hours, or such 

 as were exposed to 44° for more than 5 hours, died. Of all the pupse which re- 

 mained in the apparatus 5 hours at 43°, only one later produced a butterfly, 

 but this was a complete cripple. All the pupse endured very well for several 

 hours a temperature of from 40 to 42°. My method was to expose the pupje on 

 the first day to a temperature of 40° for 4 hours, the second day to 41° for 5 

 hours, and on the third day to 42° for 4 hours." The coloration and marlving 

 of butterflies bred from pupte which had been exposed to low temperature were 

 in complete contrast to those not thus exposed. The author considers this 

 species as probably in the act of adapting itself to cold. 



Notes on microlepidoptera, with descriptions of new North American 

 species, A. BuscK (Proc. Ent. Soc. Wash., 11 (1909), Xo. 2, pp. 87-103).— Sev- 

 eral biological notes are included in this account. 



Anacaiitpsis crcsccntifascidla is said to have been bred from Kramcria se- 

 cundiflora at Dallas and Victoria, Tex. Oletlircutcs alhicUiana w^as bred from 

 the stalks of touch-me-not (Impatiens) collected at Magnolia, Mass. "The 

 larva lives in the hollow stalk and in the succulent pith in the swelled joints; 

 it overwinters as larva and toward spring gnaws a small circular hole in the 

 stalk near a joint, leaving only the extreme epidermis intact as a semitrans- 

 parent port hole; just inside this it spins a few threads of silk and pupates 

 with its head toward the window, through which eventually the imago issues. 

 In the insectary the first moth issued the latter part of April." 



The lar\a of Tisficria alhostrauiinca makes a small, pale straw-colored ui)per 

 mine in the leaves of oak about Washington, D. C. The mine is normally 

 placed at the edge of the leaf, frequently causing the edge of the leaf to bend 

 over in a small fold. The species has several generations in the vicinity of 

 Washington. 



