148 EXPERIMENT STATION RECORD. 



76 per cent 5 times, and only 1 per cent 6 times. Tlie period between molts 

 was found under normal conditions to vary from 6 to 15 days, the first and 

 last stadia being somewhat more prolonged than the intermediary ones. 



" Specimens of Diapheromera, which molted 4 times, reached sexual ma- 

 turity on an average, in 50.06 days, while individuals which molted 5 times 

 required 57.56 days on an average, or an extra 6.6 days before beginning the 

 egg-laying period. It is evident thus, that those walking-sticks which molted 



4 times, omit the fifth molt and yet reach sexual maturity nearly a week 

 earlier than those specimens that pass through 5 molts. In all probability, 

 temperature plays an important role in the rate of development, but tempera- 

 ture alone does not explain why some walking-sticks molt 4 times and others 



5 times. We have repeatedly reared a number of Diapheromera which were 

 hatched on the same day, fed with the same kind of food and kept in the 

 same breeding cage throughout their entire life history under exactly the same 

 conditions of temperature, and yet some specimens molted 4 times while others 

 molted 5 times. Further experiments are necessary to determine a solution of 

 this i)roblem." 



It is said that the development of this walking-stick is often retarded by a 

 leaf-ovipositing tachinid fly {Phasniopliaga antennalis) and by an undeter- 

 mined host-oviiX)siting species. 



A bibliography of 103 titles is appended. 



Tlie effects of parasitic castration in Membracidae, I. Matausch (Jour. 

 N. Y. Ent. Soc, 19 {1911), No. 3, irp. 19J,-196, pi. i).— The author records the 

 finding of a large species of Telamona (near heliria) and Cm-ynota viera, as 

 well as Tlielia Mmactilata'^, infested with parasitic larvae. This association of 

 parasites with a malformation or inhibition of the development of the external 

 genitalia is said to occur also in Glossonotus, 3 parasitized specimens belonging 

 to this genus having been .received. That parasites produce the sexual anomaly 

 also in Cyrtolobus is shown by a specimen collected by the author at Woods 

 Hole, Mass., on July 13. Attempts to breed the parasites to adults failed. 



The California Christmas-berry tingis, C. Pemekrton {Jour. Econ. Ent., Jf 

 {1911), No. 3, pp. 339-343, figs. 18). — The tingitid species here considered 

 {Oorythuca arcuata) is said to be common on hawthorn in the eastern United 

 States and also on the apple and hawthorn in western Washington, where it is 

 probably an introduced insect. Its presence on the Christmas berry {Ilete- 

 romeles arhxitifolia) can easily be detected by the brown, sunburned appear- 

 ance of the under sides of the leaves. There are but few Christmas-berry 

 bushes in the Santa Clara Valley that escape the attack of this insect. It is 

 also found occasionally and sparingly on the live oak {Quercus agrifoUa) 

 where the trees ai'e close to Christmas-berry bushes. Much damage to this 

 bush results indirectly from the attack of this tingitid due to a black smut or 

 fungus {CapnocLium heteromeles), the spores of which readily growt in the 

 honeydew excreted in large quantities by the nymph. 



The nymph molts 5 times and gradually increases in size from 0.6 mm. to 

 2.6 mm. Under normal conditions in the Santa Clara Valley, the average life 

 cycle is passed in about 78 days. As its period of activity lasts about S months, 

 it seems very probable that there are but 3 broods a year. Where spraying 

 has been attempted, success has resulted from application of kerosene emulsion 

 to the foliage with underspray nozzles. 



American Psyllidae, HI, IV, D. L. Crawfoed {Pomona Col. Jour. Ent., 3 

 {1911), Nos. 1, pp. 422-453, figs. 4; 2, pp. 480-503, figs. -4).— A continuation of 

 the paper previously noted (E. S. K., 25, p. 53). Synopses are presented of the 



1 Jour. N. Y. Ent. Soc, 17 (1909), No. 4, p. 165. 



