462 



The parasites reared from this weevil in Minnesota include the 

 Chalcids, Eiipelmus coleopterophagus, sp. n., Catolaccus perdubius, sp. n., 

 Uabrocytus ohscuripes. Ash., Polyneniu consobrinus, Gir., Eurytotna. sp., 

 and the Cecidomyid, Lestodiplosis sp. During July from 30 to 43 per 

 cent, of parasitism is recorded. 



A complete bibliography covering the period 1897-1915 and 

 including 42 works is given. 



RuGGLES (A. G.). The White-marked Tussock Moth. — Sixteenth Rept. 

 Minnesota State Entomologist for 1915 and 1916, St. Anthony Park, 

 1st December 1916, pp. 68-70, 1 fig. [Received 7th August 1917.] 



The past season has been favourable for the development of the 

 white- marked tussock moth [Hemerocampa leucostigtna] in Minnesota, 

 where basswoods, elms and maples are the principal trees attacked. 

 The life-history and control of this moth have already been dealt 

 with [see this Review, Ser. A, v, p. 174]. 



Marcovitch (S.). Insects attacking Weeds in Minnesota. — Sixteenth 

 Rept. Minnesota State Entomologist, 1915 and 1916, St. Anthony 

 Park, 1st December 1916, pp. 135-152, 4 plates. [Received 7th 

 August 1917.] 



The subject of weed-infesting insects is extremely complex, and it 

 is sometimes difl&cult to tell where the usefulness of an insect begins 

 and where it ends. Some insects feed entirely on one species of noxious 

 weed, and are thus entirely beneficial. Ceuthorrhynchus marginatus, 

 Payk., infests the seeds of the noxious dandelion {Taraxacum offici- 

 tiale), destroying about one-fourth of them. On the other hand, weeds 

 are alternate host-plants of some of the worst crop pests and often 

 foster serious insect outbreaks. The corn root aphis [Aphis maidi- 

 radicis] maintains itself on smartweed and foxtail until maize is 

 planted, and the tarnished plant bug [Lygus pratensis] has a wide 

 range of weed host-plants. The original habitat of native pests and 

 the places where they are most frequently found are the forest edges 

 and thickets, composed largely of rank weeds. With the destruction 

 of forests, and the building of roads, farm wood-lots, etc., the thicket 

 formation has greatly increased. The present paper only attempts 

 to deal with the insects infesting herbaceous weeds. 



Rumex crispus (curled dock) harbours Pegomyia bicolor, Wied. 

 (curled dock leaf -miner), the larvae of which were found in June 

 mining in the leaves. Pupation of one larva was observed on 15th Jime, 

 the adult emerging on 8th July. Gastroidea polygoni, L. (knotweed leaf- 

 beetle) oviposits in Polygonum convolvulus (wild buckwheat) at the 

 beginning of August on the underside of the leaves, which the young 

 larvae devour. Chenopodium album (lamb's quarters) is a host of 

 Pegomyia hyoscyami, Panz. (spinach leaf-miner). There are three 

 broods annually ; eggs are deposited under the leaves, the first larvae 

 being observed in May and June. Gnorimoschema artemisiella, Kearf. 

 (wormwood web-worm), is also found on this plant and on sunflower 

 and Artemisia, and on golden-rod as a leaf-miner. Larvae have been 

 observed in June, pupation follows in early July and emergence in 

 mid-July. Insects on Portuhca oleracea (purslane) include 



