237 



they are not protected by a good covering of web. Spiders occasionally 

 kill the adults, and damsel-flies and ladybirds [Adalia bipunctata, L.) 

 the larvae, but they produce little or no effect in the natural control 

 of the sawfly. 



Spraying experiments were carried out against A^. inconspiciia, 

 both with stomach poisons and contact insecticides. The former 

 were much more effective in killing the larvae ; Paris green, calcium 

 arsenate, magnesium arsenate and zinc arsenite caused considerable 

 scorching to the trees, but lead arsenate was quite satisfactory. In 

 dust form it was also effective, though it did not penetrate the webs 

 quite so well as the spray. 



The spray should be made of | lb. of the powder or 1 lb. of the 

 paste to 50 U.S. gals, of water, the dust of 1 lb. of the powder to 

 15 lb. of air-slaked lime or powdered sulphur. Both spray and 

 dust killed 100 per cent, of the pest. 



Severin (H. C). Eleventh Annual Report of the State Entomologist 

 of South Dakota for the Period ending 30th June 1920. — South 

 Dakota State Coll., Brookings, 1920, 40 pp., 5 figs. [Received 

 17th March 1921.] 



Inspection of nurseries in South Dakota has been thoroughly 

 carried out, and a list is given of the pests found, with their food- 

 plants. The importance of educating the public in economic ento- 

 mology and plant pathology is emphasised, and an account is given 

 of the lectures, etc., given and the publications issued to this end. 

 The research problems that have been dealt with are outlined. Data 

 concerning Neurotoma inconspiciia have been published [sec preceding 

 paper]. Gryllus assimilis, F. (common field-cricket), caused con- 

 siderable damage, especially to seeds and grain. Two egg-parasites 

 of it were discovered, namely, Ceratotclcia marlatti, Ashm., and a new 

 species of Paridris, of less importance. Remedial measures against 

 the crickets include ploughing or disking and harrowing in autumn 

 all fields that have shown injury and the edges of fields and roadsides, 

 in order to destroy the eggs, renovation of lucerne fields in autumn, 

 and the burning of piles of old hay or lucerne where crickets have 

 probably collected. When the crickets are abundant in fields, poison 

 bait should be used [R.A.E., A, v, 382]. Meromyza americana. 

 Fitch (wheat-stem maggot) has been studied. Two parasites, Micro- 

 hracon meromyzae , Gah., and Coelinidea nieromyzae, Forbes, were found 

 destroying the larvae, and the mite, Pediculoides ventricosus, is 

 predaceous on them. 



The pests of raspberries, blackberries and dewberries include 

 Oberea bimaculata, 01. (raspberry cane borer), of which the life-cycle 

 occupies two years. Eggs are laid in late June or July in the pith 

 of the cane, and the larvae, which hatch in two weeks, feed on the 

 pith and work downward. They pass the first winter in the canes, 

 and in the following spring work more rapidly, gnawing openings 

 at intervals through which the excrement is ejected. Usually before 

 the fruit matures the upper parts of the injured canes are killed. This 

 pest passes the second winter as a full-grown grub in the stem below 

 ground, and pupates in the following spring, the beetles appearing 

 in June and July. If the canes show signs of wilting at the tips in 

 July and are found to be girdled, the tips should be cut off two or three 

 inches below the girdle and burnt. Canes that are a year old and 

 are dying should be cut off close to the ground and burnt. 



