53 



describe each insect very briefly, with notes as to its geographical 

 distribution, the main facts of its life-history, the nature of the damage 

 done and the remedial measures which have been found to be of 

 service. What is especially valuable to economic entomologists, 

 is a list of references to papers dealing with each insect. The 396 

 illustrations, particularly those showing the damage done, are good 

 and well chosen. No less than 341 insects are dealt with and necessarily 

 the information on each is condensed. The chapter on insecticides 

 is brief and concentrated. The notes on control methods should 

 enable the fruit-grower to handle insecticides intelligently and with 

 success, and should help to deprive him of any excuse for not pro- 

 tecting his crops, so far as pests are concerned, by the latest and best 

 methods known to the Economic Entomologists of the United States. 



Del Guercio (G.). Le Tipule ed i Tafani nocivi nelle Risaie di Moli- 

 nella (Bologna). [Tipulids and Tabanids in the rice-fields of 

 Molinella (Bologna).] — Redia, Firenze, ix, (1913), pt. 2, 31st March 

 1914, pp. 299-345, 14 figs. [Received 12th November 1914.] 



Tipula oleracea, L., which is injurious in the rice-fields of Bologna, 

 appears about the middle of March, the males being first on the 

 wing. It has been stated that the eggs hatch in from 10 to 12 days, 

 but the time must be considerably longer, as no larvae were seen to 

 hatch within that period, either in the laboratory or in the open. The 

 larvae were most numerous in the meadows around the rice-fields, on 

 roads bordering on the latter, and on the grassy banks of ditches. The 

 larvae found in the rice-fields in spring are derived from the autumn 

 generation of adults. Experiments show that the larvae only live on 

 non-submerged ground, and the adult avoids water for the purpose 

 of oviposition. Tipulid larvae were found on the lucerne and clover 

 meadows which alternate with the rice- fields in the Molinella district. 

 The burrows are often in contact with the stems of the plants, making 

 it easy for the larvae to reach the leaves on which they feed. When 

 no more tender leaves are available, the older ones and not the roots 

 are attacked. In mid-September the earhest larvae pupate, either at 

 the bottom of the burrow or near the surface of the ground, the pupal 

 stage lasting seven or eight days. In 1912, the adults were on the 

 wing about mid-October, but in 1913, as early as the 5th September, 

 so that by the end of the month nearly all had oviposited, whereas in 

 the preceding year oviposition had taken place in mid-October. The 

 dates are important in respect of control measures before the winged 

 forms appear and oviposit. The eggs are laid in the clover and lucerne 

 fields lying among the rice-fields, so that the larvae which hatch out 

 in autumn occur in land intended for rice cultivation in the following 

 year. This land is ploughed up in autumn and the clods of turf harbour 

 the larvae until the end of March, when the work of rebanking, sowing 

 and flooding is begun. As a result the Tipulid larvae are found in 

 the rice-fields in April. While still dry and hard, the seed is not 

 attacked, but injury begins when the seeds are swollen with water and 

 begin to germinate, the small larvae sometimes completely eating them 

 out. Experimental proof was obtained in confirmation of the 

 fact that Tipulid larvae cannot survive under water. If the rice-field 

 is flooded to such a depth that breathing through the raised syphon 



