236 



which coinpreheucl the distribution of the cieca, their various rehitions 

 to the bodies of the speeies possessinjn' them, and the kinds and nature 

 of the bacteria constantly harbored by them. Tlie discovery is one of 

 great interest and may become of impcu'tance. We liope that Prof. 

 Forbes will not contine himself to the Hemiptera in his investigations, 

 but will also follow the organs in other orders of insects which have been 

 similarly assumed to have pancreati<; functions such as the ramified 

 appendages of the stomacli in (hyllotalpa. 



Plutella cruciferarum iiiEnglaud. — The English Board of Agriculture 

 has j ust i)ublished a special report of the Intelligence Department, by Mr. 

 Charles Whitehead, on an attack of tlie Diamond-back Moth Caterpillar. 

 Mr. Wliitehead has given in this report a full account of the damage done 

 by this insect during 1891 in various districts in England, to which we 

 have already referred on page SI of Vol. iv. The author gives descrip- 

 tions of the different stages of the insect, an account of previous attacks 

 by the same species in Great Britain, a general review of its distribu- 

 tion, and some account of the presence of the species in foreign coun- 

 tries, in which, curiously enough, he makes no mention of its occur- 

 rence in Xew Zealand or the United States. Under tlie heading "Ex- 

 tent and nature of the injuries and losses to crops" a most deplorable 

 state of affairs is indicated, in some cases the loss on the Turnip and 

 Swede crop reaching 00 per cent. Tlie season seems to have been a 

 favorable one for the development of Tineiua of many species, and in 

 a number of cases the severity of the present season's attack by the 

 Plutella has been directly traced to carelessness in allowing the growth 

 of Wild Mustard, Charlock, Shepherd's Purse, and other Cruciferous 

 weeds in the vicinity of the fields the previous fall. 



The damage was mainly done in the vicinity of the seacoast, where 

 wild Cruciferous plants grow in great abundance. The dry weather, so 

 marked in the early part of the season of 1891, also aided in the rapid 

 development of the insect. A number of remedies were tried by farmers, 

 and Mr. Whitehead summarizes these in his general conclusions. A 

 mixture of soot in lime was shown to be the best remedy tried. Paraffin 

 (kerosene), quassia, and carbolic acid solutions are said to have been 

 " efficacious to some extent." Brushing off the caterpillars by means 

 of boughs fastened to horse hoes (cultivators) proved to be a good prac- 

 tice, especially where the hoes were followed by other hoes or " scuiiiers" 

 to bury or kill the caterpillars. Mr. Whitehead finally advises cutting 

 down the Cruciferous weeds in the spring, as they may serve as breeding 

 l)laces for the first brood of tlie insect, but he is of the opinion that the 

 unpropitious weather of the latter part of the season and the hosts of 

 parasites which have been developed Avill have reduced the insect to 

 such a point that next year will show but slight damage. Among natural 

 enemies Limneria gracilis and L. tibialis were noted. Of these L. gracilis 

 greatly predominated. 



