1921.] The Eighth Indian Science Congress. xci 
Provinces and often cause heavy loss to the cultivators, (ii) they are a 
frequent source of contamination of the cultivated rices through casual 
mixture and natural crossing. 
ieties commonly met with in the Central Provinces have 
been described and an eed t has been made to classify them in order 
to facilitate their recognition in the fields. Characteristic features of the 
wild rices are 0) ay they possess nee grains inside the Te (ii) 
wn 
not perfect ae ripe. 
Natural crossing has been found to take place in the wild rices * 
we tent of 7°9 per cent. Instances of Seay between plants with r 
green leaf-sheath have shown pre t the red colour of the leaf- sheath 
ices as a segregating character spliting in a Mendelian Beonortone 
of 3: 1 with Ps Green. Occasionally however, a ratio o 
Red : Gree s also been obta ar air such cases were inet few, ite 
3: 1 ratio Being by —_ ommon 
ices. The 
occurrence of certain wild forms mixed w many of the cultivated 
varieties suggests the Sony of prc sic fertilisation between the 
wild and the altigwtbd rice 
The problems sean with the use os es parasites 
in checking Insect Pests.—By M. A. 
e fasci vege | idea of the control of insect pests of plants ram, 
0 
urest, there are workers who doubt the efficacy of 
oes a eradioatin ing pests. 
e last few years the spotted bollworms of cotton have been 
experimented upon in the Punjab. 
ora asite to be effective it must have 2 much shorter life his- 
tory as Saaied to its host, it must lay a very large number of eggs; 
t . 
vely much damage, it is very important that it must be capable of 
‘« domestication ” so that it can be breed in an insectory under artificial 
conditions and distributed. 
erent in the Punjab.—By M. A. Husatn and D. 
Nata 
Itisu aitiy asserted thatin this country the time for resorting to 
operations like spraying has not yet come. The work in the Punjab has 
rc ved that the zamindars are anxious to take it up. Very successful 
spraying operations have been conducted 0 n a large scale against Citrus 
Psylla and Mango Rat pad = rices er fruit have gone up so much 
yeh oe hs spend m ney on co iioliag insect pests 
I essential to ene ide facilities red the fruit grower and means of 
doing so are suggested. 
