422 



Eeyne (A.). A Cocoonspinning Thrips. — Tijdschr. Entomologie, The 

 Hague, Ixiii, no. 1-2, 15th July 1920, pp.' 40-45, 1 plate. 

 Franklinothrips tenuicornis, Hood, which has been recorded from 

 Moro Island, Trinidad and Panama [R.A.E., A, iii, 566 ; vii, 185], also 

 occurs in Dutch Guiana. Its most peculiar habit is the spinning of 

 a cocoon before pupation. Reference is made to a similar observation 

 by Kurdjumov in the case of Aeolothrips fasciatus [R.A.E., A, iv, 166]. 



Insectenpoeder-produetie in Japan. [The Production of Insect 

 Powder in Japan.] — Teysmamiia, Batavia, xxxi, no. 2, 1920, p. 91. 



In 1910, p}T:ethrum was grown on 1,122 acres and produced 865,316 

 lb. of powder. By 1918 the acreage had risen to 10,474 and the amount 

 of powder to 6,720,000 lb. In 1919, these figures fell considerably, 

 being 3,809 acres and 2,479,680 lb. This reduction is due to cultivators 

 having turned their attention to peppermint and grasses suitable for 

 strawplaiting. 



Byars (L. p.). a Nematode Disease of Red Clover and Strawberry 

 in the Pacific North-west. — Phytopathology, Baltimore, x, no. 2, 

 February 1920, pp. 91-95, 2 plates. 

 During the summer of 1919 red clover {Trifolvum pratense) and 

 strawberry plants {Fragaria sp.) were greatly injured by a disease due 

 to the presence of a Nematode, Tylenclms dijjsaci, Kiihn (devastatrix) 

 [R.A.E., A, viii, 79]. The disease is only found in the Pacific North- 

 west and then only in the irrigated sections. Whether it is confined 

 to clover grown under irrigation has, however, not yet been decided 

 Apparently only those parts of the plant that are above groiuicl are 

 attacked. The Nematode is no doubt largely spread by water, and in 

 the case of strawberries it is probably disseminated by means of the 

 young infected plants used for propagating purposes. This Nematode 

 has also been found attacking a wild plant, Physalis sp. 



Rand (F. V.) & Cash (L. C). Some Insect Relations of Bacillus 

 tracheiphilus, Erw. Sm. — Phytopathology, Baltimore, x, no. 3, 

 March 1920, pp. 133-140, 1 fig. 

 Experiments with Diabrotica vittata (striped cucumber beetle) and 

 D. duodecwipuncta (twelve-spotted cucumber beetle) in connection with 

 studies on insect transmission of bacterial wilt of cucurbits are des- 

 cribed. It is evident that the former beetles harbour the organism 

 internally when they enter the fields in the spring, and apparently 

 their only source of infection is the cucurbit crop of the precedmg 

 autunrn. Infection may take place from the mouth-parts or faeces 

 of the insects when these come in contact with fresh lesions on the 

 leaves, provided that the injury involves the vascular system. Beetles 

 of the genus Diabrotica are the only known carriers of the disease in 

 nature. 



HowiTT (J. E.). Some Observations made in inspecting for Leaf Roll 

 and Mosaic. — Phytopathology, Baltimore, x, no. 5, May 1920, p. 316. 

 In northern Ontario the mosaic disease of potatoes appears year after 

 year in infected stock and is evidently spread from diseased to healthy 

 plants. The chief transmitting agent is apparently the leaf -hopper, 

 Empoasca mali, Le Baron. 



