483 



Smyth (E. G.). Insects and Mottling Disease. — Jl. Dept. Agric. 

 Porto Rico, Rio Piedras, iii, no. 4, October 1919, pp. 83-116. 

 [Received Mth September 1920.] 



Failure of other ordinary means of dispersion of the cane mottling 

 disease has led to the beUef that insects may transmit it, and there 

 seemfe better reason to suspect sucking than chewing insects of doing 

 so. The only insect yet observed in the field that would satisfy all the 

 conditions is the yellow cane thrips {FranMiniella sp.). On the other 

 hand from a large number of experimental tests made in insect trans- 

 mission, successful inoculations resulted from only four different 

 species of sucking insect. These were the West Indian cane-fly 

 (Stenocranus saccharivorus), the cane-leaf scale {Pulvinaria iceryi), 

 the yellow cane aphis (Sipha flava) and a mealy-bug {Pseudococcus 

 calceolariae or P. sacchari). 



In view of the fact that the number of successful inoculations was 

 very small, compared with the large number of tests made under 

 apparently favourable conditions, the question of insect transmission 

 cannot be regarded as settled. Other factors may have escaped 

 notice. 



It is possible that inoculation requires that the plant be in a condition 

 of rapid growth — a condition that does not occur in the potted test 

 plants. The possibility of the infective principle being carried by the 

 insect for a length of time, and undergoing a cycHc change in its body, 

 or of its being transmitted to the young through the egg before it 

 becomes pathogenic, has yet to be investigated. 



A bibhography of insect-borne diseases of plants is appended to 

 this paper. 



Smyth (E. G.). An Annotated Bibliography of Porto Rican Cane 

 Insects.— J/. Dept. Agric, Porto Rico, Rio Piedras, iii, no. 4, 

 October 1919, pp. 117-134. [Received 14th September 1920.] 



This bibhography includes 136 works pubHshed between 1880 and 

 1919, with an indication of the scope of each. 



Smyth (E. G.). List of the Insect and Mite Pests of Sugar Cane in Porto 

 Rico. — Jl. Dept. Agric, Porto Rico, Rio Piedras, iii, no. 4, October 

 1919, pp. 135-150. [Received 14th September 1920.] 



This hst includes all the insects and mites that have been commonly 

 found feeding on sugar-cane {Saccharum officinarum), with particulars, 

 in tabular form, of the common name, damage, distribution, food- 

 plants, enemies, and control of each. 



Smyth (E. G.). Nuestro Amigo el Anolis. [Our Friend Anolis.'] 

 — Rev. Agric. Puerto Rico, San Juan, iv, no. 5, 31st May 1920, 

 pp. 11-21. 



Over 75 per cent, of the hzards of Porto Rico belong to the genus 

 Anolis, and they are very numerous and ubiquitous, some hundred 

 or so being found to the acre of average land. Corresponding to this 

 abundance of lizards is the obvious scarcity of insect life compared 

 ■with conditions on the mainland. It is estimated that from 30,000 



(717) B2 



