THE SUGAR-CANE LEAFHOPPER. jl 
~The Australian and Fijian material has been described in detailed 
reports with elaborate illustrations by Messrs. Perkins, Terry, and 
Kirkaldy.% 
Regarding the effectiveness of the various parasites and enemies of 
the leafhopper, Dr. Perkins says: ° 
lf we consider the effectiveness of the four egg-parasites, Paranagrus optabilis, P. 
perforator, Anagrus frequens, and Ootetrastichus beatus, in areas where all are well 
established, we must rate the first-named as at present by far the most effective. As I 
have previously pointed out, this species is capable by itself of destroying about 50 
per cent of the cane-hopper’s eggs and Anagrus frequens and P. perforator, extraordi- 
narily numerous as they appear, where seen alone, are but as isolated examples in 
the crowd, where all are well established in one spot. The Ootetrastichus slowly but 
steadily increases In numbers, and on many plantations I expect that it will ulti- 
mately be the most efficient of all parasites. I do not think that it can show its full 
value till 1908, for each harvesting of the cane crop is necessarily a very great setback 
to its natural increase. Anagrus frequens, under which name are probably more than 
one species, or at least one or two distinct races of a single species, although it appears 
at a disadvantage, when in company with Paranagrus optabilis, is nevertheless a 
most abundant parasite. In Part VI of this Bulletin I have compared the habits of 
the two and need not refer to the matter here, but I may say that as many as eighty 
or a hundred exit holes of the Anagrus have been counted in a single cane-leaf, so 
that its great utility is unquestionable. P. perforator, common in Fiji, attacking 
eges of hopper laid in thick stems of grass, more rarely those in cane, will probably 
gradually wander away from the cane-fields to attack the eggs of native hoppers, that 
are laid in stems and twigs, as it now chiefly attacks the cane-hopper eggs when these 
are laid in the stems. 
Nor must it be forgotten, what valuable aid these egg-parasites receive in the 
control of leaf-hopper from other insects parasitic and predaceous, native or introduced. 
In fact, had there existed previously no restraint to the multiplication of the pest, no 
a Wawaiian Sugar Planters’ Exp. Sta., Div. Ent.: 
Perkins, R. C. L.—Bul. 1, Pt. I, pp. 1-69, May, 1905 (Dryinide). 
Perkins, R.C.L.—Bul.1, Pt. I, pp. 71-85, figs. 1-3, June, 1905 (Lepidoptera). 
Perkins, R. C. L.— Bul. 1, Pt. II, pp. 86-111, pls. 1-4, August, 1905 (Stylo- 
pidee). 
PrEerxins, R. C. L.—Bul. 1, Pt. IV, pp. 113-157, nike 5 ie FNC s 1905 
Gonenia.) 
Terry, F. W.—Bul. 1, Pt. V, pp. 177-179, November, 1905 (Syrphidz). 
_ Perxins, R. ©. L:—Bul: 1, Pt. VI, pp: 183-205, pls: 11-13, November, 1905 
(Mymaride, Platygasteride). 
PERKINS, R. C. L.— Bul. 1, Pt. VIII, pp. 239-267, pls. 18-20; January, 1906 
(Hymenoptera). 
Kirxaupy, G. W.—Bul. 1, Pt. IX, pp. 269-479, pls. 21-32, February, 1906 
(Leafhopper). 
Perkins, R. C. L.—Bul.1, Pt. X, pp. 481-499, pls. 33-38, March, 1906 (Hy- 
menoptera, Diptera). 
Kirkatby, G. W.—Bul. 3, pp. 1-186, pls. 1-20, September, 1907 (Leafhop- 
pers, Supplement). 
Perkins, R. C. L.—Bul. 4, pp. 1-59, May, 1907 (Parasites of Leafhoppers). 
6 Perkins, R. C. L.—Leaf-hoppers and their natural enemies. <Hawaiian Sugar 
Planters’ Exp. Sta., Div. Ent., Bul. 1, introduction, pp. xv-xvu, May, 1906. 
