76 SCIENCE BULLETIN, No. 18. 



Enococcas coriaceus, Maskell (Figs. 55, 56, and 57). 



Trans. X. Zealand Institute, vol. xv, p. 229, pi. xv, figs. 1-3. 18!»2. 

 (Jurncy, Hi port ~th Meeting Aust. J.v.sw. Science, p. 273. 1898. 

 lM(),U,<,'att. Atjric. (razette X.S. Wales, vol. xi, p. 101. 1900. 



Tliits is the commonest species of this genus, and it is widely di,sti-il)uted 

 over Australia upon many different s])ecies of eucalyptus. There are many 

 variations in colour, but the general form is regular unless massed together. 

 Besides the regular host i)lant I liave once found it U])on a cultivated myrtle 

 at a ])lant nursery at Goulbiirn, NeM' South Wales. 



Kirk records it as doing a great deal of damage to i)lantations of young 

 blue gums {Eiicahi])t>(s globulus) iir New Zealand, into which country it 

 Avas accidentallv introduced sonu» years ago. We find it always more 

 vigorous upon all kinds of cultivated gums, in gardens and avenues, than 

 in the native bush, where it has many enemies among the ladybird beetles 

 and scale-eating nu)ths. 



Sac of adult female formed of a closely-felted papery secretion, egg-shaped 

 in form, attached on the under surface to the leaf or twig (a complete sac), 

 with a well-defined circular ojjcning at the apex on tlu' dorsal surface. The 

 colour variable from almost pure white to yellowish, buff, reddish, to a 

 bluish creamy tint. Length, iV of an inch. A\ hen massed together the 

 tapered oval or rounded egg-shaped form is often altered. 



Adult female fitting closely into the sac with the tip of the abdomen ex- 

 posed under the apical o])ening, broadly oval, showing abdominal segmen- 

 tation.' Colour dark red. giving off a rich reddish-brown stain when crushed, 

 when placed in caustic ])otash turning it to a bright carmine. In living 

 s]jecimens there are usually several white curled filaments i)rotruding from 

 the anal oldening. 



Antenna' seven-jointed -first, broad: second, thickened, longer: third 

 and fourth, longer than second: fifth and sixth, short, indistinct: seventh, 

 short. Legs, normal : tarsus, long ; digitules, fine hairs. Anal tubercles 

 standing out at tip of abdomen, dark coloured, stout, finger-shaj)ed, with 

 three stout spiny hairs on the oirter side, two on the inner margins, with 

 terminal set;c. Anal ring with eight flat haii's. Epidermis covered with 

 fine spines, short truncate rods and circidar orifices. 



My description is taken from a large series of living s])ecimens. Maskell's 

 descriiJtion is biief. and his figures somewhat misleading. 



299. Eriococrus ccriaccus. Cat. Coccid;e. p. 73. 



En'ococeus crojfi, n.sj). (Fig. 54). 

 The female ccxtcids thickly scattered over the bark of the young branchlets 

 of the Pej^permint Cum {Eiicalyptus piperita) growing at Salisbury C'Ourt, 

 iiear ITralla, New South Wales. The infestation by these scale insects 

 causes the bark to crack, flake, and become greasy-looking and blackened. 

 Half buried in these surface cracks, manv of the coccids form their sacs. 



