808 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 
The jilcfet are Bhort and lingular; there are two with distal extremities fringed 
between tin- median lobes: two similar to these between tirst and second lobe of each 
ride; the lateral nember of this pair of plates is much wider than the mesal one; 
between the Second and third lobes arc usually four plates, each with its lateral mar- 
gin fringed ; between the third lobe and the lobe on the lateral margin of the seg- 
ment arc four or live plates similar in form to those between the second and third 
lobes; two of these plates are usually very small. The segment is narrowed caudad 
by a succession of notches. 
151. The Norfolk-Island-Pink Coccus. 
Rhizococcu8 araucaria (Maskell).* 
(Plate xxix, Figs. 1, la—lg). 
"The genus Rhizococcus was erected by Signoret to receive an insect 
(R. (jnidii) which he found on the roots of Daphne gnidium, and which 
differs, according to his description, from the species of Erioooceu* in 
no important anatomical character, except in the antennae of the female 
being 7-jointed. The specimens (female only) which Signoret studied 
were naked ; but he had not sufficient material to ascertain if the 
insect makes a sac or not in its most advanced stage. 
" During the past year I have studied two bark-lice which agree with 
the characters given for Eriococcus, except that the females have 7- 
jointed antennae, and remained naked until they are fully grown. These 
species I place provisionally in the genus Rhizococcus, and submit the 
following characters, drawn from the species described here, for that 
genus. 
Antenna? of larva and of the adult female 7-jointed ; ano-genital ring with eight 
hairs; tarsi of both male and female each with four digitales; margin of body of 
young and of female in all stages fringed with tubular spinnerets, which are covered 
with a waxy excretion ; adult male with single ocellus behind each eye, and a pair 
of bristles on each side of penultimate abdominal segment, each pair supporting a 
long white filament excreted by numerous pores at its base. The fully developed 
female makes a dense sac of waxy matter within which the eggs are laid and the 
shriveled body of the insect remains ; the full-grown male larva makes a similar sac 
within which it undergoes its metamorphoses. 
" During the summer of 1880, I found very common on the Norfolk 
Island pine (Araucaria excelsior), growing in open air in southern Cali- 
fornia, a bark- louse, which is probably the species that was described 
in New Zealand by Mr. Maskell the year previous under the above 
name. 
" When a tree is badly infested with this pest it becomes blackened with 
a black fungus, which I presume is Fumago salicin<(, which accompanies 
coccids on orange and other trees. This is often the first indication of 
the presence of the insect which is observed. But when an infested tree 
is carefully examined, numerous white cocoon-like sacs containing the 
full-grown insects may be seen closely applied to the sides or bases of 
the leaves. Frequently these sacs are so massed at the ends of the 
" l.riococcus araucaria' Maskell. Transactions and Proceedings of the New Zealand 
Institute, vol. xi, p. 218. 
