24 
larf<:er than ((iKstraluKia and less common in the same locality 
amongst pines. It also occurs at the same time, November and 
December. 
( 'icada rinijidata. — In a bit of natural bush near Auckland, New 
Zealand, I have frequently watched the habits of the imago of Cirada 
<d)i;iidat(t, Fabr., the most beautiful Australian Cicadid, expanding 
about three-and-a-half inches. Sometimes I have noted more than a 
dozen settled on one small tree-trunk, imbibing the sap through their 
strong probosces, and all the while making a continuous noise without 
moving their wings in any way. Not nearly so loud is the noise made 
by this species individually, though loud enough collectively, for at my 
house, over half a mile from the woods, at all hours of the day and 
night—except during a thunderstorm—have I heard them. I remember 
once having found many pairs of the Avings of this species, evidently 
snipped off by birds, lying upon the ground at the outskirts of 
a Avood. Their rattle is not so loud individually as is that of < 
australania. 
Cicada Hcrrana, Walk., a small species expanding about an inch 
and a half, abounds eA’eryAvhere in Auckland from .Tanuary to March. 
Walls, trees, bushes and shrubs give forth the Avheezy apology for the 
rattle of C. aastralasia. I haA'e repeatedly tested the fact that if one 
approaches Avithin a feAv feet of this species it instantly ceases its noise, 
and frequently Avill shift — perhaiAS only a feAv inches—from its original 
position. This habit applies to the last-mentioned species also, but it 
is not so noticeable. 
It is evident that to the smaller and less noisy Cicadids their 
“ squeak ” is in no Avay protective, or Avhy the cessation of noise Avhen 
approached ? Does the English C. an<ilica “ squeak ” ? I certainly 
have never heard it. As the poAver of making a noise decreases Avith 
the size of the species, I conclude that if C. aiujlica, Avhich expands 
one-and-a-quarter inches, makes any noise at all it must be A’ery slight; 
inversely, I can imagine Avhat a loud “ rattle’' may be made by some 
of the larger Cicadides of the Tropics, such as Dundahia iiiijicrataria, an 
East Indian species, Avhich expands eight inches. In Australia and 
Ncav Zealand, late in the afternoon, until long after dark, is the time 
Avhen they are noisiest. 
Note on the structure of the uaiaoo. —Antenna^ short, CA-en 
jointed ; eyes protruding at each side of head ; on dorsal surface of the 
head, betAA'een the eyes, are three ocelli, equidistant, as if set at the 
corners of a triangle ; these are quite as brilliant after death as before, 
I doubt, therefore, Avhetber they serve any function other than ornamen¬ 
tation. The ocelli of C.aastralania are like minute rubies set in a patch 
of black colour. The colour of the ocelli varies someAvhat Avith different 
individuals and also Avith the different species. Wing connection. — A 
small turned-up edge of tlie costa of the hind Avings catches the 
turned-doAvn edge of the loAver marginal nervure of the fore-Avings 
Avhen expanded. At rest the fore-Avings are considerably longer than 
the abdomen. 
Organ of hound in C. Australasia. — Tlie first abdominal segment 
has tAvo concave dorsal plates, a depression or cavity in the thoracic- 
abdominal incision, Avitb a small dorsal orifice and a large A'cntral 
orifice, connected by a narroAV slit Avhero tbe dorsal plates do not quite 
touch the thorax ; the cavities on either side have a membranous 
