Mr. J. 8. Baly on new Genera and Species of Phytophaga. 439 
species some one or other of these diagnostic marks are fre- 
quently absent. The greatest amount of divergence from the 
typical form occurs in the grooves of the thorax and the striz 
of the elytra: thus in A. bifrons, Erichson’s type (which, ac- 
cording to my views, is an aberrant form of the genus), the basal 
grooves are only represented by faint notches, and the transverse 
suleation is entirely absent ; the striz of the elytra-in the same 
species are also visible only near their extreme lateral border. 
In A. nitida, Waterhouse, the thorax is entirely free from im- 
pressions, whilst the strive of the elytra are only to be seen on 
the hinder half of the disk; again, m A. rugulosa the striz are 
entirely obsolete, the general surface of the elytra being irregu- 
larly punctured and rugulose. Between these extremes and the 
typical species every degree of variation exists ; it will therefore 
be seen that any attempt to divide these insects into genera, 
dependent on the presence or absence of the grooves of the 
thorax or the striz of the elytra, is utterly futile, the arrange- 
ment of [lliger, so useful and complete in reference to European 
genera, breaking down entirely when applied to exotic forms. 
Tabular Arrangement of the Australian Species. 
I. Corpus fulvum. 
A. Elytra distincte punctato-striata ............ variegata, Waterh. 
B. Elytra minus distincte punctato-striata, striis m- 
terdum obsoletis. 
@COLPUS, DLGVIber, OVACUIN 25 6 oa fas aa ie wwe ovata, Waterh. 
b; Corpus anguste Ovatum ...5. 2... 620.5226. attenuata*, Waterh. 
II. Corpus metallicum aut nigrum. 
A. Thorax et elytra levia, non rugulosa. 
a. Antenne breves, subincrassatze .....-.... crassicornis, Waterh. 
B. Antennz longiores, filiformes. 
a. Impressiones basales thoracis obsolete. 
thorax metallieuss. o.4a0+ sc nsane es dsc nitida, Waterh. 
= Dhorax ruto=fulvus) <=... « ; . fulvicollis, n. sp. 
b. Impressiones basales thoracis "semper plus 
minusve distincte. 
+ Sulcus transversus thoracis obsoletus. 
# WGrpus WiSTO-PICeWM, Sec sities pene costye bifrons, Evichs. 
* Corpus metallicum ...... vse femorata, n. sp. 
+t Suleu’s transversus semper plus 1 minusve 
distinctus. 
SUMAN AULVUS es Sd aim sdoleeae eeaene sania cistens bicolor, Waterh. 
* Thorax metallicus. 
t Suleus curvatus faciei medio interruptus .. consuta, Germ. 
tt Suleus curvatus faciei integer. 
§ Corpus elongato-ovatum.............. Chrysis, Oliv. 
§§ Corpus breviter ovatum, crassum. 
|| Abdominis apex fulvus .............. MacLeayi, n. sp. 
\|\| Abdominis apex basi concolor ...... Lownei, n. sp. 
B. Thorax et elytra rugulosa .......-..+..--... rugulosa, n. sp. 
* Mr. Waterhouse has described the sexes of this species under two 
