206 
HORN EXPEDITION—MOLLUSCA. 
This species comes near P. zvallabyensis, Smith, but according to that author 
differs in its apertural armature. 
Pupa mooreana, E. A. Smith. (Plate XIX., Fig. 20.) 
Reference—Proc. IVIalac. Soc., June, 1894, 97, t. 7, f. 25. 
A shell which I refer to this species was collected in considerable numbers in 
Central Australia. The majority of the specimens have the denticulation of the 
aperture as figured and described by Smith, which consists of a strong plait in the 
middle line of the body-whorl, one on the columella, and two palatal, the four 
being appro-ximately ecpiidistant, whilst a denticle is situated at the insertion of 
the outer lip. Some variation in this ari-angement is supplied by my specimens, 
the parietal and columellar plaits are relatively very large, and occasionally a 
denticle is interposed, as also another between the two palatal plaits, whilst the 
tubercle at the insertion of the labrum is often absent. 
Localities. —Tempe Downs, Reedy Creek, Palm Creek, Stuart’s Pass, Painta 
Spring, and Alice Springs. 
Family Succineid^. 
Genus Succinba. 
The test of the Australian species of this genus, except A. strigiilata and 
A legrandi, which have not been under observation, possesses on the outer 
surface, between the growth-folds, a micro-ornament consisting of two sets of 
obliiiue striie which, intersecting, produce a rhombic reticulation. In A scalarina, 
A interioris, A eucalypti and A ta/narensis, this kind of ornamentation is 
bold; in A nortoni and A macgilUvrayi it becomes somewhat granulose ; in 
A strigata, A australis, and A aperta the ornament is feebly developed, and 
in the last approximates to granulose. The only exotic species examined are the 
European A putris and A elegans, in which the sculpturing is absent, and 
the Central American A recisa, in which the ornamentation is like that of the 
Australian A macgilUvrayi. 
The diversity of this character, as exhibited in the above-named species, 
renders possible its employment as an aid to the discrimination of .species. It is 
signiticant that A interioris and A scalarina, and A australis and A strigata 
should have similar ornamentation, well-developed in the former pair and feebly so 
in the latter, as there is no doubt that the species of each couple are closely 
related and perhaps conspecific. 
