22 
and compressed with a keeled belly and scattered spines. In /ent#- 
cularis we have a compressed form with a keeled back and belly and 
no spines. The compressed Ostracions with scattered spines have been 
characterized by Mr. Gray as a subgeneric group, under the name 
of Aracana, and several Van Diemen’s Land species were lately de- 
scribed to the Society by the author of the present paper. The Aracana 
Reevesii (Gray) from China differs from the Van Diemen’s Land 
species in having the back slightly keeled, and thus forms a transi- 
tion to the form of /enticularis, in which the sides are convex, the: 
back and belly acute, and the profile elliptical. Lenticularis, though 
unarmed, exhibits an analogy to the armed Aracane, in the umbones 
of the reticulated surface being largest where the spines would be 
situated, did they exist. The species is Australian, and the author 
expresses his obligations to Dr. Andrew Smith, of Fort Pitt, for the 
loan of two specimens of different ages. 
3. ANGUILLA AUSTRALIS. Van Diemen’s Land Eel. 
ANGUILLA AUSTRALIS, mawilld inferiore longiore, pinnd dorsi supra 
anum incipienti, rictu magno. 
This is a Port Arthur freshwater species, for which the author 
expresses himself indebted to Mr. Lempriére. It differs from the 
common freshwater eels of Europe in the more posterior origin of 
the dorsal, as well as in the more anterior position of the vent. The 
pectorals are lanceolate, the vertical fins are but moderately high, 
and the gape extends to the posterior margin of the orbit. 
4. Narcrnz Tasmantensis, dorso dipterygio, corpore late obovato ; 
valvuld nasali obtuse trilobatd integerrimd ; pinnd ventrali disco 
pectorali approvimatd. g 
‘The author having but recently had an opportunity of consulting 
Henle’s Monograph of the genus Narcine, takes this opportunity of 
supplying a specific character of the Van Diemen’s Land species, 
which was formerly described to the Society (Zool. Proceed. for 
March 1840, p. 29), but which could not be distinctively character- 
ized from his want of knowledge of the other species. 
A paper by W. J. Broderip, Esq., in which the author proceeds 
with his descriptions of Mr. Cuming’s shells, was next read. 
Heurx cryprica. Hel. testd tumidd, subumbilicatd, subglobosd, 
anfractibus 3 subcorrugatis (ultimo long? maximo, obscure fascia- 
to), lineis incrementi creberrime obliqué substriatis, purpureo- 
brunned, epidermide sordid? brunned ; apertura subelongato-auri- 
culiformi, intus subargenteo-carulescente, subiridescente ; labit 
limbo rubro-brunneo, haud patulo, reflexo. 
Long. 1£; lat. 22 poll. 
Hab. ad Catbalonga Insule Samar sub foliis desiccatis. 
Mr. Cuming found this Heliz hidden under the decayed leaves of 
trees. The inside of the mouth has that silvery iridescence which 
may be observed in the tendon of a muscle in some of the mammife- 
rous animals, and through it may be seen the purple-brown colour 
of the shell, which thus puts on a subcerulescent appearance. 
