238 
According to AYaagon tlio sliell structure of both Martinin and 3Iartiniopsis is 
punctate. In M. sulradiata some of the shelly layers are certainly punctate, others 
equally fibrous. This is shown on one of Mr. De ATia’ specimens, and I have seen a 
similar appearance on New South AVales examples. T should be inclined to regard it as 
punctate-fibrous; some portions of the shell are undoubtedly fibrous, this structure 
having been first noticed by Dana,* whilst the punctate condition was equally elicited 
by De Koninclc. 
It must be distinctly understood that in thus adopting Martiniopsis, as separated 
from Martinin, I have relied solely on AYaagen’s description of the structure of the 
latter. I very much wished to obtain specimens of Martinia glabra, to examine the 
internal structure for myself, but circumstances have prevented this. However, the 
general accuracy of Dr. AY.aagen’s observations emboldens me to place our Australian 
form provisionally in his genus, leaving to others who may have a plenitude of Martinia 
glabra to settle this question finally. 
Types. Martiniopsis inflata,^iiSigci\ (Indian); Martmiopsis subradiata,Movv\9, 
sp. (Australian). 
Martikiopsis subeadiata, &. JB. Sowerly, sp., PL 11, fig. 14. 
Spirifera suhradiatn, G. B. Sowerby, Darwin’s Geol. Obs. Vole. Islands, 1844, p. l.’JO. 
Spirifev subradiatus, Morris, Strzeleoki’s Phys. Descrip. N. S. Wales, &c., 1845, p. 281, 1. 15, f. 5, t. IG, f. 1-4. 
,, glaber, Tiana {non Martin), Geology Wilkes’ U. S. Explor. E.xped., 1840, Vol. x., p. CSS, Atlas, 
t. 1, f. 6. 
„ „ De Koninck [non Martin), Foss. Pal. Nouv.-Galles du Sud, 1877, Pt. 3, p. 227 {exet. syn.), t. 
11, f. 8 and 9, t. 12, f. la-c. 
,, Darwini, De Koninck (non Morris), Ibid., p. 230 (cxd. syn.), t. 10, f. lla-i, t. 11, f. lO-lOa, t. 1C, 
f. 1. 
Spirifera glabra, Etheridge fil., Proe. R. Phys. Soc. Edinb., 1880, v., p. 280. 
Sp. Char. Shell variable in shape and proportions, but usually tran.sversely oval, 
at times becoming very transverse, and both valves much compressed; or short and 
oval, with the valves almost equally convex, iiiuge-line less than the width of the shell, 
with the alar angles always rounded. Area of the ventral valve wide and irregular, but 
in the dorsal valve, narrow, and much longer. Ventral umbo either depressed and 
channelled, or to some extent elevated, and to all intents and purposes entire, usually 
overhanging the area. Sinus wide and plain, bounded by prominent obtuse folds; 
dorsal fold high and undivided, or broad, flattened, and divided by a median depression, 
and often bounded laterally by a groove on each side. Front margin in very convex 
forms much sinuated, but in compressed examples more in one plane. Teeth of the 
ventral valve large and thick ; dental plates strong and long ; cardinal muscular 
impressions long and oval, striated longitudinally and divided median ly by a double 
septum ; ovarian impressions largely developed on the flanks. In the dorsal valve the 
septal plates are very long, frequently reaching half across the valve ; adductor impres- 
sions elongately lingual, separated by a sejjtum. Spiral arms highly developed, and 
nearly filling the interior of the shell. Cardinal process thick and large. The surface 
of the valves is smooth, with the exception of wide concentric laminm of growth, but one 
or more obtuse radiating folds (as many as four) are sometimes present, according 
the variety. On the surface of the cast, numerous indistinct, or half-effaced radiating, 
close ridges are faintly visible both on the flanks and dorsal fold, and in the sinus. Shell 
structure punctate and fibrous. _ ^ 
Obs. Since Dana first referred Spirifera subradiata, Gr. B. Sowerby, to Martin s 
S. glahra, it has been customary to unite with it a number of shells, all more or In®® 
* Geology Wilkes’ U. S. E.xplor. Exped., loc. eii., p. 683. 
