Tertiary. PALMONTOLOGY OF VICTORIA. [ Mollusca. 
Pirate XLV., Fras. 1 anp 8. 
SPONDYLUS G/EDEROPOIDES (McCoy). 
[Genus SPONDYLUS (L1n.). (Sub-kingd. Mollusca. Class Lamellibranchiata. Order 
Pleuroconcha. Fam. Spondylidz.) 
Gen. Char—Shell irregular, inequivalve, inequilateral ; hinge-line short, straight, forming 
quadrate ears on each side of the beaks ; a flat triangular cardinal area divided longitudinally by 
a median cartilage groove which separates the beak of the large attached valve from the hinge- 
line ; two large cardinal teeth in each valve with pits for opposite teeth, and a triangular 
central cartilage pit connected with groove of cardinal area ; ligament simple, external ; adductor 
impression large, rounded a little on the posterior side of middle; pallial scar, strong, entire ; 
surface rough, spiny. 
Mesozoic to recent warm seas in deep water attached to corals or rocks. ] 
DescripTion.—(See Decade IV., Plate XXXVIII.) 
EXPLANATION OF FIGURES, 
Plate XLV.—Fig. 1, outside view, natural size, of larger valve (bored at one point by car- 
nivorous gasteropod) with more numerous large ridges than usual. Fig. la, view of hinge-tecth 
and cardinal area of same specimen, showing the latter divided in the middle by the cartilage pit. 
Fig. 16, profile outline view of same specimen. Fig. 3, view of upper valve of specimen with 
fewer large ridges than usual, natural size. 
Pirate XLY., Fic. 2. 
SPONDYLUS PSEUDO-RADULA (McCoy). 
Description.—Longitudinally ovate, apical angle about 85° slightly oblique, 
both valves moderately convex, substance very thin; ears rather small, covered with 
radiating very numerous, fine, closely spinulose strie; surface of upper valve with 
about ten to fifteen narrow prominent ridges radiating from the beak, set at irregular 
intervals with long curved, compressed, rather slender spines; between each pair of 
larger ridges are three, five, seven or thirteen very much finer alternate stri, the 
middle one largest, all closely set with fine setaceous spines. The lower valve with 
more numerous spinose ridges (about twenty). Length of large specimens, 3} inches; 
more usual size, about 1} inches; proportional width, ;%%, to 38°; ; length of hinge- 
line, 33%; to 74°;; depth of upper valve, 335, to 34°; depth of lower valve, 3°, to 
yoo; nine fine ridges in a space of 2 lines at 10 lines from beak. 
This thin, delicate species is easily distinguished from the other 
large common species, S. g@deropoides (McCoy), of the same beds 
by the spinulose small ridges between the larger ones. There is 
DEC. Y. elie] c 
