[Pkoc. Koy. Soc. Victoria, 25 (N.8.), Pr. 1., IDi:.'., 



Art. XIII. — On Some New Species of Victorian Marine 



MoUit.sca. 



Bv J. H. GATLIFF and C. J. GABRIEL. 



(With Platf IX.). 

 [Read nth July, 1912.J 



This ])ai)t'r contains the description of three new species of bivalve 

 shells. 



Montacuta dromanaensis, sp. nnv. (Pi. IX., Figs. 1-4) 



Shell minute, sordid white, very inequilateral, tiuely ornamented 

 with concentric, irre;jrularly undulatin<i- striae : the re-sel are dis- 

 tincth^ capped by what appears to l)e the early stage of growth. 

 Equivalve. 



JJiiiH'iis/oiix of Type. — Anterior-posterior diameter l.G, dorso- 

 ventral diameter 1.2 mm. 



Lorardy. — Type from Dromana San llemo (T. Worcester). 

 Dredged between Phillip and French Islands, AVestern Port. 



06s. — Tliis species can be readily separated from our other forms 

 by its concentric sculpture. Type in Mr. Gatlifi"s collection. 



Condylocardia chapmani, sp. no\. (PI. IX., Figs. .5-8). 



Shell minute, white, shining, transj)arent, hinge being d'scernible 

 from the outside through the shell. Very inequilateral. Ovate, in- 

 flated. Liuiule slightly discernible. There are three growth lines 

 visible. Equivalve. 



Dnntn^Knix of Z'^/yy^. —Anterior-posterior diameter 1.4, dorso-ven- 

 tral diameter, 1 mm. 



Locality. — Type dredged oft" Portsea, Port Phillip: Ocean Beach, 

 Point Nepean ; Torquay. 



Ohs. — A very small, smooth, simple form. Type in Mr. Gatlitl's 

 collection. 



Modiolaria rhyllensis, sp nov. (Pi. IX., Figs. »), 10). 



Shell small, equivalve. subo])lique, profoundly convex, semi- 

 transparent, horny colour. Valves thin, fragile. Umboes prominent, 

 with the beaks projecting and slightly incurved to the anterior ; 

 the umbonal swelling giving rise to a somewhat sharp slope to the 

 anterior, but a more gradual dip, and with a manifest concavity to 

 the posterior. Ttie anterior border is straight and decidedly produced 

 posteriorly. 



As regards sculpture, the shell is adorned with closely-set, radiat- 

 ing ribs, whose surfaces are obtuse and slightly raised from their 



