Mr. C. Hedley on the Range o/'Placostylus. 435 



apex of the body, tlie venation lonjifituclinal. Abrlomen with 

 the lateral mar^^ins produced and convex. Rostrum ju3t 

 passing the anterior coxaj. iMcsosternum wide ; a transverse 

 elevation between the intermediate and posterior coxw, which 

 are situate close together. Abdomen beneath very flat and 

 depressed. Legs tinely setose. 



This is the first Australian genus of this division of the 

 Tessaratominaj with which I am acquainted. 



Garceus Jidelisy sp. n. 



Pale uniform ochraceous. Antenn?e with the first and 

 third joints subequal in length, second joint longest. Pro- 

 notum and scutellum with an obscure central longitudinal 

 earination ; pronotum with a distinct fovea on each si<le of 

 the anterior area, the lateral margins laminately ampliated 

 and sligjitly recurved ; the whole disk obscurely transversely 

 wrinkled. Scutellum and corium thickly, obscurely, and 

 finely punctate. 



Long. IG millim. ; lat. pronot. angl. 8 millim. ; max. lat. 

 abd. 10 miilim. 



Hab. Australia j Peak Downs, in Queensland. 



LXX. — The Range o/Placostylus : a Sfudg in Ancient 

 Geographg. By C. Hedley, F.L.S.* 



The genus Placostylus appears a more fruitful subject of study 

 than any other molluscan genus inhabiting the same area. 

 Their large and handsome shells have attracted the attention 

 of the most superficial and unscientific collectors ; as a result 

 an extensive series of them have been brought to our know- 

 ledge from remote localities. Close and attentive scrutiny 

 would scarcely justify an observer in declaring that a parti- 

 cular minute shell did not itdiabit any given island, whereas 

 a casual survey would decide whether a con3j)icuou3 shell 

 like Placostglus did or did not compose a portion of that 

 island's fauna. A larger mass of evidence, both negative and 

 positive, is therefore at our disposal in dealing with Placo- 

 stylus than awaits us in studying smaller species. 



The genus ranges from Faro Island, Solomons (P./ounaki), 

 in the north, to Whangarei, New Zealand (P. bovinus), in 



* From the * Proceedings of the Linnean Society of New South Wales,' 

 August yi, 1893. Communicated by the Author. 



32* 



