[CEYLON PEARL OYSTER FISHERIES 1903 SUPPLEMENTARY REPORTS, No. IV.] 



REPORT 



ON THE 



POLYPLACOPHORA 



COLLECTED BY 



Professor HERDMAN, at CEYLON, in 1902. 



BY 

 E. E. SYKES, B.A., F.L.S. 



[With ONE PLATE.] 



The large proportion of species described as new in the following pages is not so 

 surprising as it might appear, since we know but little of the fauna of Ceylon, so far 

 as the Chitons are concerned. 



The collection includes nine species. Of these, three are identified (one doubtfully) 

 with known forms ; five are described as new ; and, in one case, that of a single 

 specimen of an Ischnochiton, I have thought it wiser to give no specific name. 



Callochiton sublsevis, n. sp. Plate I., fig. 3. 



Shell in shape, sculpture and girdle pattern similar to C. Icevis (Mont.). Colour a 

 uniform dark red, the interior of the valves being the same colour. The valves 

 slightly concave in front of the line dividing the lateral and central areas. Valve 

 slits: anterior 14, median 1, posterior 15. 



Length, when alive, about 12 millims. 



Hah. : Navakaddua Paar, 7 fathoms, on Coral (one specimen). 



The only salient features that I can trace to sever this form from the European 

 C. Icevis are the median valves having only one slit, the dark red colour inside the 

 valves, and the slight concavity before the line dividing the lateral and central 

 areas. 



There is, in the British Museum, a single specimen from the Philippines, bearing 

 the manuscript name of sublcevis, Carpenter, which probably belongs to the present 

 species. 



2 A 



