399 



Median valves. — The dorsal area broadly wedge-shaped, 

 highly arched, longitudinally convex, beaked, pinnatifid. The 

 markings and sculpture are a little difficult of definition, there 

 is present a series of whitish spots arranged longitudinally on a 

 dark-pink ground, the wavy longitudinal and transverse striae 

 together with the colour markings give a granulose appearance 

 to the whole of this area, which may be described as looking 

 like strings of very small granules separated by dark-pink 

 lines. The pleural and lateral areas are inseparable, are tra- 

 versed by widely spaced, rather coarse, raised but flat pustules, 

 under microscope they look like whitish, flat topped flagstones 

 laid on the crown of raised portions of the tegmentum. Inside 

 pink, insertion plates pink, slit one. 



Girdle. — Spongy, a few scattered short spicules and an 

 incipient fringe. Hair tufts well defined, spicules short. 



Measurement. — The type (dry) measures 5 mm. x 2| 

 mm., being a little curved, probably 6 mm. would be nearer 

 correct. Mr. Gatliff's shell 6 mm. x 3 mm. and Mr. Gabriel's 

 shell 8 mm. x 4 mm. 



The type remains for the present in my collection but I 

 shall hope ultimately to place it in the South Australian 

 Museum. 



Hab. — I collected the type myself at Port Lincoln, South 

 Australia, and sent two others, collected at the same place and 

 time, to Mr. Iredaie as being the same; but until these are 

 returned to me and I can examine them under a microscope I 

 cannot absolutely determine their identity. Messrs. Gatliff 

 and Gabriel have both loaned me single specimens obtained off 

 Point Cook, Port Phillip, Victoria, in 8 fathoms. 



Remarks. — I am indebted to the two gentlemen above 

 named for the oppportunity of examining their specimens ; 

 they exhibit a few minor differences. Neither show the pink 

 colouration which is such a marked feature in the type ; it is 

 possible that their specimens may at one time have been in 

 spirit which would remove the colour. Mr. Gabriel's shell, 

 which is the largest of the trio, has a distinctly rugose dorsal 

 area, becoming granulose toward the beak ; the pinnatifid 

 character of this area is more distinct, and there are evidences 

 of very minute scales on the girdle and of a girdle fringe. 



This interesting little Acanthochiton has been in their 

 collection for some years, but was wrongly identified by them 

 as Sykes' shell A. pilsbryi, a species dealt with in the earlier 

 portion of this paper. 



I am naming this shell after Mr. Gatliff, who with his 

 colleagues has done much good work on the Victorian fauna. 



