Additional Notes on South African Phyllopoda. 25 



apposed marginal area only indicating a very long growing 

 period beyond the normal one, caused in all probability by 

 some favourable physical and biological conditions existing 

 in the places where the specimens occurred. In these 

 specimens also, the shell was covered by a thick crust of 

 argillaceous matter, which could only be removed with great 

 difficulty, in order to see the sculpture of the shell. The 

 lines of growth here, too, were very numerous and densely 

 crowded together in the outer part of the valves, the marginal 

 area being regularly and densely striolate. Figs. 8 and 9 

 on the accompanying plate represent the shell of a female 

 specimen, seen laterally and dorsally, and fig. 10 the shell of 

 a male specimen seen from the right side. The female shell 

 measures 8.9o mm. in length with a height of 4.9o mm., the 

 male 10.70 mm. in length with a height of 5.60 mm. The struc- 

 ture of the enclosed animal agrees very closely with that in 

 the specimens from Green Point Common, as shown by the 

 detail-figures 11, 12, 13 here given, all from a male specimen. 

 Another specimen of a somewhat more anomalous aspect 

 is represented in fig. 4. It is an apparently fully grown male, 

 which was taken by Mr. Sculley in the Bushman! and,^ 

 accordingly in a rather remote region of South Africa. On 

 a comparison of this specimen with the male represented in 

 fig. 2, the disproportion between the shell and the enclosed 

 animal is rather striking, a much greater part of the body 

 being exposed behind in that specimen. It is, indeed, rather 

 difficult to imagine how, in the present specimen, the whole 

 body could have admitted of being received within the hollow 

 of the shell, though this must undoubtedly have been done 

 in the living animal. The shell itself is rather thin and 

 pellucid, being 8.7o mm. long, with a height of 5 mm., and 

 is accordingly comparatively shorter in proportion to the 



