Manchester Memoirs, Vol. Iv. ( 1 9 1 1 ), No. IT. 3 



There are, however, certain slight differences of the 

 limbs which suggest that the species is a good one. It is 



Fii;. 2. Eight fore paddle of Microckidus 

 hoiiiacospoiutyiiis, dorsal aspect, x \. 

 L. 7077. Manchester Museum. 



very probable that the specimen at York, which is one of 

 Owen's co-types oi P. hoinalospondylns x&-d\\y belongs to 

 M. macroptenis and not to the species to which it was 

 originally referred. In this way the differences between 



