EXPLANATION OF PLATE XX. 



Vertebra) of Fijthonomorplia, onc-lialf natural size : species, Platccarpus icterictts aud Platccarjms cori/pliaeus 

 Fig. 1. riatccarpiis ictericiis, median dorsal vertebra : a, from behind ; h, from below ; c, from front. 

 Figs. 2-3. Platccarpus ictericus, Inmb.ar vertebra : a, from behind ; b, from below. These vertebrie were 



found lying on their sides, and the form of the articular surfaces is slightly altered by 



pressure. 

 Fig. 3. Posterior lumbar vertebra : a, from before ; fc, from below; c, from behind. 



4. Platccarpus corypha'iis, axis and third vertebra: a, from the side; 6, from below; o, from behind. 



5. Three cervical and two dorsal vertebra) : i,e, (?, and c, views from side, below, behind, and above, 



respectively ; g, h, i, k, and I, similar views of another ; m, n, side and front views of an ante- 

 rior dorsal. 



G. A posterior cervical from behind. 



7. Posterior dorsal vertebra : a, from below ; J>, from above. 



