Vol. 68.] IN THE ' PEEMIAN ' EOCKS OF HAMSTBAD. 665 



the centre of the footprint, but a semicircle of claw-impressions 

 curved and slightly pointed. The toe-tips or claw-markings are 

 respectively -3, -5, -6, -8, and -3 cm. long. The breadth is 1*3 cm. ; 

 the length is not determinable. Track-measurement 1 = 1 cm.; 

 track-measurement 11=2 cms. ; width of track = 2 cms. 



The footprints classed as H2 (fig. 15, below) are considered to have 

 been made by the animals of the same species as those of Ichnium 

 pacJiydactylum (fig. 16), which has been recorded by Prof. Pabst from 

 the Middle Rothliegende of Thuringia and from the Eothliegende 

 of Silesia, Bohemia, and Moravia. IS'o other similar footprints from 

 the Permian areas or from Carboniferous rocks are known to me. 



Pig. 15. — B.,^ from Hamstead Pig. 16. — Ichnium pachy- 



(half of the natural size). dactylum from Friedrich- 



roda (half the natural size). 



The description of the Hamstead form Type H2 (PP- 663-64) 

 will apply equally well to Pabst's /. ijachy dactylum. As in the 

 Hamstead specimens of H^, the toes of the British specimens of H^ 

 have left shorter impressions than those of their representatives 

 from the German Eothliegende. The first toe on the foot is not 

 shown on the fore foot of any Hamstead specimen, while it is often 

 absent from the hind-foot impression. Comparative measurements 

 of the Hamstead and Eothliegende specimens are tabulated on 

 p. 664. Track-measurements I and II appear only very doubtfully 

 on the Hamstead specimens. If my reading of them be correct, 

 they are larger than the similar measurements in the German 

 /. jpachy dactylum . 



Sub -Type H2a. Ichnium pachydactylum (minus) Pabst. 



These appear to be the footprints of a young form of H2, and 

 may be, therefore, compared with I . jpachy dactylum {minus). On the 



