424 



MR. G. A. BOULENGER ON A NEW 



[Mar. 15, 



anterior portion of which is broken away), the two intermediate 

 teeth, with between them the diminntive tooth which had up to 

 now escaped the describers of " Sorex picsillus," and the anterior 

 true molar. 



The diminutive tooth in question is slightly larger than the 

 additional tooth occupying the same position in the recent 

 Myosorex varius. So long as more fossil forms are unknown, the 

 homologies of these intermediate teeth will remain doubtful ; 

 the diminutive one is presumably the homologue of the tooth 

 which M. F. Woodward found as a vanishing structure in an 

 embryo of Sorex (sp. ?), and which he considered to be the third 

 lower permanent incisor *. 



Mr. G. A. Boulenger, F.R.S., exhibited a remarkable Ichthyo- 

 saurian right anterior paddle (text-fig. 83) from the neighbourhood 

 of Bath, which he had received from Mr. H. E. Lansdown, of 

 Bath. The locality and horizon of the specimen, which had been 

 in the possession of the late Miss Mary Ashley, were unknown. 



Text-fie-. 



mm 



o<3- 



A 





c 



Right anterior limb of A. Mixosmirus cornalkmus (after Repossi) ; J?. Ichthyo- 

 saurus communis (after Lydekker) ; C. Ichthyosaurus e.vtremus. 



In having three facets to the distal extremity, the humerus of 

 this specimen, had it been found isolated, would have suggested 

 OphthcdDiosaurus (from which Baptanodon can hardly be separated 

 on the evidence available at present) ; but, as shown by Seeley, 

 the three facets of the Ophthahnosaxirus hvimerus are for articula- 

 tion with the radius, the ulna, and an ulnar sesamoid bone 



* Proc. Zool. Soc. London, 1896, p. 569. 



