510 PROF. HOWES AND MR. A. M. DAVIES ON THE [DeC. 4, 



functional as an accessory to saltation, receiTing the direct thrust 

 under the weight of the falling body ; and that the structural vari- 

 ations met with throughout the Amphibia are in complete harmony 

 with this view. 



4. That the DiscoglnssidcB are exceptional among the Anura, in 

 the retention for life of the undifferentiated inter-articular syndes- 

 moses ; and that herein is afforded additional proof of their lowly 

 affinities. 



5. That the facts of development herein recorded indicate a 

 possible intercalary origin, from inter-articular syndesmoses, for 

 supernumerary phalanges in general. 



6. That the numerical increase of the phalanges in the Cetacea 

 may have been associated with the loss of the ungues, in a manner 

 similar to that in which elongation, by regular segmentation, of 

 the cartilaginous rays in the paired fins of the Batoidei would appear 

 to have been connected with the disappearance of horny fin-rays. 



7. That, in view ot the facts of structural identity between the 

 modified syndesmoses of certain Anura and the apparatus of the 

 knee-joint of the higher Yertebrata, a reconsideration of the morpho- 

 logical value of the latter is demanded. 



VII. List of Memoirs and Papers referred to. 



1. Baxje, G. — Ueber die Abstammung der amnioten Wirbel- 



thiere. Biol. Centralbl. Bd. vii. pp. 481-493 (1887). 



2. BouLENGER, G. A. — Note on the Classification of the Ranidae. 



P. Z. S. 1888, pp. 204-206. 



3. DixEY, F. A. — On the Ossification of the Terminal Phalanges 



of the Digits. P. R. S. vol. xxxi. pp. 63-71 (1880). 



4. Flower, W. H. — Osteology of the Mamm.alia. Second 



edition. 1876. 



5. Goette, a. — Ueber Entwickl. und Regeneration des Gliedmass- 



enskelets der Molche. Leipzig, 1879. 



6. Henke, W., and Reyher, C. — Studien iiber die Entwickl. 



der Extremitiiten des Mensehen, insbesond. der Geleukflachen. 

 Sitzuiigsb. Wien. Akad. Bd. Ixx. Abth. 3, pp. 217-273 

 (1874). 



7. Howes, G. B., and Ridewood, W. — On the Carpus and 



Tarsus of the Anura. P. Z. S. 1888, pp. 141-182. 



8. Hyrtl, J. — Cryptobranchus Japonicus. Vindobonae, 1865. 



9. Jordan, P. — Die Entwickl. der vorderen Extremitat der anuren 



Batrachier. Inaug. Diss. Leipzig, 1888. 



10. KiJKENTHAL, W. — Ubcr die Hand der Cetaceen. Anat. 

 Anz. Bd. iii. pp. 638-646 (1888). 



11. KL'kenthal, W. — Uber die Hand der Cetaceen. (Zweite 

 Mittheilung.) Ibid. pp. 912-916. 



12. LEBOUCa, H. — La nageoire pectorale des cetaces an point 



de vue phylogenique. Ibid. Bd. ii. pp. 202-208 (1887). 



13. LEBOuca, H. — Uber das Fingerskelett der Pinnipedier und 



der Cetaceen. Ibid. Bd. iii. pp. 530-534 (1888). 



