356 BAUR. [Vol. IV. 



ogische Bedeutung der sogenannten Cartilage ypsiloides oder 

 epipubis halte ich mit meinem Urtheil vorderhand noch 

 zuriick." 



In his latest paper on the subject (Anat. Anz., 4. Jan., 1890), 

 the epipubis is compared with the episternum: "Wie dem Schul- 

 tergiirtel vorn das Episternum, so sitzt dem Beckengiirtel der 

 Urodelen und weniger Anuren vorn die Cartilago epipubis auf. 

 Sternum, Episternum und Cartilago epipubis der Amphibien 

 sind homologe Bildungen, vorauf bereits Gotte hingewiesen hat." 



Wiedersheim is inclined — to conclude from his text-books — 

 to consider these elements as the same as the epigastroid. I 

 do not believe that this is the case. The epigastroid is always, 

 also, in Necturus,^ in which I could study its evolution on ma- 

 terial kindly given me by Professor C. O. Whitman, the anterior 

 portion of the gastroid cartilage, from which it is not developed 

 independently. I believe that the ypsiloid cartilages are of 

 secondary origin, developing independently from the gastroid 

 cartilage. The long epigastroid of the Chelyiidae is homologue 

 to the short epigastroid in Testudinidae ; homologue to the 

 anterior portion of the gastroid cartilage in Necturus ; homo- 

 logue to that portion of the gastroid cartilage in Salamanders 

 and Dactyletra, to which the ypsiloid cartilages are connected. 

 I consider these cartilages as a later acquisition ; they may 

 develop in any group, — Batrachia, Pterosauria, Monotremata, 

 Marsupialia. The question now is, how to name these elements. 

 The name epipubis is not good, having been used, also, for an 

 element which is not homologue. Ypsiloid cartilages and mar- 

 supial bones are also inappropriate names. I think it best to 

 introduce the name cartilago pyramidalis, to express the relation 

 of these elements to the musculus pyramidalis. 



We have to return now to the Crocodilia and Pterosauria. 

 The peculiar condition of the pelvis of the Crocodilia exists 

 already in the Lias. This structure, therefore, is a very old 

 one, and I have some doubt whether embryology will give us 

 any help in this question. Perhaps it is possible to get some 

 light by examining the pelvis of the Pterosauria. I was always 

 inclined to consider the ischium of Crocodilia and Pterosauria 

 as this element alone, and the anterior bones as the true pubes ; 



^ I may state here that in Necturus a distinct but very small sternum is present. I 

 found it in all specimens examined. 



