ON THE CAUDAL AND ANAL FINS OF GOLD-FISHES. 263 



To recapitulate; 



(1) In the paired anal and caudal fins of gold-fishes, the internal 

 bony structures are also paired. 



(2) The Aaew that the hypural bones of Teleostei are homologous 

 with the more anterior pairs of subvertebral appendages 

 receives a certain confirmation by the actual occurrence of 

 paired hypural bones in the gold-fish. 



(3) If the pectoral and ventral fins are to be looked upon as speciali- 

 zations of originally continuous lateral folds in the pre-anal 

 section of the body, the anal and caudal fins are to be regarded 

 as specializations of the same folds in the post-anal section of 

 the body. 



(4) The four pairs of appendages may therefore be considered as 

 homologous structures. 



(5) A certain degree of similarity is still recognizable in the 

 structure and arrangement of parts in these four pairs of ap- 

 pendages in the adult. 



(6) In many gold-fish embryos, a pair of pre-anal and post-anal 

 folds are developed, which may represent the once continuous 

 lateral folds. 



