18 



and Amphibia. The "otic" process of the frog's Suspensorium then 

 corresponds to the articular process of the quadrate of Notidanus, and 

 the upper end of the hyoid forms the hyomandibular in Elasmobranchs 

 and Teleosteans, that is, the frog's Suspensorium is not the same as 

 the Teleostean Suspensorium. This was a complete reversal of his 

 former view. 



The present paper constitutes an endeavour to answer three 

 questions: 1) Which of the above views is the more probable. 

 2) Is the Suspensorium in Teleostei homologous with that in Elasmo- 

 branchii. 3) Are the two latter groups rightly classed together as 

 "hyostylic". An attempt is made to show that 1) the first of the 

 two views of Huxley is the correct one and that the other questions 

 (2 and 3) must be answered in the negative. Considering in the first 

 place the development of the Suspensorium in Teleostei it must be 

 noted that the account given by W. K. Parbier^) is misleading so 

 far as the earliest stages are concerned. More exact descriptions have 

 been given by Stöhr^) and Dohrn^) and for later stages by Huxley 

 in his Croonian lecture. I have made observations on early stages in 

 Gobius and Blennius and on later stages especially in some Siluroids. 

 The process is as follows. The hyomandibular is at first a simple 

 rod of cartilage (Fig. 1). To the anterior surface of its lower portion 



Sty. hy. 



' - ~ Ce. hy. 



M. M. 



Symp. 



Fig. 1. Blenaius, earliest stage to show arrangement of cells. 



1) W. K. Pabkee, Phil. Trans., 1873. 



2) Stöhe, Festschrift Würzburg, 1882. 



3) DoHEN, Mitt. a. d. Zool. St. zu Neapel, Bd. VI, S. 31. 



