Thilo’s memoir on »Die Umbildungen an den Gliedmaßen der Fische«. 187 
Dactylopterus volitans L. The coalesced Hyomandibulare and 
Preeoperculum!. (My book, pag. 75—78.) 
With regard to the diarthrosis there is this difference between 
the interpretation of Dr. Tumo and mine, that according to his 
opinion the »Scheibe« (»A« in his Fig. 41) is part of the diarthrosis 
but in my opinion a »Hemmfortsatz«, as well as the anterior pro- 
cess, which he has designated by this name. (When Dr. Taio, 
pag. 348, says that I have called this one [alone] a »processus vo- 
calis«, then this time it is not my fault: for nowhere in my book 
have I used this? term, and in my Figg. 37 and 38 I had indicated 
the »Scheibe A« of Tito as well as his »Hemmfortsatz« by the 
letter 0, which in all my figures has been employed to indicate 
either the scouring faces or the processus on which they are placed.) 
That »die Hebemuskeln des Stachels entspringen vom Para- 
sphenoid und Orbitosphenoid« is an impossibility. According to my 
investigations they spring partly from the Infraorbitalia partly from 
the outer side of the skull. 
Though I have tried to speak briefly, I believe that the diffe- 
rence between the view of Dr. Taro and mine is rather displayed 
with tolerable clearness. And I therefore venture to hope that I 
shall not be obliged to return to this subject in future. 
But in case Dr. Tuo should give a reply to these remarks, 
I may perhaps ask him to answer the following questions occasioned 
by his memoir: 
1. Dr. Tuıto states (pag. 334) that in Cobitis, the Siluroide of 
the Nile and the species of Mormyrus »könnte die Athmung fol- 
gendermaßen zu Stande kommen: 1) Der Fisch füllt Speiseröhre und 
! Dr. THILO says (pag. 346) that these bones are also coalesced with the 
Operculum, Suboperculum and Interoperculum. I regret that he does not say how 
he has then interpreted the three small ossicles which I had represented under 
these names on my Figg. 39—42. In my opinion they must be these bones as 
they (at all events Operculum and Suboperculum) are situated in the same 
place as the bones which in other fishes are designated by these names. — 
CuviER et VALENCIENNES too mention (op cit. T. IV, pag. 123) the Operculum, 
whose special muscles are given in my figures. 
2 In some places I had in the »explicatio figurarum« used the term »pro- 
cessus affigens s. sonivius« for the processes J. But in Dactylopterus I had 
not even used this term. 
